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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.