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h8er b8

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d4 j00z!!!! Don't give the antenna j00z your money just to Dx!

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the chad ham

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the chad scanner

>>2960058
Is this as hard to make as it looks? I want to make a discrete aerial for contacting other survival communities in the event of ww3

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>>2960058
Thank god they put this secret information in here, otherwise I wouldn't be able to build such a thing. Don't tell anyone :-)

>>2960020
>I can see using a child's bow and arrow
He used a professional kit. He used an arrow that had instead of a sharp tip, some kind of rubber bulb-like cover on it so it wouldn't get stuck in the tree. Fishing line was attached to the end of the arrow where the fins are. The trick was getting just enough height to reach and arc over the branch selected. It took a couple of tries. We were stringing a 40/80/160m trap dipole up ~90 ft in Douglas Fir trees for Field Day.

>>2960107
>Collins 75A1
>box of 'Special K' cereal
Should be a good night dxing. :^)

the other day i learned how AM towers can actually kill you. neat.

question:
does the resistance of your antenna coax have to be balanced with the resistance of the antenna?

>>2960198
No, the portable version is linked at the top of the thread.

>>2960203
Don't underestimate the idiots.

>>2960229
All high power towers are dangerous. Imagine touching a live wire with 500kw going through it.

>>2960106
No point when police are all using encrypted modes now

>>2960198
Not at all. I made my portable j-pole out of tv twin leadthat was just being thrown away and a banana clip.

>survival communities
There's a lot that goes into that, anon. How far away? Are you all coordinating frequencies and times? Do you all have towers you can reach and have repeaters available if shtf? How much power do you have available?

The best is use HF. J-poles don't make any sense in HF. You are better going with verticals and standard dipoles. If you need multiband: fan dipoles, trap dipoles, end fed half waves, and off center fed dipoles. You can be an idiot and use a random wire with a tuner, but you lose quite a bit of power out and they're noisy.

>>2960058
>>2960203
Why would anyone give formulas for feet instead of inches? Decimal feet are annoying.

>>2960229
With AC, impedance is used instead of resistance. It takes into account inductance and capacitance (reactance), which appear resistive and conductive at frequency.

Your coax and antenna should both be matched to your radio.

>>2960239
not where I live. only some are encrypted.

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let me guess, you need more

>>2960058
This looks like it was made cad drafting software from 1995.

>>2960361
>amount of adapters
Kek

We can have 1/2 and 1/4 wave antennas, but why doesn't this series continue? 1/8, 1/16, etc.

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Has anyone taken the FCC T1 (15wpm) and T2 (20wpm) exams? I'm not finding much on what the different COLEMS send or how to prepare.

>>2960480
5/8 enters the chat

>>2960535
What's so special about the ratio 5/8?
Why does that come up a lot, but other odd fractions don't?

>>2960553
https://practicalantennas.com/designs/verticals/5eights/

>>2960570
Oh, okay.
Cheers m8.

>>2960247
Cheers anon. These are good points. I kinda assumed the antenna would "just werk" and everyone would start to find each other by scanning around the spectrum after a few days. Didn't assume it would be HD audio quality more like 1970s cop radio quality. I guess I've watched too much TV. I feel like every household should have some sort of radio handset for when ww3 eventually breaks out and all the networks go down for one reason or another

In the time I just spent trying and failing to comprehend NEC, I could have built an antenna and run my experiments with a VNA

>>2960581
I guess I'm just a caveman tier dude about it.
I'm not trying to talk to Mars here. I'm fine with the 'just try it, and if that doesn't work, trim it and try again' strategy.
Is it actually transmitting? I dunno, poke that bitch and key up, if it hurts, it's going.

>>2960573
You could just scan. Sdrs are great for that. You can visually see the frequencies are being transmitted on. It's hiw I found a few ham repeaters that are not publicly listed. Just looking at the spectrum on the SDR is a part of intel gathering. It is a major part of what's happening in Ukraine atm.

I just read a series recently which communities were trying to link with each other. What were they using? CB only. Now, you can do skip (long distance) with CB since it is in HF, but that depends on many circumstances. It's relevent now due to the current solar cycle we are in. However, the way the books had it set-up was unrealistic and you could tell the author just got an extremely quick crash course on radios.

Though, it was just a story. My radio autism just had me going during that time.

>>2960583
It would be way easier to simulate it if simulating it were easy though. Real wire costs money and you can't un-cut it.

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>>2960056
Well I wanted to get in on HF for cheap cheap and had good experience with Chinese tech in the past so I bought into the (tru)SDX and usdx+ meme.
>blew finals on trusdx a couple of times
>managed one ft8 contact on 17m
>blew finals chinese black box usdx+ a good couple of times (6-7) too
>managed 150+ ft8 contacts on 20m
>pads on the PCB where to solder the finals to have finally started to give out
>bought an antenna tuner maybe it would prevent it somehow
>nope
Yes I'm a massive retard for other stuff but I would check SWR for my antenna and it would work pretty well when I managed to tune it to 14.050 which is pretty damn close to 14.074. And I mean in order for it to transmit the SWR has to be literally 1.09 or 1.05. Anything like 1.2 and poof go the finals. And the best part is I didn't even need to turn on transmit in wsjtx. When you use vox mode, it sends out these transmit pulses as soon as you connect the mic input so you can blow them without ever turning transmit on.

>>2960634
I blew out a few QDXs and a trusdx. Swr was fine. It's why I don't waste myoney on those gimmick mini radios any longer. If I wasn't at home at the time, the one QDX would have caught on fire.

>>2960634
>pads on the PCB where to solder the finals to have finally started to give out
wtf ? There should be not a lot of power there, is it arcing ?

>>2960590
True, but I already have a bunch of scrap wire, and instead of cutting it I can just fold a loop at the end to adjust the length if I want to be that miserly about it.
I'm not against simulation, but I've been having trouble getting the damn software to work, and I don't want to deal with more pain in the ass linux shit.

>>2960634
If it’s an issue, those meme radios should have a thermistor on their final transistors to throttle back when they’re getting too hot. Plus TVS diodes for overvoltage conditions if they don’t already. Or a ZIF socket for the transistors.

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putting a 10w repeater on my roof for giggles

gonna make a little field manpack baofeng repeater deal for when im inna woods

also got two mp31's for an even shittier simplex repeater deal

mp31 is hyper based I wish they came as a 4 pack

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>>2960361
5rx master race rise up

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>>2960823
previous statement redacted

mp31s are cool but not based. they are locked to narrowband and cannot transmit or receive wideband and that is gay

I will proabably get x2 8 watt uv5rs then

why do I need a loicense to transmit on a hand held on the higher watt channels. If I am driving around and transmitten can they still find me, or tell who I am, does the radio transmit a special unique code super secret that is traced back to that particular radio?

Can I use the lower power channel and giant antena to transmit farther without muh loicence?

>>2960850
just use CB then. Why would you want to transmit on random frequencies without a license anyway? There wouldn't be anyone to talk to

Turns out my cheap HDMI cable with the DVI adapter is radiating noise at a local 2m repeater frequency, explains why I hear nothing but buzzing when I have my radio indoors. Clipping a pair of ferrites on it did nothing, neither did swapping to a better HDMI cable, but swapping to a cable with integrated DVI adapter stops me from picking up the noise sufficiently well that I shouldn’t have a problem with it. I guess the DVI-D to HDMI adapter is really poorly shielded or something.

It’s a 1200x1024 DVI monitor but I can’t smudge the numbers around to get 434.050MHz, harmonic or otherwise. Even with the 10/8 bit encoding, assuming 60fps. Maybe there’s some sort of legacy TV stuff like blanking intervals going on. SDR couldn’t see it, but it was plugged into the same computer.

>>2960861
congrats on finding the source of the noise, I had the problem with VGA

>>2960850
>can they still find me, or tell who I am,
no and no

>>2960850
>does the radio transmit a special unique code super secret that is traced back to that particular radio?
Not intentionally.

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>>2960850
you don't really. the fcc doesn't really give a shit no matter how many times some autist reports you. in order to actually get a strongly worded letter from the fcc you gotta be making disruptive interference for a long long time, or you are interfering with emergency services radios. If you transmit on a police or hospital frequency or start running a pirate radio they will be more pissed at you.

And to the
>can they still find me
>or tell who I am

yes and maybe

even if you're driving, someone else in a car can geo locate you and track you down on the highway, see you're face and car and license plate bumper stickers etc. They might be able to deduce who you are from that, if not, they can forward that info to the fcc. not that they will really do anything

If you transmit on a frequency you don't have a callsign for, what realistically will happen is someone's going to tell you that you need a license to transmit on that frequency or channel. then they'll stop talking to you. they'll get off the air or jump frequency and start talking somewhere else

a gmrs license costs 35 bucks and takes like 5 minutes. theres no tests. then you can do whatever the fuck you want on gmrs and have a blast. or just buy a CB. an old rig like a soundtracker on fb marketplace costs $5. then get a nice antenna, coax, swr meter

Fellas, is EZNEC decently accurate modeling software?
It seems to run well, but I wouldn't mind hearing some opinions on it's usefulness before I commit to grinding the manual.

>>2960912
>in order to actually get a strongly worded letter from the fcc you gotta be making disruptive interference for a long long time,
oh like this guy?
https://youtu.be/KGTY8Ofpu4M

>>2960989
Kek, the gmrs guys in my area are a bunch of good 'ol boys, to put it mildly, but they're the smart kind.
A while back, some jogger activist type tried to troll them, but turns out they're quite adept as fox-hunters, and they pinpointed his ass in like 15 minutes.
Upon discussing his location, he gave up.
Not that they'd have actually done anything beyond that, but from his sudden silence he must have thought the klan was after his ass.
Weird episode to listen to.
The only downside was I had to refuckulate my rx ant to catch the repeater signal since they turned it down for a few days.

>>2960993
this guy has a license. everyone knows where he lives. the FCC was notified many times and he supposedly was visited by them. he didn't stop, and as of a month or 2 ago, was still going strong.

>>2960997
To this day I still can't figure what actually gets them off their ass.
Pirate radio broadcasts and actual interference to important shit, sure, but aside from that, I don't get the logic they use.
I've tried reading through the published enforcement actions, but those documents are a little scant on details, and it just seems random.
Maybe it's like, sometimes an fcc janny gets pissed?
I dunno.

thoughts on mounting an antenna to your car?
i hear cb is dead, but scanning gmrs while on a long roadtrip sounds like fun

>>2961014
CB isn't dead, that anon was just a retard who couldn't antenna his way out of a wet paper bag.
Car whips are ezpz to get going.
Not the greatest gain in the world, but it's a mobile rig.

>>2961017
cb is dead

>>2961024
nuh uh

>>2961017
>CB isn't dead
I heard trucker channels basically are.

>>2961034
all the truckers in my area use murs and as far as I can figure, are using vhf ham equipment and amping the shit out of it

a lot of cb now is people who want to talk skip but don't want to buy a ham license for hf

if I set up cb right now, which I have a build in progress, I'm gonna make it a long distance base station for talking skip

imo driving around with a cb radio is not gonna be nearly as entertaining as driving around with an unlocked murs and gmrs radio

But sitting at home talking skip could still be a lot of fun

>>2961028
yeah huh.

>>2961037
same here, haven't heard a trucker on cb in over 10 years.

inb4 "your antenna" I can pickup super bowl morons all the time, and recently I heard a couple of old guys talking a couple miles away about boring shit a couple months ago.

>>2960888
Not yet but one day they will.

>>2961105
>same here, haven't heard a trucker on cb in over 10 years.
Same. All truckers in my region are using what we call LADD frequencies. A handfull of vhf freqs arounf 150 MHz using commercial radios, not amateur radio gear. However there is a small contingent of 4x4's who are slowly drifting back to CB this summer for local comms because they're getting away from the FRS/GMRS crowd and Baofeng kids.

>>2961145
>Not yet but one day they will.
What are the chances that the PA stage has the same weaknesses as a radar?
https://www.emsopedia.org/entries/specific-emitter-identification-for-radar-signals/
In any case, I would expect various agencies extracting voice prints of everyone who ever thouched a phone in the US, tying that voice print to the phone number and thus positive identification, and then apply that to voice over radio. They have probably done that for decades. Anything less is simply not credible.

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https://www.qsl.net/dk7zb/Duoband/dipolduoband.htm
This look good for baby’s first roof antenna? It’s to connect to my 5W handheld Quansheng. He says it should be mounted 280mm in front of a vertical mast in order to get 50 ohm impedance on the 2m band, but doesn’t state how tall the mast should be above the centre of the dipole so I guess it doesn’t matter so long as it’s significantly larger than the dipole.
I probably won’t make it with the extra reflector, I’m not looking for high directionality at the moment. First directional antenna should probably be something I can aim with trial and error without a ladder.

As for HF, I’ve done the HF receiving mod to that Quansheng so I guess I’m interested in an antenna for that too, but I’ve got all the stuff lying about for a PA0RDT active mini whip that I’ll probably make and put on the same mast. With a linear power supply, of course.

>>2961155
It looks good enough.
I'm assuming that the matching to the mast assumes that the masthead is at least as tall as the top of the antenna.
There's no reason the antenna couldn't stick up above the top of the mast, but that would change the distance value.

>>2961155
>>2961173
Oh now now I’m feature-creeping. If I put that HF mini-whip up there too I’d have two 14m lengths of coax going down to my room, so now I want to put a diplexer up there too. But now that I look even closer, that mini-whip shouldn’t be mounted on a metal pole, I wonder how important that is considering the coax going to it is grounded anyhow. Maybe I mount some PVC pipe atop my TV dish instead, that makes one of the coax lengths shorter.

>>2961147
We've been using transmitter signature fingerprints since the 60's. Every radio is unique and like fingerprints, no two are the same.

>>2961196
An obvious question is if the Chinese authorities have mandated unique fingerprints for each radio they export, carefully logged by an agency?
I guess yes. I just wonder if the preppers ever thought about it. Probably not.

>>2961294
These things are made by the millions for cheap and they transmit analog FM, plus the range is limited, you think a chinese ELINT plane will circle above your head listening to your coms ?

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>>2961296
>These things are made by the millions
Yes
>for cheap
Yes
>and they transmit analog FM,
Sure
>plus the range is limited,
Rather LOS
>you think a chinese ELINT plane will circle above your head listening to your coms ?
Nice sharp left turn there. Some of us do not have the memory of a goldfish in a too small bowl, and will remember Chinese balloons, Chinese secret rooms in embassies, and that satellites have been able to listen in on radio comms for decades.

>>2961298
ok so China will spend billions to listen to some rednecks in the woods, I guess buy Icom or Yaesu ?

>>2961300
>ok so China will spend billions to listen to some rednecks in the woods,
They sure will, that is the advantage of a command economy with a limitless supply of people who can do the job. Much will be automated, and getting a good voice print is important. They will of course hope for more important stuff such as mishaps on military comms.
>I guess buy Icom or Yaesu ?
Probably safer, same with HF. Icom 7300 Mk 2 looks interesting, would be good if Yaesu upgraded their FTDX-10, FT-710 to match, and best of all, FTDX-9000D with apps as was hinted at back in the day.
I am first planning on getting a KiwiSDR or the like.

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>>2961300
That is an option. But then the Japanese spy balloons will be listening to your net check-in's.

>>2961294
Good lord. To do so in a way that wouldn't get figured out by the first dude who dumps the firmware would cost more than the entire radio sells for.

>>2961301
Command economy doesn't mean limitless resources. All the manpower and materials spent on building Hongtu-2, putting it into orbit, and analyzing the baofeng signals is resources that could have been used for actual intelligence gains.
It's much easier to just pay some idiot $30k for classified information.

>>2961311
>Good lord. To do so in a way that wouldn't get figured out by the first dude who dumps the firmware would cost more than the entire radio sells for.
You need to look mor eon this, it does not rely on the firmware, it is intrinsic to the electronics, especially the PA stage. On the plus side, you can change the PA stage and then throw them off the scent.
BTW you know that WWII Morse code operators were also profiled by their fists?

Anyway, I wonder if anyone has dumped the firmware with an eye for hidden features, including hidden partition in the NVM.

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How many more fires will you all start just to make yourselves feel relevant?

>captcha: h4m

>solder up a nice bias tee with a capacitance multiplier to really stamp out those high frequencies
>see excellent ripple rejection before the RF choke
>measure after the RF choke on the coax connector itself and see a bunch of noise
I guess those axial chokes pick up a fair bit of magnetic field noise. I could try to lower it with a ferritic can over the tee, but that won’t work up in the antenna. I think instead I’ll wind a pair of toroids on these 8x16mm ferrite sleeves I’ve got lying about. With 5 turns I’m not measuring any appreciable inductance, so I think I’ve got my work cut out for me.

>>2961298
>Rhyolite/Chalet/Magnum
I hope one day someone will publish an in-depth and highly detailed book about these, and the Soviet equivalents, within my lifetime.

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>>2961453
42.

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Every ham is scared to make the 2200m dipole.

>>2961483
https://satelliteobservation.net/2017/09/24/a-radiotelescope-in-the-sky-the-usa-202-orion-satellite/

Not exactly what you were looking for, but does give some insight into the world of overhead SIGINT/ELINT collection.

I recently pulled my old mmdvm hotspot out of the junk drawer and set it up again for DMR. And while I know most hams dont take DMR seriously, the amount of traffic happening on brandmeister and TGIF is wild. I've set up a several large repeater groups as static talk groups, and I'm being blasted with irrelevant weather reports, medical stories, guys talking about UFO's, drunk guys driving around and arguing about everything, etc.
For those of you complaining that CB is dead, DMR and all-star might fill the void, at least while your at home or the office. Yes, DMR is gay because its not really radio and relies on major infrastructure. You also can't shit things up for fun like CB, because you'll get banned. But I still think its neat and there are non stop voice qso's happening 24/7. It filters out some retards as well, because they can't figure out how to set up a hotspot or program a simple code plug.

>>2961547
DMR where I am is mostly being used by cement companies, and quarries.

>>2961563
Its a commercial protocol. Hams have just cobbled together amateur dmr networks and tried to make it work for their needs despite its limitations. It was never intended to be used for amateur radio.
There's tons of quirks because of its commercial roots. The vocoder isn't open source, voices sound robotic, managing talk groups can be cumbersome, and basically every DMR radio is Chinese tier quality. Programming code plugs also has a learning curve, but its just tedious rather than challenging. The hardware has gotten much better in the last year or two, and its cheap.
That being said, the traffic on the big DMR networks is massive. Lots of people are using it.

>>2961547
>And while I know most hams dont take DMR seriously
I do.

>Yes, DMR is gay because its not really radio
Your radio is transmitting data to the hotspot or DMR repeater if it is in your area. Therefore, it's real radio. It just so happens to be:

>relies on major infrastructure
if you want to talk far and wide on either VHF or UHF. Otherwise, there's always simplex, which is what I use for family and neighbors since we don't want others with UV-5Rs, Qi Gong Jins K5s, and other analogue radios to listen in.

>>2961568
>That being said, the traffic on the big DMR networks is massive.
for you.

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the AM tower I posted a few months ago that originally listed near me for 400k is down to 280k now.

>>2961657
lmao in da YOOP of Michigan there was a government auction for a pretty tall radio tower(not the land, just the tower, shack, and generator). I'm not sure what the final bid was, but about 3 hours from it closing it was only at 100 bucks.

>>2961754
This is an AM tower with a shed that's falling apart and no aviation lights on the top. I'm sure to get this thing back to "legal" is going to be 100k. It is working and running, It played a hiphop station for a while, but the main selling point is the property is big enough to build a house on. I don't even want to imagine how much it would cost to demolish it.

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I’m about to assemble this HF amplified RX-only antenna, with some minor modifications, but it doesn’t say anything about impedance matching. Considering I’ll be using 15m of coax back to my radio, and listening up to the 30MHz/10m band, should I try and ensure the output is 50 ohm matched? Or does it not really matter?

>>2961783
Is the tower condemned? Keep it, load it up on 472 kHz. Be the rock crusher on that band.

I'd love to get into that small building and see if there is any old equipment or documents in there. I see the 2 wooden poles. I'm betting at some point in the past they suspended a wire antenna. Maybe an early AM station.

Sat dish is ready for drift-scan SETI at C-band frequencies.

>>2960584
Thanks anon I'll give SDR a look. I just want to be as ready as possible for when ww3 starts. I live in a relatively remote rural area a couple of hours from most people so need to check for intel on what's happening in the world and if anyone is heading my way so I can bug out. And it's not like I'll be able to tune into NPR for that. Once the government collapses there's gonna be alot of violence and I don't want to be caught in the middle of it.

>>2961842
If it's RX only, I'm not sure why it would matter.
Maybe I'm fundamentally misunderstanding something about radios, but If you're not going to TX with it, I don't see why that would be all that important.

Rigs should have more fancy buttonology, like this: https://www.youtube.com/watch?v=_3T-qhv57ZI

>>2962152
I was thinking maybe the antenna amplifier stage might produce some strange results (e.g. mixing) with reflected signals, and the received signal amplitude would be lower. But now that I attempt to calculate it, the output impedance of that transistor amplifier will be in the ballpark of 30 ohms, dependant on current gain and transconductance, which should be fine. If it was like 3 ohms then it would matter more.

Yesterday I hammered an aluminium rod into the ground beneath the antenna to earth it, since I heard antenna earthing is important for capacitive antennas like these. There’s a hole in the bottom of the antenna casing now for the wire, I figure it’s better for pressure and humidity to be able to exchange freely with the inside of the antenna, as opposed to trying to withstand the pressure and keep the inside dry enough not to condense when it’s cold. The antenna is supported atop a pipe so there’s no path for water to get up inside the antenna.
Also made some wooden brackets to hold that pipe.

Hope I can actually hear something through it in my suburban foothills, be it on SDR or on my handhelds. I’ll be building that 70cm/2m dipole soon too, which I have fewer doubts about.

>>2962453
Sounds like a solid setup.
Suburban foothills shouldn't be TOO noisy, I'd think.
Shit, I'm in a rural area that's been growing the last couple of decades, and ironically, it's noisier here now than in suburban areas.
Everyone in the burbs isn't running all kinds of farm machinery all day.
Oh well, on the upside I'm getting to where I can recognize specific tractors by their rfi sound. That's kinda fun when there's not much action on the airwaves.

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>>2961155
>https://www.qsl.net/dk7zb/Duoband/dipolduoband.htm
Wait on the topic of grounding, how important is grounding (or lack thereof) for a dipole like this? I see he‘a used a plastic box instead of a metal box for the SO239 socket and the base of the dipole itself, but with the metal bracket inside the box it’s hard to tell if the SO239 shield is connected to the square tube that the antenna is mounted on. It looks like there’s an insulator between the 70cm-band parasitic element and this bar, but it’s hard to say with the metal screw though it. Furthermore, if the shield of the coax is grounded elsewhere, would that have any bearing on the on the operation of the dipole, considering there’s no balun?

>>2962664
Oh and would it matter if the antenna mounting pole (it also acts as a parasitic element) is grounded? It definitely looks electrically connected to the square tube spar that the antenna is mounted to.

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I picked up some boat anchors today.
>Drake tr-4c
Need to grab a power supply off of ebay to see if it runs
>World Radio Laboratories Globe Scout 65 transmitter only
I picked this up because it was made relatively close to me and it's as old as my parents. I plugged it in and turned the filament gain on and the vacuum tubes inside glow. 40 watts of AM or cw. Need to get crystals to set the frequency.

>>2962687
Got any R-390's yet?
I saw one for sale here and was considering buying one. In the end, I resisted.

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>>2962713
I had to look that up. Probably not in my price range. I do need a receiver and a Dow Key though. It took me quite some time to figure out the mic jack on that Globe Scout. I did find this adapter to turn it into a 1/4 phone jack to plug a regular (non ham) microphone into. There won't be a ptt button, but flipping the lever from transmit to standby is apparently like letting go of a ptt button.
This is also my first radio without a vfo. So I had to learn about crystals. One of the two crystals that came with it just happened to be 7200 kHz.

>>2962687
Nice. While not a collector of boat anchors I do appreciate seeing them and hearing them on the air. It's like old cars.

>>2962713
Saw an R-389 in someones radio room a few months ago. I had no idea how exceptionally rare they are until recently.

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>>2962748
>I had to look that up.
My man! You haven't lived!
>Probably not in my price range.
You can find them on ebay, proce varies enormously and depends on how well aligned it is. The mechanical parts will scare the daylight out of a watchmaker.
>I do need a receiver and a Dow Key though.
I am considereing a KiwiSDR but I have found the Chinese semi-clone Web-888 SDR interesting. Listening on them on the web, it seems to be less noisy.
https://www.rx-888.com/web/rx.html


>>2962826
>Saw an R-389 in someones radio room a few months ago.
Clearly a man of culture.

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not janky at all...

>>2961657
How comfy is running a station I wonder

I've hit an educational roadblock.
In lessons and exams, we're told 75 ohm coax is the devil. 50 ohm is less lossy. 75 ohm just won't work. Ok, less impedance means it's better. Cool.
Fast forward and I spend hundreds on LMR400 because 'muh losses' only to find 600 ohm ladder line is far superior and you can make it yourself.
Was it all a marketing hoax?

>>2963273
Loss happens on insertion, the transition between the 50 ohm radio output and the 70 ohm cable, and the 70 ohm cable and the whatever ohm of your antenna.
If you add impedance matching, it will work.

>>2963273
You can use 75 ohms everywhere, some antennas are 75 ohms or thereabouts, but all equipment you’ll use will be 50 ohms. So you’d need impedance matching on all your equipment. For HF that can be a transformer, but for higher frequencies you’ll likely be stuck with frequency-dependant LC networks. Might still be worth doing if you have a bunch of RG59 or RG6 lying about.

It’s simplest, and often most performant, to simply have everything natively at 50 ohms.

>>2962687
>>2962907
>boat anchors
If I was so inclined, i'd get an AR-88, the first SW radio I ever saw. I was in grade 2 and playing at a friends place. His dad had one in a spare room and hated us touching it. I was drawn to it. The most memorable thing I recall was finding out 6 years later that the "machinery noise" he said was from the hospital was actually Soviet jamming I suspect was coming out of Vlad based on my location.

I'm an apartmentfag in a Dutch city looking for gay ass hobbies. Is this the general for me?

Made the mini-whip, but the SDR is showing me a bunch of noise that doesn’t move when I change the tuning, that goes away when I turn off the phantom power. So I’ll test it off a 12V battery, then see if grounding or charging the battery while it’s on causes any more noise, considering common-mode noise or ground-looping might be an issue. Then I’ll probably use a zener regulator, and bigger caps, and more chokes. Maybe common-mode chokes too. And probably swap to a transformer-based supply.

Also Jaycar RG58U is ass. The C/U is fine, but the U has really sparse copper braid atop foil, to the point where the Jaycar BNC crimps don’t grab tight enough without doubling over the braid.

>>2963491
>Is this the general for me?
Sure. And if your apartment is high up and with a good view, you might also want to look into RONJA.

>>2963491
netherlands has cool pirate stations

>>2963491
Maybe if talking about your prostate problems is gay.

>>2963491
Totally.
Radio is the bee's knees.

>>2961513
You know I asked this to various people, why can't I build a dipole for this horizontally and suspend it in the air between two mountain tops with cable. No one can say if it will work

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>>2962664
>follow tutorial to build a 2m/70cm dipole
>says to cut the aluminium tubes so they’re 936mm tip-to-tip, with a 10mm gap in the middle
>seems about right
>leave a few mm in the ends so I can file them down if needed
>lay it out on the carpet and measure impedance and SWR with the VNA
>narrow SWR dip to 1.3 and impedance of 56Ω
>at 177MHz
>slightly worse SWR dip at 456MHz
I feel like a retard, what did I do wrong? Will propping it up in the air change the antenna characteristics?

>>2963517
Hmm, the noise is present even when powering from a battery. I’m seeing three types of signals on the SDR readout. Those that move left when I drag the frequency bar left (i.e. real signals at that frequency), those that move the right when I drag the bar left (aliased strong signals, FM radio stations when listening to 10m), and those that remain in the same area regardless of how I tune the local oscillator. These ones are what only appear when the antenna has power, while the aliased FM signals and real signals seem to be visible regardless. Having a cheap shitty SDR really does make you second guess yourself a lot. I need to figure out a way of troubleshooting the antenna properly, so I guess that means making a local signal I’m capable of receiving on the antenna, and ideally viewing on my scope too. My function generator goes up to 13.5MHz, but the SDR doesn’t measure below 25MHz.

>>2963663
It will work but the problem with resonant antennas at those frequencies is that the bandwidth would be very small.
The best way would be to use a catenary and then suspend the dipole below that, a bit like the overhead power line for electric trains. And I guess you will find enough crazy people at Berkeley to either suspend one from the Golden Gate Bridge (a rather good match), or use the bridge as a reflector to a dipole adjacent to the bridge. You could of course got for a foled dipole for a greater bandwidth for so much added complexities that not even Berkely students would touch this construction.

>>2963491
>I'm an apartmentfag in a Dutch city looking for gay ass hobbie
one does not get assigned a hobby my npc friend. one takes on a hobby because it interests them.

>>2960581
I started poking at it again, and in doing some reading, I learned that NEC2 does not handle end fed elements intuitively. I still haven't figured out how to solve the problem, but at least I know what it is now.

>>2963684
Oh never mind it was that shitty coax alligator lead I guess. Or maybe it was an inconvenient length. Took it outside and vertical with no avail, but bringing it out front, propping it up on a wheelie bin, and plugging in the PL259 lead I ran under my house and it measured really well, both for impedance and for frequency, SWR was below 1.5 if I recall. The long lead means the graph is pretty jagged, I’ll have to buy some more PL259s, or at least a PL259 to SMA or BNC adapter.
Trust the plan.

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If any of you US hams got a kick out of cramming on Ham Study and leveling up, the FCC Commercial tests are also on Ham Study and the testing process is similar.
In a week or two of studying, you too can be FCC Radar endorsed.

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>>2964046

>>2964046
Very interesting. I didn't use Ham Study for mine: I just read the boring ass book then memorized the questions and answers.

>>2964058
Ham Study is free and the same concept as memorizing the book plus it keeps track of your progress and offers practice tests. From my experience when you're batting 80% on those, you're ready for a real test.
The FCC Commercial tests are about as hard as the General test (minus the first element which is Tech tier).
You pay $25-50 to a COLEM (VEC) for testing and the FCC's $35 per license. The license is good for life and tied to your same FCC FRN.
Just throwing it out there. I kind of felt sad after getting my Extra that there weren't any more FCC tests. Turns out there are. I've picked up a few commercial licenses and have a few to go.

>>2964046
What do I get outof it except bragging rights and an additional credential? I don't use radars nor care about repairing or maintaining the radios listed in the part that requires the license? Am I missing something like being able to use frequencies outside the ham band without consequence and a required business license?

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>>2964111
Welp, my adhd brain skipped over this part. Station must still be licensed.

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>>2964111
Realistically? Bragging rights.
From memory
>The MP allows you to operate a radio on a large vessel or one holding 6 + people
>The GROL allows you to fix maritime radio systems and aeronautic systems (landing systems, crash avoidance, etc) and is desired for railroad professions involving radio systems. Broadcast engineers used to need this cert
>Radar endorsement is to work on radar systems
>GMDSS operator/repairer allows you to operate or repair maritime radio rescue equipment (pic related)
>Radiotelegraph operate or maintain a maritime (coast or sea) station.

While we're talking radars, how do I build one?

>>2964237
Still at it? Not sure how many links you got but here is another one:
https://www.instructables.com/Easy-HB100-Amplifier/

>>2964253
You know he does it now just to troll you, right?

>>2964312
I knew that. And I had recently seen that webpage and thought it relevant to more people, and also it was good for a contents filled bump.

Also: anyone here got their IC-7300Mk2 yet?

Why do boomers talk about synchronous detection like they do with gold plated vacuum tube headphone wires? Is it just a giant meme?

>>2965095
>synchronous detection
I am missing a ot of context here but at least in the context of coherent CW, the synchronous detection lets you pull extremely weak signals out of the noise, even signals you will struggle to see on a waterfall diagram.
With a little stretch you could argue that receiving GPS signals is also a synchronous operation.

>>2965161
It sounds too good to be true is the thing, and it "sucks" on basically every radio.

>>2965163
That sounds more like synchronous AM. Never used it myself but sources suggest it is useful during fading.

>custom antenna on roof gets worse reception to local 2m repeater than stock antenna handheld held out window
you know, i took down an unused tv antenna to put this antenna on its pole
we didn't use that tv antenna because the reception from the local mountain was blocked by some big trees, and use satellite tv instead
the repeater is on the same mountain as the tv antenna
i am a moron

If usps doesn't deliver my antenna tomorrow that was supposed to be delivered Wednesday I am going to kill myself

>>2965336
How goes it, anon? Are you metering out coax or rope?

>>2965575
he's roping with coax, the ham way

>>2965737
How many turns in the coax does he need to do if he's going to rope with it?

>>2965737
>50 ohm termination

>>2965818
at least 6

>>2965737
If you use exactly a quarter wavelength of coax, the load on the ceiling beam goes to zero.

Anons i am an absolute idiot what do i buy to get into HAM? It seems really cool. Is it expensive?

>>2966134
First read the FAQ and go through the library. Then you need to decide on what aspect of the hobby you will go for: tech, social/chatting over the airwaves, competition etc. And then get a rig based on your needs.
You can get a single frequency Morse code rig for 3 dollars, it is hard to go cheaper than that. A good rig is about 1000 dollars.

>>2966134
>Is it expensive?
yes very.

>>2966134
A common regret in ham radio is overspending. The hobby is interesting and fun, but its not worth spending too much money on. Only a select few actually enjoy their rigs enough to justify spending more than ~$1500.

>>2966256
Ham would be worth it if there were more interesting things out there. It's just boomers chatting and exchanging callsigns and megachurches on broadcast channels. Not everything is that, but it's like 75% of what you'll hear. Not the kind of dark wood to explore I expected.

>>2966727
>It's just boomers chatting
Especially about tmi medical issues. The thing I enjoy more is experimenting with different antenna builds.

>>2966727
I agree. And if I'm going to have a rag chew that isn't CW, its almost always on 2 meters or DMR/allstar since that's where all my acquaintances are found.
I have more fun scanning and listening to commercial frequencies anyway; stuff like resource road channels, emergency services, highway crews, etc. Basically all the good stuff is analog VHF in my area so I don't even need to bother setting up trunked network scanning. Receive only antennas are also fun to experiment with. Since you don't have to worry about blowing up any finals, you can try whatever crazy idea you want and the only negative repercussion is the possibility of poor Rx. I'm just using a 5/8 wavelength vertical for my vhf scanner that I made from the center conductor of 75ohm coax and a fiberglass pole. But I'm getting the parts together for a homebrew discone.

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pretty sure there's a kid jamming gmrs channels and maybe another jammer in my area

how to deal with jammers? I'm gonna start using privacy tones. But I'm gonna set up a repeater soon, and the one kid has already shown his ass on the one local repeater and it has an input frequency ctcss but he figured that one out. So he could probably figure out how to talk on mine

>>2966256
Thankfully, a ham can legally make rigs. QRP is easiest but can still be very capable.

>>2966727
>more interesting things out there
Some enjoy amateur SIGINT work. It is demanding but they put the results on their blogs, fairly impressive stuff.

>>2966731
What happened to the omelette dude?

>>2966816
In canada there was a time you could call the canadian equivelant of the FCC (don't remember what it used to be called) and get the offender fined.

>>2966826
In america you can too, but unless you are a business or interfering with emergency services. They won't do anything. The FCC won't fine you in USA unless you have enough money to pay a 10k dollar fine (IE a business) or you have to be actively and regularly fucking with the police or fire department

If I called the FCC on this jammer they'd go "dang" and then hang up lol

I'm thinking of getting an LMR license and a frequency from the FCC to have all to myself. I'd also be able to use encryption as well if I had an LMR license and frequency

>>2966816
They won't do anything.
You'd have to handle it yourself.

Concerning passive repeaters:
Is there any reason to use an integer number of wavelengths of coax between the antennas?

>ctrl-f
>"nvis"
>zero results
NGMI

>>2966816
learn to RDF with a radio receiver that has a true signal strength indicator and a yagi antenna.

Or spend big bucks on a krakenSDR

>>2966134
doesn't have to be expensive. Just get a Quansheng K5 and a boat anchor like TS-940 with a chinese antenna tuner.

>>2966134
>expensive?
Go for /diy/ and it can be quite cheap. A lot of rigs are built around a Si5351 clock chip, a Sa602 mixer and a microcontroller with ADC.

>>2967034
Now you're just telling retards to build all-band signal jammers
There is a reason why people buy turnkey ham equipment.

>>2967039
>Now you're just telling retards to build all-band signal jammers
If you have a license you should now all about harmonics, splatter and filtering.

>>2966816
Locate the jammer and destroy it. He won't contact the police and claim that his superfuckingillegal jammer was destroyed.

>>2966816
Can you send a small electrical pulse over the frequency to destroy the jammer?

>>2967216
No.
You can fire off an EMP but there is nothing about such and EMP that can be described by the word "small." Many, such as explosivey compressed field generatores are strictly one-shot.
I cannot imagine you can evade impreial entanglemet after having used one.

>>2967219
Kek, this.
I mean, you could in principle make a circuit-frying device out of old microwave magnetrons, but that's going to be LOUD.

>>2967261
Loudness is very much a minor issue here. Since this has to work at some distance, there will be a spread, and you will castrate a lot of people, some will probably also go blind. Everyone with a license will know that there are parts of the human body that are easily damaged by microwaves, usually permanently so. People without a license are unlikely to be aware of this.

>>2960056
Is there a RF mixer to inspect a 5.2 GHz signal on a <100 kHz budget scope?

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>>2966858
>The FCC won't fine you in USA

>>2967393
You can likely make a crude unbalanced mixer with an RF diode or transistor, the oscillator and the likely required input amplifier would be more difficult to make. A single-pole low-pass filter will easily get rid of those high frequency local oscillator and original signal components, assuming the bandwidth of the 5.2GHz signal is <100kHz (it probably is not). You'll almost certainly want to use a scope that can see the full bandwidth at once, but depending on the signal modulation you may yet get useful information by looking at narrower parts of the transmitted spectrum at a time, so long as your anti-aliasing filter is steep enough to have enough attenuation between the pass-band and the nyquist frequency. And depending on the surrounding spectrum, such a filter might be a good idea even if the signal you want to detect is within your scope's bandwidth. Your scope may or may not have adequate internal filtration to this end.

>>2967039
literally just slap a tunable bandpass filter retard
>>/analog devices/

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I’m on a mission to establish presence on 630m through my apartment gutters even if it’s with WSPR

>>2963171
I love it

hello guyz
just got a Quansheng UV-K5 (V1, white lit screen) for free (bricked)
managed to unbrick it and I'm wondering if there's any insight on which custom firmware is the most goated.

ps: I'm new to this, I just happen to be familar with a couple of stuff since my father is a ham radio operator (with ~35 years of xp) and I study in STEM.

>>2968095
I use Egzumer’s firmware, but mainly because I did the HF hardware mod and that’s the only option.

hi guys.
i've been getting into shortwave for music collage purposes. i have some questions:

1. i've been using websdr, is there any benefit to buying my own tuner and antenna and seeing how it fares in the south of florida?
2. if i stick with websdr, are there any APIs available that give you control over the frequency. I think modulating that or modulating between a set of predefined frequencies could be useful for my purposes.
3. are there any AI tools that can detect bands with the best SNR ratio, or maybe that's just known by the data and AI is not needed
4. what are the best shortwave radios to get? i may eventually make my own but i have a lot more to wrap my head around

>>2968351
>1. i've been using websdr, is there any benefit to buying my own tuner and antenna and seeing how it fares in the south of florida?
Websdr is fine for reception, if you want to transmit you need your own rig. If you want to receive only and have it locally, you can buy a KiwiSDR (or the clones) which will also make other listeners happy. According to the map, there are 7 receivers in Florida:
http://kiwisdr.com/.public/
You can search using the search box or chose from the map:
http://rx.linkfanel.net/

>2. if i stick with websdr, are there any APIs available that give you control over the frequency. I think modulating that or modulating between a set of predefined frequencies could be useful for my purposes.
Not sure. With a KiwiSDR you can select various filters if you wish, needs some work to do though. Filtering out local broadcasting is often a good idea.

>3. are there any AI tools that can detect bands with the best SNR ratio, or maybe that's just known by the data and AI is not needed
I don't know of any AI tools but that isn't needed either. The general field is known as Cognitive Radios and you can also listen for reception of sounders that regularly sweep the frequency bands. Systems such as ALE (Automatic Link Establishment) select the best bands and frequencies by listening to the bands. Channel characteristics is another term that is relevant if you want to read up on the topic.

>4. what are the best shortwave radios to get? i may eventually make my own but i have a lot more to wrap my head around
Shortwave radio is in the normal use a receiver only, sure that is what you mean? I don't know much about it but there are two resources you can look into
This one is for shortwave listening with some tech details:
https://swling.com/blog/
This is a super technical review of receivers out there, recognized by the industry:
http://www.sherweng.com/table.html

>>2968351
>what are the best shortwave radios to get?
define "best"? there is no "best". there is only the radio that works for what you want to do.

>>2968388
thanks for your response. yes, i'm only interested in receiving signal at this point. though i do have an idea to record some received signals and transmit them back using an am transmitter for some local feedback stuff but i'm not quite there yet. kiwisdr seems good.

>>2968416
i guess the antenna matters the most anyway. i just mean for SNR but i guess features too. it would be cool if there was one with a built in tape recorder.

>>2961145
LADD 1-4 is popular in BC Canada. Where are you from? or rather where have you heard it being used?

>>2967537
Thanks, message received and decoded completely!
It's likely QPSK and higher bandwidth... You guys successfully repurpose common home radio equipment for own projects? The building blocks is right there, what could the issues be?

>>2968497
>The building blocks is right there, what could the issues be?
...inside a Faraday cage

>>2968497
>repurpose common home radio equipment for own projects
It’s all proprietary ASICs these days. Occasionally they’re open to hacking like the RTL-SDR dongles, but that’s very much the exception and not the rule.

Nice to see more diversity in amateur radio.
https://www.youtube.com/watch?v=4gVxeqEr-fY

What does the sync button do?

>>2968563
A few Japanese female hams have been on the net for years already. And long before that, many telegraphists in the merchant fleet and the shore stations were often operated by women. Also in the military there were many female Morse code operators and I heard also of female only barracks. Recently, the US has reactivated Morse code schools and you will find many women there. These days, many of the high speed Morse code competition winners are east European women.
I guess you could say you are a bit behind the curve, anon.

>>2968630
and yet I rarely hear women on ham bands.

>>2968632
Because if they use phone, they're immediately swamped by thirsty boomers wanting to talk to her.

>>2968632
I knew all my fellow Morse code operators by their fists during training, all were men. I never knew you could determine if a fist was female.

>>2968674
What's a good way to train receiving?
I've been trying but I quickly get overwhelmed.
Is there some technique or do I just need to listen to a generator 24/7?

>>2968698
Start with slow code, a few characters at a time. Never try to think about the code, do not rely on the mnemonic between Morse and the characters. Instead, rely entirely on the rythm of the Morse code (the character V must be the simplest one). Master these characters before you add new characters, probably digits at the end.
Up the speed slowly to about 11 WPM, get the charactyers down reliably, and then push past 12, that is the hard part. Just keep on grinding until you do, and once you do it will feel very differently. Once you get past 12 you will quickly go up to 20.

>>2968768
This is really dated advice. If you learn characters at less than 20wpm, you're only hindering your progression. Instant character recognition is a far more efficient method to learn code. Otherwise you'll struggle at high speeds.

Here is a prototype of the new TenTec Phoenix. Looks like one heck of a nice radio. I put my deposit down a month ago to get one of the first 100 units. They are hoping to get them out before Hamvention.
https://youtu.be/_US4pTooU8M?si=ewcc3gwasu9SEtad

>>2968794
looks cool.
what's the benefit of a $4000 radio

>>2968632
The president of our local ham club is a woman so she's on the weekly net most of the time. Her husband got her into radio and I get the feeling she's the president mainly because no one else wants to do it.
>>2968639
Haven't seen that be an issue in our local club but that probably is the case because her husband is also a member and 50 is generally the age floor. When I was part of a hacker space, men lost their minds when a woman would show up, even if she was at best a four.

>>2968845
>looks cool.
Seems to go the DDC + FPGA route which is not cheap but should be performant.
>what's the benefit of a $4000 radio
High ranking on this list:
http://www.sherweng.com/table.html

Then again, for that sum I had expected a GPS diciplined oscillator and timer. Good timing is essential for certain digital modes.

>>2968845
bragging rights at the next net meeting.

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What could this be?

I am still new to this and I see a lot of weird stuff that I can't decode.

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After a Day of kerchunking Repeaters, you look outside your window and see Bean with Beam.

>>2969232
that cluster and the left one, dots look like a sync clock.
measuring the time could give a clue

i have a qwestchun

so i have this radio and and when it transmits on frequency A, the A*2 A*3 A*4, A*5 harmonics are very loud. actually much louder than A itself.

the rf output on A is very weak since the chip was never meant to send on that frequency.

to remedy this, can i do the following?

first, put a low pass filter just above A.
second, put an rf amp AFTER the filter and before the antenna

like this:
Radio -> LPF -> Amp -> Antenna

will this do it?

>>2969354
Just get a better radio, holy shit. You'll end up frying your amp using that piece of shit.

>>2969354
>actually much louder than A itself
That is a major error, is the low pass filter even attached?
And yes, a low pass filter (or a band pass filter) will tidy up the harmonics and also provide a stronger signal where you desire it to be.
The order you want is this:
Radio -> LPF or BPF -> Amp -> Antenna Tuner -> Antenna

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>>2969423
its a quansheng ukv5 and its not supposed to be txing at the frequency that i would like it to. the modified firmware allows it but the hardware is just not made for it.

so, i'm thinking about how to fix this if possible.
here is a screenshot of one of the videos describing this problem.
>https://youtu.be/ydf4jsZpaPw?t=111

>>2969444
>>2969423
so, obviously, i'd like to smoke 6 3 1 2 4 5 8 and 9 and keep only 7 and maybe even amplify it a bit.

>>2969444
>trying to output 10m band on a quansheng
wow that's neat but pretty ass
might be tough to prevent yourself from frying the internal amplifier, any filter you put on the end must not only allow one harmonic and block the rest, but also prevent those big harmonics from reflecting back too much, no clue how you'd do that but quarter-wave lengths of coax are probably a good start

mess about with filter designs in (lt)spice, that's what i'd do

>>2969450
why quarter lengths of coax?
is the idea to dissipate these harmonics as heat?

you might have noticed, i'm not very knowledgeable. i understand why you'd need low pass filters or amplifiers but i'm a noob when it comes to side effects and other more subtle things.

i thought that a low pass filter gets rid of them and have just assumed that they get converted to heat which would warm the filter up and that would be the end.

>>2969450
i found this: they seem to talk about this.

https://www.quora.com/What-is-reflected-RF-power

>>2969450
i just learned that there exists absorptive filters. different from reflective filters.

apparently they "eat" the harmonics instead of reflecting them back.

i bet they are more costly but worth looking in to. maybe they can be built.

>>2969450
here is more:

https://www.microwaves101.com/encyclopedias/reflectionless-filters

this is above my league but looks interesting.
>https://www.microwaves101.com/encyclopedias/reflectionless-filters

there are even some schematics there based on research by two guys.

can a filter be selected for maximal return loss and thus save the internal amplifier?
i read that impedance matching is important. what about that?

i know many would say the poor quansheng is not worth it but i still want to get my head around this.

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Amateur radio used to be a respectable hobby. Apparently the cucks have discovered it though.

>>2969454
>why quarter lengths of coax?
A quarter length of coax will turn a short-circuit into an open-circuit as far as impedance matching goes, but not have this effect on the harmonics of the wave, so it's a method of differentiating the signals from one another. Some diplexers use this techniqe instead of stacking a bunch of LC elements. But I can't really imagine how to use this for your application.
>is the idea to dissipate these harmonics as heat?
Yeah, just feeding them into a fully real 50 ohm resistance. The simplest method would be a filter that just selects for your 10m signal (low-pass or band-pass) allow just that 10m signal to pass through to an amplifier, while in parallel there would be a high-pass filter that allows all the harmonics go to a 50 ohm resistor. It's a few dollars worth of electrical components soldered atop some copperclad, the enclosure would cost more. Though I'd want to use a VNA to verify it.

Though if you instead want to attempt reverse engineering your radio to reduce the harmonics some other way that could be worth persuing too, and I'd consider attempting that on one of my two UV-K6s. Having an amplifier dongle would be kinda irritating.

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>>2969454
>>2969531
Oh hey, someone already reverse engineered it:
https://github.com/mentalDetector/Quansheng_UV-K5_PCB_R51-V1.4_PCB_Reversing_Rev._0.9?tab=readme-ov-file
Looks pretty complex, but I can't see any reason why there would be such large harmonics. Harmonic distortion is caused by lonlinearity, if the transistors are well-biased for 2m and 70cm, they should still be biased at other frequencies. It's just the filters that will make a difference, maybe that ends up changing the bias for low frequencies I guess?

>>2969534
>>2969531
thanks.

yeah these uvk5 radios are fascinating. cheap and open. i remember looking at hackrfs but those are crazy expensive and the rtl-sdr is a rx only so these quanshengs are a good middle-ground.

>>2969531
check this one, might interest you.

https://github.com/kamilsss655/uv-k5-firmware-custom

allows meshstatic style text messenger

>>2969560
>yeah these uvk5 radios are fascinating. cheap and open
It seems like they could be improved though. They're designed to just be used on 2m/70cm, with some capacity for RX only on FM broadcast and maybe aviation bands. But the chip they use, the BK4819, is capable of transmitting on a much wider range of frequencies, though I think it's FM only. It surely wouldn't be too tough to create a (handheld) radio with the same chipset but a wider-band RF front-end to allow it to be used on far more of the ham bands.

>>2969615
>check this one
I'm already running HF-modified Egzumer on my radios.
>allows meshstatic style text messenger
Neat, but the whole reason to use a mesh network is that other users of the network act as your relay points. There's little point if you've invented a new protocol that has barely any users. The best thing about LoRa is that it's widely adopted. The worst thing about LoRa is that it's built atop proprietary hardware that's difficult to clone and not as cheap as it could be, but I guess that helps it be usable by non-hams.
Meshtastic itself has some issues, some of which are solved by Rnodes. Chirp spread spectrum is very cool though, I'd like to see more use of these high signal budget protocols that can be received below the conventional noise floor.

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>>2969653
>but the whole reason to use a mesh network is that other users of the network act as your relay points.

thats what it does

but i agree that its better to focus on the most used already existing network.
if someone could literally port the meshstatic protocol over to it, that would be even better.
also, there seems to be encryption support.

>>2969444
>>2969450
This looks somewhat promising:
https://www.changpuak.ch/electronics/calc_16a.php
Very abrupt fall-off after the pass-band.

>>2969663
>thats what it does
It relies on other people having modified Quanshengs.
>port the meshtastic protocol
That's where the proprietary nature becomes an issue. Not like you can't reverse engineer it, CNLohr figured out how to transmit it via an ESP32's GPIO toggling after all.
>encryption
Isn't that explicitly not allowed on ham bands?

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>>2969653
https://github.com/kamilsss655/ESPRI


look at this.

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>>2969664
>Isn't that explicitly not allowed on ham bands?

>>2969665
Neat, but I bet you could make it 4 times smaller by soldering the EPS32 chip directly onto the main board, instead of using a fat dev-board. Or at least using a WROOM-32 module. None of the features look particularly useful to me, the UART link is surely pretty handy when it comes to interfacing with the radio via your PC but I already can do that with a USB cable.

>>2969668
yeah it looks like shit but at least it shows that its possible.

i would make simple cables going to a little case on the back which would attach to the belt clip holder which would contain the board.

>>2969671
Might be better off making it a modchip that goes inside, but it is pretty tight in there. The next Quansheng radio is said to have more memory and probably UART on its USB C charge port, which might mean we no longer need an external MCU.

>>2969677
>which might mean we no longer need an external MCU

how so? excuse me, i'm just not following.

>>2969679
As in, all the things that were programmed into the ESP32 can instead be programmed with custom firmware into the main internal MCU. For wireless communication you'd probably be able to cram a little modchip in there. Micro-SD slot, not so much.

>>2969681
ok, basically sufficiently advanced and programmable out of the box.
lets hope for that then.
sounds good for sure

>>2969664
I'm not a lawyer but it appears that encryption is ok if you are using it to experiment with how well it propagates over a radio signal and aren't trying to actually communicate information that is hidden by the encryption. So if you broadcast your station id as usual, announce an encrypted payload, and that payload is either sent in clear text before or after the encrypted text or you declare it to be a dummy payload, you should be fine legally. Broadcast the decryption key if you want to be extra careful about legality. If you're using it as an actual secure channel, that's going to be illegal on amateur bands in most cases (for the US).
If you want to have secure comms in a SHTF type situation, you're not going to be worried about the boomer patrol complaining to the FCC but you will worry about if your system works correctly if you have no practice using it. Experiment legally with clear intent and then keep the knowledge in your backpocket for other uses if you ever need them.

>>2969685
Well that's one of the upsides of comms that don't rely on ham licenses, like CB or LoRa. Also makes them more accessible, which is important for a mesh network that gets better with more users.

anyone using JS8 here?
it looks like a good protocol.
what is the catch?

>>2969685
>I'm not a lawyer
stopped reading there because I'm certain everything after that would be bullshit.

>>2969685
>If you want to have secure comms in a SHTF type situation, you're not going to be worried about the boomer patrol
You should be worried about being detected purely because you're transmitting. It's like walking around in the dark with a lantern thinking no one will see you because it's dark.

>>2969945
Commenting on a post without reading it is a time honored tradition.
>>2969966
I'd hope no one would be stupid enough to broadcast continuously if there are roving bandits about looking for them.

>>2969531
about the harmonics:

do you think it would be possible to bypass the built in amplifier altogether (to avoid it amplifying the harmonics) and to amplify the signal outside of the radio with a properly tuned amp?

>>2969531
>>2970029
forget about it.
i even found a tutorial to modify it for CB band tx but you lose some vhf and uhf functionality
so i guess i will go for the hf full band mod instead.
seems less destructive

>>2969531
damn, i just checked the si4732 chip and its receive only which is not what i thought.

>>2970029
Seems feasible, you could follow the RF ASIC's datasheet to ensure the RF output pin(s) see the right impedance, though doing so would likely mean having to disconnect the existing amplifier properly. If you put the new amp PCB in an extra thick (3D printed) case you can likely get it to still be nicely handheld. But maybe you can pass the netlist for the amplifier into GPT or some shit and get an idea why you'd be getting nasty harmonics. Do you still get those harmonics even at very low transmit power levels?

I had a radio dream this night, that's the first time.
Strange and long dream, I was on holidays in some mountains with my family, at some point I was alone in a village and I start talking radio with a guy and a middle age woman comes by and ask to listen to radio, I knew I had no radio in my huge backpack but I manage to pull out of it a chink radio that can receive CB.
So I get this handled, it has a huuuuge antenna, like 10m long, from time to time it came entangled with some wires in the street or some trees, we receive some chatting on CB channels, some music even, on SSB (that was important in the dream) and I don't remember how that ends.

>>2970081

i'm not supposed to use chatgpt.
when i get back to my city there is a local electronics shop he is an old radio guy. he sells most things from components to devices.
i'd have to ask him a few questions when i get back.
thanks to you i already have quite a few leads. so thank you for that.

>>2970003
>Commenting on a post without reading it is a time honored tradition.
starting a post and admitting you don't know what you are talking about.
standard.
anyone who starts a sentence with "I am not a X" is GOING to say bullshit. every time.

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>>2970036

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>full HF mod

>>2969534
Do any of the Quansheng mods transmit AM? That chip is for FM transmitting only, but it is able to modulate its transmit power at least to some extent. But more useful than that would be the ability to transmit and receive SSB as well. I wonder if there are any RF ICs that can do all of that? How would one even search for them? Or is it more cost effective to use an SDR?

>>2970161
Stop being stupid

>>2969685
Meshtastic has a ham mode that turns off encryption.
Or just yolo it. If you're on 70cm or above literally nobody is going to care as long as you're not stepping on repeater frequencies.

A bit of an unusual query, but anyway: I flew internationally the other day, and I have a hereditary disease that caused a medical emergency while in flight. They had a wheelchair waiting for me at the gate, even. It was apparently more dramatic than I thought, because I was passed out. Does anyone know of any archive or similar, to listen to recent ATC/flight radio traffic at different locations?
Would like to see if I can find anything related to the scenario I was in.

>>2970187
I assume such a thing exists, because some autists tracked MH370 using spurious reflections discovered in archived radio data. Look into that project and what archives were used. Chances are some online SDR receivers like KiwiSDRs archive some signals. Otherwise you might be able to request that data from your air traffic control authority, or directly from your government via a FOIA request or equivalent, in the same way people do for bodycam footage.

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>Meshtastic

>>2969685
>I'm not a lawyer but it appears that encryption is ok if you are using it to experiment with how well it propagates over a radio signal
Are you sure you meant encryption and not scrambling? As the FAQ points out, radio comms is still regulated by a slew of cold war laws and rules, and you would have quickly learned that encryption is not allowed. Scrambling is often used to improve channel capacity, especially in mobile phone systems. GPS style Gold code PRNs are effective also in encryption but would be permissible if the full specs for complete decoding was made publicly available. Same with complex protocols like FT8, JS8 etc. and Forward Error Correction (FEC) as also used in modern digital modes.

>>2970187
liveatc.net has recordings of tons of ATC traffic a tons of airports. but no index of incidents they do have interesting recordings that people have flagged or uploaded.
https://www.liveatc.net/recordings.php

>>2969685
there are no roving bands of fcc snitches recording every transmission rooting out people using encryption and scramblers.

laws are for punishing people caught doing crimes not dragging johnny out on the street and executing him right there... oh wait.

well NOW they are.

>>2970187
if you know the date time and airport, and the airport is on liveatc you can download a recording but you have to know the time in UTC that the incident happened for that airport.
https://www.liveatc.net/archive.php

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>>2970226
>no roving bands of fcc
Now guess why that is, see >>2961298

>>2970261
BRB, moving to northern Greenland for covert shitposting,

>>2970271
>Greenland
Anon, I have some bad news for you...

>>2970226
Sure, you can break the law and there's very little chance of getting caught unless you're going out of your way to taunt the fox hunt boomers, but that doesn't make it legal, just low risk. It's important to understand the difference if you're going to do it.

>>2970298
the fcc only enforces it's rules (not laws) for large businesses that break them.

>>2968435
>it would be cool if there was one with a built in tape recorder.
The old Radio Shack DX392 has a built in tape recorder. Not many portables had them. A couple of obscure Sony models and the Sangean 818CS that had a built-in tape recorder. Many models withouty built-in recorders had a Line-Out jack where you can hook up an external recorder.

>>2968465
Sorry for the late reply. Vancouver Island. LADD-1 (154.100 MHz) seems to be the most active for me and it's mostly guys chewing the fat on random work related topics. However I don't do extensive monitoring of those channels. Sometimes I hear them for a short duration when they pass through my area while buddy driving.

Is it legal in the US to set up cell phone jammers on your own property for religious reasons? I want to build a sort of pagan shrine in my backyard where I am truly electromagnetically out of contact even from satellite phones. I figured hams would know.

>>2970400
What practically matters is that you don't interfere with other broadcasts. If you're releasing spurious emissions that nobody will be bothered by, (i.e. contained within your property) then it's probably not a big deal.

>>2970400
>electromagnetically out of contact
Shielding is better, cheaper, safer and also legal.

>>2970400
Active jamming is illegal, no exceptions. However, you can passively attenuate to your heart’s content.

>>2970204
>>2970225
>>2970228
thank you very much for the help, anons. will check this out

>>2970446
What is passive attenuation?

>>2970478
He means tinfoil.

>>2960239
I live in eastern europe and the vast majority of public services (including police) still rely on NFM. Only in a few cities maybe they have TETRA, and its adoption is excruciatingly slow. I listen to them very often on my 125xlt, and I was also constantly up to date when local fire watch was coordinating their actions when entire region got flooded.

>>2970325
Starlink?

I’m pretty sure you meant that as long as you give the government the keys, and/or a direct tap into the unencrypted trunk, then it’s all fine.

>>2970481
I meant what I said. you pulled that out of your ass.

>>2970208
Sure:
https://linuxgizmos.com/rakwireless-rolls-out-wismesh-rak3312-meshtastic-lora-starter-kit/

>>2970481
So, if you’re implementing IP over radio or microwaves, you can’t use SSL?
That makes no logical sense, like the ITAR rules.

>>2970480
I'm my small Canadian town, its all analog VHF-HI except for RCMP (police) who switched to P25E almost a decade ago, so we can't listen to them. But everything else is unencrypted so there's still lots of things to hear. There are a couple conventional DMR and NXDN commercial users, but its all boring stuff mostly.
This time of year I like listening to the snowplows as they try to keep the mountain passes clear. During the summer, there will be lots of wildfire radio traffic. And while I can still hear fire and ambulance, I really do miss listening to the cops. They are actually kind of retarded so it was a blast listening to them fumble while breaking up bush parties, catching drunks, etc. But that was 10 years ago, simpler times. Now they probably just round up fent junkies and natives.

>>2970815
Do they at least receive regular radio frequencies so you can call for help or something?

>>2970882
I assume you mean the police? They use encrypted P25 conventional in my area. Its still a VHF-HI frequency, but it sounds like garbled digital noises on the scanner. You can't listen to the radio chatter without an encryption key. They have some unencrypted back channels for interagency communication, but its rare to hear those transmissions.
And that is just a sign of things to come. They want to move all the public safety frequencies to P25E, so eventually none of it will be in the clear. But the governments here are poorly managed, so they don't have the money to switch from analog to P25 in rural areas right now, but I suspect within 5 years the transition will begin.
Rail in North America is also slowly preparing to switch to unencrypted nxdn; that'll be neat when it finally happens.

>>2970882
>Do they at least receive regular radio frequencies so you can call for help or something?
If you don't have cell-phone coverage, you use the CB emergency frequencies. Just because the police swap from one protocol for internal communications (in a frequency segment that nobody else is allowed to use) to another, doesn't in any way change how they receive emergency communications from people not in the police. If you hopped on your baofeng and tried to interject in the police radio chatter to tell them about a burglary, they'd sooner arrest you than the burglar.

>>2970815
>>2970902
I misunderstood the question. If I needed police and I was out of cell tower range, I'd try to get someone on one of the VHF repeaters to call 911 and relay my info. Or ch 9 CB band, as suggested, but CB is mostly dead here so that might not be of much help.
There isn't any reason to ever transmit on the police frequencies in Canada. If they caught a pirate on their frequencies, I suspect the RCMP would get creative and find multiple federal charges lay on the person. It would be an absolute legal nightmare to navigate. You would probably spend some time behind bars.

>>2970928
>Or ch 9 CB band, as suggested, but CB is mostly dead here so that might not be of much help
I was under the impression that emergency CB channels were monitored by the same people who monitor for EPIRBs and the like, maybe including government satellites. I guess police cars and such might be monitoring them, but if you're not within range there's not much point. Especially for UHF CB, which is much more popular in some countries.

>>2970936
They probably have a CB radio collecting dust in the station, but nobody is ever there to monitor it. We have maybe a total of 12 police officers, and you typically need to call dispatch (which is 1.5 hours away) and arrange to have a constable meet you at the station if you need something that isn't emergency related. They hire old army vets to watch the cells, so there isn't even an actual cop guarding the drunk tank.
The EPIRB and marine rescue stuff is all handled by the rescue coordination center in Vancouver, and I'm a half days drive from the Pacific ocean. They only monitor marine frequencies anyway to the best of my knowledge.

>>2970941
What about personal locator beacons for hikers?

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>>2970936
>I was under the impression that emergency CB channels were monitored

>>2970989
The only ones who monitor it here are truckerfags and larpers.

>>2970897
>>2970902
Yes, I meant the police.
And I didn’t mean frequencies exactly, but I meant if regular police radios can pick up unencrypted traffic (e.g. CB ch 9) or maybe they are always tuned to pick it up simultaneously with their regular encrypted chatter.
Some of the truckers use CB around the rocky mountains here for blind turns and whatnot and you can hear them signal intent or issues (i.e. rockslides)
Anyway, I always just kind of assumed police and other emergency services would pick up ch 9 (at least) since it’s so well known and ancient.
I have two CB base stations I bought recently with some handheld ch 14 cb radios for emergency purposes but I’m worried I wasted my money.
I have some gmrs (even before they were legal in canada) but I don’t think there’s an emergency channel and they are weak and short distance and generally toy-like, so I don’t know what to do now.

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>>2971099
The LADD channels seem to have the trucker chatter now, anon. If you want to listen to the drivers through the rockies, program LADD 1 through 4 into your radio. Also program in ministry of transportation 1 through 4 if you're in BC; then you can listen to snow plows and avalanche control.
CB sucks now. The only things I hear on CB are swarthy Americans running footwarmers for skip. Audioooooooo. I actually love the 11 meter guys, I'm just giving them a hard time.

>>2971241
Thanks for the info on LADD and looking that up, I also found out about Alberta Wide. I should probably invest in a VHF radio then, you can get 50 watt jobbies. Probably don’t need a licence, I’m pretty sure a lot of truckers haven't even been able to pass driving licenses.

>>2970941
>rescue coordination center in Vancouver
You mean RCC Victoria. :-) Correct, they only monitor marine VHF 16 and DSC. MCTS Ucluelet & Prince Rupert also includes marine HF 2182 kHz on their watch on the western approaches. Vancouver VTS is concerned mostly with traffic in their inner harbour and Georgia Strait up to northern Vancouver Island thru a network of VHF relays and links.

No official entity in BC monitors CB, not RCMP nor CCG. CB's aren't allowed in RCMP vehicles due to internal standardization rules. The last time I was at E-COMM in Vancouver (2004) there was no CB capability. I don't know if VECTOR does but I have doubts.

However I do know a radio enthusiast at a lightstation located in Queen Charlotte sound who set up his own CB radio. Monitored ch19 for years and never heard anything so he left it switched off for a year. Then one stormy night in early 2000's he was on watch and told me he suddenly felt compelled to turn it on. He doesn't know why. When he did he heard a very weak signal in the noise calling for help. Turned out to be a power boater from the States who suffered engine failure and was in danger of being swamped by high waves.

>>2970975
COSPAS-SARSAT monitors that. When they get a hit they determine the general location and then contact the appropriate SAR for the region with the details. Here in Canada RCAF and CCG have RDF equipment for the beacons but don't normally monitor it unless it's part of their mission profile.

>>2970936
Remote places such as Alaska and Australia have emergency frequencies on the HF band. In Australia, the Q-MAC HF-90 was popular for such use in the outback since it supported most of the HF band and had SELCALL.

>>2971474
What happened to the power boater?

Anyone into LoRa or meshtastic? Considering getting one of these to use as a router node because the closest users I can see are 20+ miles away. Realistically how far can these little things reach with a decent antenna on hill?

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>>2971847
I'm stupid. These 1W T-beams from lilygo.

>>2971847
>how far can these little things reach with a decent antenna on hill?
a friend managed 100 - 150 kms reliably, no obstacles, remote node is on a mountain

>>2971847
I would set one up but I would be the only one using it and there's no one else near me that uses it. I like the off-grid aspects of it.

>>2971847
I have a fair bit of experience with meshslop.
At 20 miles, you have to actually do best practices, you need a hill, your other end needs a hill, you need fresnel clearance, at minimum 3 meters between the base of your antenna and the ground or any other object. You need perfect line of sight with up to 40 metres of fresnel clearance towards the middle of the span.
1w is ok for a portable node you walk around with, that unit is shit for a router node. Sadly I wish there was a clear answer at the moment but the market is still pretty schizo about 1-2w gear.

The single most important thing before anything is is altitude and fresnel clearances, the next important thing is your antenna, the third import thing is a LNA, the fourth is your transmit power.
Like I have a node on a mountain, it is mounted on a tower and has a fairly inexpensive $500 antenna and an amplified node and produces like 12.6w eirp (idgaf). it's cool and all but like nothing else can reply back, occasionally ill run across someone posting about seeing it in like a different region's discord like 300km away and it's kinda funny to me.

Like I'm not saying don't get it, but it's also out of stock at the moment for miles users. It generally isn't going to do much more than a heltec lora32 v4 you can get for half the cost.

>>2971848
>1W
I was under the impression LoRa used milliwatts if not microwatts. Is this a thing you can do with a ham license?

>>2971728
He was rescued by a CCG boat out of Port Hardy. If I remember correctly other assets were called out: a plane from 442 Squadron (Comox) was dispatched and I think a commercial vessel transiting off Cape Scott diverted but was not needed. The boater was out of his league for boat size and the time of the year. He did not have marine VHF.

>>2971944
I believe he’s using a idgaf license.

>>2971944
It's ism band, you are allowed up to 1w conducted and 4w eirp.
Though there are some psd limitations and antenna rules that limit you to less in almost all sòytastic bands but no one abides by that.

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Guys, I have a Cobra 148 GTL and I think my mic is busted. When I key it, the needle moves, but like I’ll talk into it and I get nothing. No needle move past that point and the pa doesn’t work.

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What’s the longest range mobile setup you can possibly do for a CB radio? Like with an amp and stuff I mean.

>>2970481
>>2970730
Only AMATEUR radio communications in the amateur bands have to be unencrypted.
If you go get a business license for some frequencies, you're almost always allowed to use encryption on the frequencies your license covers.

The rationale behind banning encryption/scrambling/etc from amateur radio is that if encryption were allowed, businesses would start using the amateur bands for their own purposes because there would be no way to tell. Also, some countries really dislike their citizens having access to encrypted communications and would probably just ban ham radio if encryption were permitted.

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Got my train monitoring setup dialed in for decoding the various telemetry signals from the freight trains that pass through my area. I'm able to monitor about 80km worth of track using a 5/8 wavelength vertical with a ground plane made from romex. I'm going to build a more directional antenna to help with weak signals. Interestingly, a 20 year old scanner is working better for this than a sdrplay... Go figure.

>>2972236
Swap mic with one known to work. If it does, the switch in your microphone is broken.

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>>2972618
>Interestingly, a 20 year old scanner is working better for this than a sdrplay
I'm not surprised. I recently realized that some older gear in certain usage works better than modern day software stuff.

During the recent RTTY round-up we used some late 80s/early 90's gear and found it worked noticably better than a modern laptop with MTTY and an Icom 7300.

>>2972566
Worldwide. You can achieve that with a couple of watts if propagation is good or 1 or 2 kw when it's bad. The amount of copper involved will get interesting, you'll have to connect every part of the vehicle with thick braided wire but also avoid ground loops.

>>2972618
That's neat, about the sdr I can't remember wich one of the sdr play or hackrf is fucking deaf. Maybe both. They are very easily overloaded, maybe without preamp, noise from all the computer thing through the USB is horrible.

>>2972678
digital to analog to digital to analog to digital always turns out shitty.

>>2972653
There's lots of VHF activity here, and since I'm in a mountain valley, we deal with scatter and weak signals. I can pull out more of those weak signals with my 1990s Azden 2meter rig than I can with my modern Yaseu dual bander.
The Japanese in particular had a tendency to over engineer their radios in the 90s. That's the reason I'm so fond of the 1990s era Japanese radios; especially the single banders. There's nothing available today with the quality of my Azden PCS unless you get into commercial gear which is double or triple the price.

>>2972679
I did try running the laptop on battery power to see if the power supply was raising my noise floor, but it really didn't make a discernible difference. I think its probably a combination between limitations in the software and cheap hardware that hinders the SDR play in this scenario.

>>2972719
It's likely the screen backlight circuit causing the rise in the noise floor.

>>2972679
The hackrf is only 8 bit resolution so I’m guessing it was the deaf one, the sdrplay is 14 bits so harder to overwhelm if your input gain isn't tuned in perfectly, or if you’ve got big unwanted signals in your filter passband.

Hypothetically speaking, what would happen if someone from the USA spoke on the Canadian military’s radio waves?

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and DIE!

>this id the Storm Net taking any traffic regarding this winter storm
>net control, this is W1NTER. We have 2ft of snow, and we need su-
>CQ WINTER FIELD DAY CQ WINTER FIELD

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Do people still talk on shortwave radio?
Is it autistic where people use their call signs or does nobody care anymore and can you just forget about a license?
I’m thinking about either getting another CB radio to put in my home or either getting a shortwave radio.

>>2972719
FB on the Azden. I echo your sentiment about that era of radios.

Are you the one asking me earlier about the LADD useage? If so I think I know your region. I used to do some railfanning there in the late 80's and early 90s. Anything interesting in that telemetry? I usually listened to RTC and the talking hotbox detectors.

>>2972749
The same thing if someone spoke on US MIL frequencies.

>>2972830
>Are you the one asking me earlier about the LADD useage?
No, that was another Canadian anon. I think he's in Alberta. I live in BC.

>Anything interesting in that telemetry?
The data is interesting to a rail fan, but extremely boring to a regular person. The DPU transmissions report brake line and cylinder pressure, equalization tank and main reservoir pressure, throttle setting, brake position, tractive effort in lbs, if its motoring or if the reverser is on, if the headlights or sand is on, etc. Its actually a lot of data. The end of train devices report less, mainly brake line pressure at the rear. Head of train devices provide the least amount of data and really just act as a signal of an upcoming train in my case.
When they switched from ATCS to PTC (positive train control), we lost the ability to monitor block and switch activity on the 920mhz freq, so this is all that remains for rail road data that isn't encrypted. All their voice traffic is in the clear still. I can hear 3 hotbox detectors from my QTH, which is nice.

>>2972836
nothing

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>>2972857
>nothing

>>2972906
yeah not scared in the slightest.

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If I wanted to chat with people over radio, would I be better off getting a Ham, Shortwave, or sticking to CB?
I have a CB, but I’d like to extend the range. But if I’m going to do that, idk if it would just be smarter to get another type of radio.

>>2972850
Okay, I was still thinking of the right guy. :-)

Interesting info on the telemetry. A long time ago I lived next to the Laggan sub and used the local hbd to provide early warning of an approaching westbound train. Gave me enough time to run down the street to catch the consist. Although some nights if it was clear I could hear those SD40-2's in notch-8 a long ways off. Back then I was using a 4-ch Radio Shack crystal scanner (cash poor teenager). Worked great, no pager intermod which plagued my 10 ch Pro-31 I purchased 2 years later. Always interesting when the hbd reports an odd number axle count.

>>2972750
That guy died when you were 7 yo.