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>RF Exposure Calculator
https://hintlink.com/power_density.htm

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>Listen to radio via the interwebs
http://websdr.org/

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breaker 19 this here's the swollen prostate you got your ears on?

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Stand-by, I have to QSY. Comms are being interferred with by the incessant, non-stop digital drone of %&*@! computers slowly texting “599” to each other.

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>still wasting money by buying from the antenna jews

how is activity on some of the other hf freebands? 6600khz, 13790khz.
also, anyone with any experience in the ISM band of 13mhz?

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>local fire
>major damage
>fire still spreading
>ARES activates
>gets in the way just to make themselves seem relevent
I wouldn't be surprised if they started the fire.

>>2987893
where did the ares man touch you anon?

>>2987901
Right in my repeater.

>>2987813
I want a QSL card from H0MER.

What are your preferred news sites for /ham/ news? I used to watch Techminds on YouTube but he seems to have fallen off the net.

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>>2987833

>>2987941
I don't. I got tired of them parroting the same exact stuff as if every single one of them got the same script to read from.

is it worth it saving up for one of the more expensive radios like icom 7300 or something second hand?
i see that they have unlockable vfo. do most other radios have that too?
also, having a built in antenna tuner is very good.
thats just an example

what is the cheapest radio that has built in antenna tuner and unlockable vfo?
i mean using 22m or 45m or 11m + the standard ham bands.

any opinions on xiegu g90?
i see one second hand for 200

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>>2987996
>what is the cheapest radio that has built in antenna tuner and unlockable vfo?

>>2988026
i think xiegu g90 fits the bill.
it also has an swr scan which is handy.
the one for 200 is gone. it was cheap.

could some kind anon post a problem for me, I have with a hermes lite 2 sdr, on the support google group? I managed to never have had such an account and they offer no other option. It would be much appreciated and I offer one or two internets as a thankyou gift.

>>2988093
no

>>2988098
you must be some kind of a popular fellow ..

>>2988101
do shit yourself. no one wants to be the middleman in this thread and another thread.

what a stupid thing to ask.

>>2987996
>what is the cheapest radio that has built in antenna tuner and unlockable vfo?
The cheapest is the one you make yourself. Last thread had some practical links.
>i mean using 22m or 45m or 11m + the standard ham bands.
Those are some unusial bands, what are you planning?

>>2988590
fishing vessels

>Very Lazy Edition: Coil-Shortened Dipole Antenna Calculator
>https://www.66pacific.com/calculators/coil-shortened-dipole-antenna-calculator.aspx
Hey! An edition based upon my post!

Btw, it didn't work. Instead, I just coiled so much on 4in diameter pipe 1ft long (R came out to be around 200), center placed the coil, the tuned at the last part. It's sweet spot is 1.945. Thamks to a tuner, the gentlemen's band is now covered. Even interrupted the only conversation on the band to ask for a signal report: around 55. Lol, as expected.

80m and 40m needs some tuning bit still work with an swr of around 3. 20m is spot on at 1.3.

What would a signal look like if you apply a sine audio into a SSB transmitter?
The immediate answer would be that it looked like a sine shifted up, yet when you key the sighnal on/off, there is a transition. For an AM signal it would go either side of the carrier, but on a SSB it would be to one side only. So for USB it should be on the upper side of the sine signal, right? So for that reason the signal has to be a bit more involved. Anyone got a clue? The ham stackexchange was no help.

>>2989067
maybe they would have been more helpful, if you'd be able to ask a proper question.

>>2989067
Do you know what fourier and inverse fourier transforms look like? Or how sine waves multiply?

If you have a 1kHz audio sine, modulating with a 1MHz carrier via AM, then you'll get a 1MHz sine wave that varies in amplitude at 1kHz, without crossing zero. The envelope will just be a 1kHz sine wave. Because of beat-frequencies. The keying on of this signal will look like two sidebands increasing in volume.
output = (A*sine(1kHz) + C) * B*sine(1MHz) = A*B*sine(1MHz + 1kHz) + A*B*sine(1MHz - 1kHz) + B*C*sine(1MHz)

If you remove the carrier wave so you have AM/double-sideband suppressed-carrier, you'll get a 1MHz sine wave that varies in amplitude at 1kHz crossing zero. The envelope will look like it's full-wave rectified 1kHz sine wave.
output = A*sine(1kHz) * B*sine(1MHz) = A*B*sine(1MHz + 1kHz) + A*B*sine(1MHz - 1kHz)

If you then remove the lower side-band so you just have the upper sideband, you'll be left with a 1.001MHz sine wave. The envelope will be flat, DC. In order to demodulate this, you need to know which frequency it's actually meant to be transmitting on. If you tune your radio to 1.0005MHz instead of 1MHz, you'll hear a 500Hz sine instead of 1kHz.
output = A*B*sine(1MHz + 1kHz)

For any suppressed-carrier AM modulation method, be that single or double-sideband, ideally no power is transmitted when no audio is being modulated. When A=0, output=0. This is one of the motivating factors behind suppressed-carrier transmission, to use less power to get the same signal across. So the keying on of any suppressed-carrier's audio waveform will just look like the sideband(s) rising from zero, not transitioning from any carrier.

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Should you coil this dipole?

>>2989272
>Do you know what fourier and inverse fourier transforms look like?
Yes and yes
>Or how sine waves multiply?
Also yes.

Yet that does not explain what the signal would look like in time domain when you key on/off a sine input to a SSB modulator.

>>2989338
No, I'd rather use existing scaffolding for a full sized dipole:
https://www.goldengate.org/exhibits/facts-and-figures-about-the-bridge/

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>>2989527
>what the signal would look like in time domain
A quickly rising and falling amplitude of a sine wave. Be that at 1khz after being demodulated, or 1.001MHz before being demodulated. Pic related.

>>2989533
It'd be easier to make the bridge an efhw. Hopefully you have a great atu because matching that is going to be a bitch.

just had my first brief and mostly one sided qso on 11m.
some brit cqd on 27.555, said he would monitor 27.485.
i went there and replied.
he could barely hear my call sign but got the division prefix and the numeric part of the callsign.
on receive it was much better though.

i think its because the radio is in dire need of maintenance, probably some caps and alignment but regardless, i'm happy for the semblance of a qso.

tonight i'm constantly hearing uk and ireland. some noticeable propagation is going on.

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It’s time to start judging men by the *girth* of their antenna.
Seriously… what’s in that thing?

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>>2989753

I don't know if any of you /ham/planets use the ATS25, but I do DXing and I'm a lazy, impatient fuck, this shit is pretty good

https://golden-radio.com/

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>>2989755
Interesting. Looks a bit like one of those phased array antennas except with really complex “pads” I tried tracing their PCB design and came up with picrel.

>>2989802
I try not to think about it, the demons can see you if you.think about them.too.mvuh

I am sitting in the dark listening to BPM China because my electricity is out. No hint of Jane Barbe tonight though.

i'm starting to narrow down my choice to the Kenwood TS450(S)

anyone used these or similar models ts690 etc?

>>2989570
The rising and falling parts are the ones that will cause sidebands, and on an upper sideband you will, strangely, get just get a sideband tail to the right on a waterfall diagram. And there is no way a sine wave will be able to do that.
This is a hard question.

>>2989975
The changing amplitude of a sine wave, when you take the fourier transform of it, will look like a collection of harmonics alongside the sine's main frequency spike. That's just how fourier transforms, and hence waterfalls, work. The slower the transition, the less significant those harmonics will look. With a really fast transition (significantly faster than the rise on an equivalent constant-amplitude sine), you get a bunch of higher harmonics going off by something like 20dB/dec. The fourier transform of a step response. With a slow transition, you'll get splitting of your 1.001MHz sine into miniature side-band-like things, and the slower the transition the closer these are together.

Would be fairly easy to do in python or matlab or whatever, just generate a sine wave multiplied by some sort of keying function (e.g. atan(w*(t-t0))/pi + 0.5 ), and FFT it. You may want to add a windowing function if the beginning and end don't line up.

finally after 2 (two) months of monitoring the vhf repeaters by the 3-3 rule i heared two boomers talk
something happened, vhf is not dead

>>2990037
>Would be fairly easy to do in python or matlab or whatever
OK, please do.
Say, a 1 kHz audio modulated to upper sudeband at 10 MHz, with a sinc shaped keying on/off, and then show the time domain signal.

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>>2989722
Nice. For a while when I first got on HF I could hear decently but couldn't be heard well. Turned out I needed a groundplane for my vertical I was using. After that it was much better.

>>2989838
>skree... skree... skree... skree..
I spent friday night out in the boonies monitoring WxFax transmissions out of Alaska, Hawaii, and California plus some NAVTEX. Also a bit of listening to VLF and LF beacons and some AM BCB monitoring. Clear night, good conditions on the bands while nursing some beers with my Coleman lantern hissing away. Comfy.

>>2989956
Yes. I bought my TS-690S new in '93. I still have it and it's still my No.1 favourite radio in my small collection. I've also played with a TS-850S and a TS-440S to a limited extent.

>>2990124
i'm using a horizontally pol. full wave loop. dont think it needs a ground plane

>>2990127
i see these going for 400-500 usd. they look interesting. with vox, it would be easier to do digimodes and 100w is perfect for most uses.

>>2990201
They're pretty decent radios and still hold their own today. If you do voice work, they're legendary for their audio. Unless you get an abused unit, I don't think you'll regret owning one.

But they are getting up there in age so look out for leaking capacitors and the back-up battery. Not that it's common, but it does happen. Otherwise there are 2 weaknesses to be aware of. It's recommended that if C104 on the IF board is original (brown case) to change it out with a 25 V one, preferably with a Panasonic brand. They say if it hasn't leaked yet, it will. The originals are rated at 10 V but often get spiked at 14 V. It's easy to access so no fears about a complete radio tear-down. Flip the radio over and open the access panel, the capacitor is right there near the filter slots.

The other thing to be aware of is that it uses proprietary DDS chips. The early chips were the 6631's and the later 66312's. The 6631's supposedly had a flaw and were prone to failure yet I don't know any 450S/690S owners that experienced that. My radio has the early DDS chips. Up to a few years ago you had to find a parts donor if you needed to replace it. I stumbled on a local parting a TS450S and I snagged the DDS board for cheap just in case. Regardless, there is an outfit in Italy called RF Systems that sells aftermarket boards.

I did RTTY and PSK31 with mine. I recommend getting the CW filters for both IF's for narrow-band digital work. Inrad's if you can afford them. And finally, but not lastly, you can do computer control relatively easy if you are into that. I never did so I have no insight into that.

Hope this helps.

>>2990308
thanks for the tips, yeah i kind of expect to change a few caps in older electronics.
in around 1990, the battery backed memory was pretty common in all kinds of electronics.
i had to change the cr2033 on two synthesizers before.
caps are no problem either.
the worst problem would be that special chip youre referring to

>>2990308?
did you have to align it?

>>2990382
I've never done one to it yet. I lack a signal generator but am on the lookout for one. I'm also thinking about getting an aftermarket TCXO for it.

Hey guys, any ideas on how to use LoRa tech to help out campers near a national park? I read you could set up a "wifi" access point where people could send basic text messages that can bounce all the way to the city. Seems neat.

>>2987813
Bump

>>2990900
Can be done with a system like Meshtastic or Rnodes. But each user needs a LoRa terminal of their own. The common method is for the LoRa terminal to Bluetooth to your phone, and the app on your phone is used for interfacing with it to send and receive messages. But I believe you can also buy standalone terminals. A stand-alone terminal at each tramping hut might be sensible, assuming there isn’t already a method for emergency communication there. Lending terminals to trampers might be feasible, they come out to something in the ballpark of $20-40 for a Bluetooth model. Heltec and Lilygo make decent ones IIRC.

LoRa terminals have decent range, but the real power is in their ability to hop from node to node. To properly take advantage of this you’d either need lots of spread out people with these at any time, or to set up repeater nodes, probably with solar and batteries, atop nearby hills.

And then at the receiving end, back in civilisation, you’d need to figure out what to do with the messages. It’s not like they’re SMS texts sent via a SIM. Maybe you turn them into emails, or just use them for emergency comms.

>>2991101
don't bump here, this thread will be around for months... unfortunately.

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>Meshtastic

>>2991164
What's wrong about it :(

>>2991180
Nothing, actually. I like it along with the concept. I'm just making fun of the initial sojak reaction many had to it before it really took off.

>>2991127
as much as i find meshnetworks cool and useful, their usability would go up 10 fold if the used hf frequencies.

imagine a meshnet around 20 metres or even 40m.

even on 11m! despite the patchy and random propagation it would still be better for mesh nets than uhf or more

i understand meshtastic guys dont want big antennas but mesh on hf people dont care obviously.
feels like hf is underrated among the younger crowd.

>>2991127
i also read that hf is used for commercial fishing boat mesh nets and that some such nets exist happily outside of public knowledge
in general, i've seen references to hf mesh in engineering articles about industrial mesh network use.
uhf honestly looks like a toy in when comparing reliability

So I'm thinking about setting up a solar/battery powered FM radio station. A clandestine setup. A disposable one. I figure I'd be running around 1 watt so the costs of assembling everything won't be insane since I can't predict how long it's going to last. But that means I need to scout the perfect location. There is some mountainous terrain that's remote in my area that would be perfect to transmit from with a yagi but I'm not so sure 1 watt is enough for the kind of distance it would be from the town proper. I bet I'd fucking kill with 10 watts though going by my own observations of translator stations in the US that used that kind of power. Also that introduces other tradeoffs. I can get it up to a site where it is going to be hard for other humans to get up there and tamper with my shit but it also means I can't just walk up near the transmitter and access a hidden wifi access point to update the files on my audio source.

Just a bunch of ideas but eventually when I have money to flush down the toilet I'll try to actually do this.

>>2991308
>>2991309
I suspect multipath propagation could cause even a single chirp-spread-spectrum signal to overlap itself and become incoherent. LoRa itself eats up tens of kHz bandwidth, not a big deal at 70cm but might not be welcome on 40m. And there isn't really a good way of controlling range, you might be trying to talk to a node 150km away, but you get a lucky bounce and happen to overlap with someone else's transmission in japan. Chirp-spread-spectrum is bad for coincident signals, neither of the original two signals can be extracted from the resultant overlapping RF from what I've read, at least if they're at the same frequency and spread factor. Hence the dead-time in the LoRa standard.

>>2991318
You can try to calculate your link budget to see what kind of signal you'd get. 1W continuous is doable, a 7.2Ah UPS battery has 86Wh of energy stored and would nominally last you 86h with no charging. I'd avoid such an extreme discharge of such a battery, but an 18-38 Ah lead-acid, or 12-26 Ah lithium would probably suit you fine with a ~15-30W solar panel, and appropriate charge controller. I figure you should be able to manage the power side of things in under 100USD, cheaper if you can use salvaged batteries (car or laptop or scooter). No clue about the transmitter, if there isn't anything off the shelf I'd attempt to use a cheap automotive FM transmitter, solder coax inside it, and feed that to a cheap aliexpress RF amplifier.

If anything, it might be easier to make it an FM repeater, and beam audio at it with a highly directional antenna from somewhere more accessible. Having a wifi access point or whatever would be another thing to eat power.

>>2991320
Well for the audio source I was thinking of using a Raspberry Pi Zero W. I can preprocess my audio and have the Pi acting as an AP I can connect to. Also I can have a script running that controls what's playing so there's some logic to my programming and it doesn't sound like some guy set up Winamp and turned on both shuffle and repeat all which is basically what every other pirate station I've ever encountered sounds like.

I've explored lots of STL concepts in the past. From looking into the ways the pirates in London do it to the professional setups in the country where I live that I found with my SDRs. I guess that makes the most sense if I was going to go all out with the mountain site idea but I think it would increase the budget. Even if I could get much better results passing through MPX generated by gear in my house than aliexpress crap shoved into a box I'm not afraid to lose.

>>2991321
>a Raspberry Pi Zero W
That will eat more watts than a cheap MP3 player or MP3 playback module, but it might be worth it for the extra features.

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>>2991323
Well it will be running headless and I can probably do a lot to get the load down. Start with a minimal distro and further debloat it. Everything can be managed carefully.

>>2991180
NTA but for inexplicale reasons, mestastic is a bit cliched. I guess it will be hot the day it becomes prt of every mobile phone. Phone makes sure need something more distinguishing features than the sameness they have now.

>>2991308
>as much as i find meshnetworks cool and useful, their usability would go up 10 fold if the used hf frequencies.
Can ISM bands be used? There is one on 13.56 MHz. Also check out
https://www.lwca.net/sitepage/part15/index-what.htm

>>2991318
>So I'm thinking about setting up a solar/battery powered FM radio station.
Bu why??

>>2991331
I've always been interested in FM broadcasting so I'd like to mess around with it.

>>2991324
More recent Pies(like 2040 and newer versions) may be better, that diagram must be super old. ESP chips are even more power efficient.

>>2991333
At least with meshtastic it would be legal and provide more enjoyment for more people.

>>2991345
I might mess around with some legal stuff later too but I live in a rural area where there would be few other people interested in that. That's part of the reason why FM piracy seems like it could be a bit of fun. At this point there are basically zero stations that provide a reliable signal to my town. There were some before but they have since shut down. The terrain that surrounds the area makes it hard for signals from the closest cities with proper stations to make it in. TV is a different story with mountaintop sites serving us as well as the now gone FM ones used to.

>>2991346
>At this point there are basically zero stations that provide a reliable signal to my town.
Damn. I guess that if you build a repeater nearby and broadcast comfy music or podcast, no one would bat an eye. Just don't yell NIGGER 24/7, and I think your neighbours will appreciate you providing an FM station. Also, plan something in case of emergencies, your repeater could save lives.

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welp i guess i'm going to now get into HF
I picked up a yaesu something 100w for 20 meter for a decent price.
How much will this thing fuck up other stuff, and how much will it get fucked up by other stuff?
I have a mountain top stub tower that already has power and network, and also has some meshshit. It's a DC site, but obviously has a solar charge controller, just no inverters no AC.
the tower is kinda full so I was going to go about 40ft away and put up a mast just for it for a full size half wave dipole and just run a coax over to the main cabinet and cram the radio there. Or should I move it further and just run power and network to a new cabinet for the radio?

>>2991345
>More recent Pies(like 2040 and newer versions) may be better
The RP2040 and its sucessor are microcontrollers, not SBCs. Same for the ESP32. Entirely different category of device with different use-cases.
Now this anon may not need an SBC, depending on how the station needs to be run, but running a full linux distro with known good utils is probably a lot more flexible and reliable than programming your own code to run music to an FM transmitter. An MP3 player would be more reliable but even less flexible.

>At least with meshtastic it would be legal and provide more enjoyment for more people
Meshtastic cannot broadcast audio, full-stop. Maybe you can get 60kb/s bit rate out of LoRa, with continuous transmission (not allowed by LoRa), and even then you'd be getting worse than AM radio quality.
Plus low-power FM is a thing, where I live you don't need a license for it at all, just to remain below the 1W power limit and broadcast your station name and contact details at least once per hour.

>>2991451
>Maybe you can get 60kb/s bit rate out of LoRa, with continuous transmission (not allowed by LoRa), and even then you'd be getting worse than AM radio quality.
At that kind of bitrate with modern codecs I could probably manage to put out audio, in stereo even, that sounds more pleasant than what most people hear on AM these days. That's not AM's fault at all. It's more down to how shitty most AM radios produced in the last 30 years are. Whenever I'm picked up by some ride service driver in the city and their Toyota has an AM talk station on it sounds like complete ass due to the filter width being too narrow. Meanwhile I hoarded Sony ICF-P36 units when they were finally discontinued because I like how it sounds on AM.

That's not to mention all the electrical interference etc on the AM band that makes listening a shitty experience. But transmitting audio on LoRa would mean people would need specialized equipment to pick it up. Perhaps things like this are an interesting idea to explore but it would require hobbyists to come up with tooling and standardize it.

>>2991453
Ok with compression you can get kinda crusty sounding MP3 at 64kbps, which is close to the 62.5kbps maximum bitrate of LoRa, definitely better than AM, but again LoRa is designed for short packet bursts with lots of dead time, allowing others to use the band when you're not transmitting. Unless you had an agreement that nobody would need to use a band of LoRa in a certain area, it would be a hard sell. Also that maximum bitrate means minimum range and maximum power consumption. You could maybe use it for short crusty voice messages if you really wanted.

That said, there definitely is room for a low-power digital broadcast audio protocol to exist. Room for lots of Chirp Spread Spectrum and similar stuff, really. It's pretty cool technology. I imagine you can do something similar by using a sinusoidally varying frequency, and shifting its phase, though ramping chirps would likely be easier to demodulate.

>>2991454
We have much better options than mp3 these days. Even a long time ago we had mp3pro. Digital Radio Mondiale uses xHE-AAC to achieve decent sound with very low bitrates but I believe it's heavily patent encumbered so opus is a better choice.

>>2991455
Oh yeah, Opus goes to 6kbps for VHF radio bandwidth encoding. That might be doable for voicemails or short calls. But at 3-4000Hz it's recommending 15kbps for mono music. Interesting tech, this kind of audio compression is probably when you'd want a proper SBC instead of a dinky microcontroller.

>>2991456
This is kinda making the wheels in my head start to turn. Could you imagine if an extremely efficient modulation scheme with a high degree of error correction existed that was open and patent/royalty free? To me DRM doesn't really seem to be good enough. Like if I have a marginal signal there's all kinds of dropouts etc. But if streams with these kinds of bitrates could be transmitted using less bandwidth and more error resilience it could be a big deal for pirates, or even legit broadcasters.

>>2991475
Seems to be alive where I live. I listen to the guys sometimes but it's not really my thing.

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I own so many radios at this point but I always find myself using the ATS Mini now. The form factor really helps with portability. Even though the tiny speaker sucks it's enough to fill a hotel room up with sound which helps while I'm working. I find the controls frustrating to use but I see there's now an Android app to control it over Bluetooth. Every time I look in the groups on Facebook there's some kind of new feature they came up for these things. I'd gladly pay more for a better radio that's of a similar size but also open source. Something with a TEF6686 would be really appealing for me since I mostly listen to FM.

>>2991499
what you hear is the death rattle of a hobby.

>>2991505
It ain't over til it's over

>>2991502
>Every time I look in the groups on Facebook there's some kind of new feature they came up for these things.
Such as? Sounds interesting

>>2991475
Ham radio is far from it due to larpers adopting it, and telling others comms need to be in their shtf plan.

>>2991475
radio is like water now. except more expensive.
no going back to pigeons unless absolutely necessary (pretty much never)
internet is for plebs and they are locking it down.
internet service providers have their own oligopolies in most countries

>>2991669
more:
the only way forward is further radio adoption. bands will have to be recycled, sometimes even organically, like has already happened before many times. also more digimodes and mesh nets on hf are needed. the present will be our future and the future will be our past.

>>2991669
>internet is for plebs and they are locking it down.
what are jammers?

>>2991689
Who would genuinely make the effort to jam radio signals in an emergency? They can be tracked too, btw.

>>2991689
It is hard to jam signals you cannot find.

is it a good idea to buy a used yasu ft-100d or icom 706mkiig as a newfag ?

>>2991769
what is the government? or some other nefarious actor.

>>2991851
what is very wide band jamming?

>>2991951
aka cutting off your nose to spite your face

>>2991951
A waste of energy.
You have a limited power budget to divide across a certain bandwidth. Narrow band with high power/Hz or wide band with low power/Hz. This is what allows Morse code operators to burn through jamming.

>>2992155
>limited power budget
government

>>2992156
Unless you plan to put the air on fire you will have to limit your output. And back in the day when I worked for Nintendo, I was on the receiving end of a .mil jammer. These tend not to be powered by their own nuclear reactors.

>>2992158
Speaking of turning the air on fire,
My buddy had a laser power meter instead showing OL or something it says 100 DB

>remade transmission line to eliminate cuts.
>cut 150 ohm balanced line at approximately half wavelength multiple (double coax)
>compare signal strength by switching wire (antenna is similar to delta loop and is balanced) to see which side of the loop is fed best by the "+" output on the radio.
>no balun, no ground (except the paired coax shield on the feedline)

today had a short qso and got graded 5 by 5 on 11m with particularly good propagation in western europe benelux/france/london.

>>2992255
what i found interesting is that ground (normal house outlet ground) in my particular setup reduces tx strength as measured by a handheld radio in close vicinity at about a meter above ground

i've read that some radio setups hooked up to balanced lines and antennas can work better isolated from ground altogether because ground basically makes one line have a slightly different impedance.

note that i'm talking about setups with no balun

any thoughts?

>>2992255
>>2992260
same person, sorry for the spam

I don't remember why I saved this article, but I am tempted to build a faraday cage and test to see how much of it is true: https://www.nytimes.com/1925/08/21/archives/says-human-brain-emits-radio-waves-prof-cazzamali-of-milan-declares.html

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>>2992255
cont.

today i removed the last bit of unbalanced line in the feedline and decided to test txing FT8 on 11m using an android phone with FT8CN (no google services required).

this is what came up on psk reporter. i did this for a few hours back and forth mostly sending CQ calls and replying whenever anyone called back.
completing the whole QSO proved tricky many times as propagation is not exactly stable. its strong but its not stable.
but anyways, on pskreporter it seems like i was heard in most of europe.
the antenna is horizontally polarized delta loop fed through the apex which points down. since it is directional, it is positioned to radiate mostly towards about 40 degrees and 220 degrees and the radiating part is at about 12m above ground.

pskreporter is really nice. will now do daily checks to track propagation.
it sort of validates the radio setup but also it validates FT8, it seems to work even on really old radios like this. this president grant is as far as i know in original state and and i dont know when caps were changed if ever and it does not seems aligned very much either.

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>>2992399
Imagine the length of the dipole to resonate with this. Better off just using a EFHW on a 49:1 unun.

>>2992399
>>2992491
Makes you wonder what happens if you take the brain waves of one person and amplify them and pipe them into antennas around their own brain, or another person's brain. Imagine setting up a feedback loop between two people. Or just outputting a specific frequency at high power to put yourself into a certain state of mind, though you'd probably want to match the phase and frequency of whatever wave is already present, instead of just adding a 7Hz wave atop your brain's existing 5Hz.

I guess it's in the electric-field? Radiating a few watts from capacitive plates on either side of your head might get pretty high voltage. Seems like a good way to cause epilepsy.

>>2992399
I visited a lab once where they did magnetoencephalography using a SQUID. No magnetic materials were permitted anywhere near the building, lots of nails and screws had to be removed. For the shielding they used >2 cm thick super pure Al sheets specially ordered from a plant using a freshly servied electrolysis cell.
So it is not impossible but I will be deeply impressed if you succeed doing this.

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>Read about DXing
>Oh, that sounds really cool, my dad does that
>I should get a ham radio
>Start studying for technician license
>First question: "Which of the following results from the fact that signals propagated by the ionosphere are elliptically polarized?"
Um....I just want to fiddle with a radio. Why is this considered basic knowledge required....

>>2992677
It's ancient gatekeeping shit. Do what 90% of others do and just memorize the questions and answers.

>>2992677
just do it or even start on 11m, learn as you go along, no license needed, also there are "gray zone" bands if you know where to look

>>2992677
that said, i'm unlicensed and all knowledge whether about ionosphere or transmissions lines did help me get to the point where i could get out on 11m and make some contacts both on ssb voice and ft8. its not perfect but its better than when i started 6 months ago

i mostly look at muf charts as a secondary way to check what to expect.
my primary way right now is to send out some ft8 cq calls and check pskreporter and monitoring 27.555 mhz.

why i think actually getting on air is more important than say just looking at muf is because right now, my area is at muf 19 mhz to 20 mhz, however, i was able to get out twice on 27 mhz to germany about 1200 km, once to uk also about 1200 km and once to another region in france about 450 km
but that does not mean completing an actual qso even on ft8. it just means i was heard and my call sign and maidenhead coordinates were heard.

basically
if your antenna is placed at a specific position for a specific take off angle and you work on all the problems you may encounter such as transmission line, ground issues, then you might get out anyway at least with ft8 even if you are above MUF.

>>2992677
unless you want to talk to boring people you do not need a license to "fiddle" with a radio.

>>2993497
I love radios and have the highest license level available to me, but I have learned that its best to avoid ham radio ops whenever possible. Most of them are the most boring people imaginable to speak with. Plus they're typically old retired guys so I have nothing in common with them.

Oh, you run a 5 el Yagi and an IC7300... how interesting. And you say the wx is cldy? Well shit, I cpy 5x5. Tell me about that toe of yours with gout.

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>>2992455
the last week from my location has been spotty. was able to get out to at least one station on a distance of 1000km in about 10 cq calls repeated twice per day. often2 to 3 stations per day, sometimes 5.
number of monitors on pskreporter varies also between week and weekends so this affects reports too

just now picrelated.
propagation seems ok on both voice and ft8.
it seems like the average distance hovers at 1000km.

the current 3000km muf is about 17 mhz

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>>2993602
this is the top of the antenna

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>>2993603
rotated.

looks like the steel bars in the railing are coexisting with the antenna.
since the radiating part is at the top and its horizontal, and the bars are vertical steel bars, that probably helps because of polarization difference

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>>2993604
the adjustor can be used to tweak the swr.
however, my transmission line is a 150 ohm paired coax line (75+75) and it is cut at half wavelength multiple and so, its a monoband transmission line. also it should at least in theory be balanced

adjusting the effective loop length was best done when radio was hooked up close to the antenna with almost no line in between.
later, the 150 ohm line was cut to adapt to that specific resonance.
as an inconvenience, any change in loop length must be accompanied with a corresponding transmission line length adjustment so i just leave it in one place.
lowest swr reading is around 27.555 about 1.2 but 27.265mhz also works well for txing ft8 with swr around 1.5

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>>2993605
this setup is in the middle of a city and rf noise is pretty strong.
this is why 2x catv coax was chosen.
the only place where the transmission line could be pulled was by crossing other cables which may or may not be radiating noise.

its not clearly visible from that angle but from the window the transmission line is attached onto a green conduit out of pvc (from recycled hoola hoop) to get some distance from the random cables attached to the wall. i didnt determine yet if it helps or not

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>>2993606
and finally, this is the beginning of the line plugged straight into the radio no balun or choke

the shields are connected together at both ends of the line and the radio end is connected to mains ground.

the radio itself is not connected to ground because the antenna is symmetric and the transmission line is balanced.
tx signal strength was tested to be better without it anyway.

total cost was at about 100 euros (radio, catv coax line)
antenna wire is from standard braided mains wire

how come in one of my cars anytime I push the mic button on my CB the rear speakers freak the fuck out
is it because I have the slack antenna wire coiled next to one of em
also why in my other car does the CB freak out whwn I park next to a cinderblock wall

>>2993607
what the fuck man buy some cheap PL connectors

>>2993607
Congrats, anon, on one of the most MacGuyvered stations i've seen. :^) And I mean that in a good way as pskreporter shows you are getting out in a less-than ideal location and that's what counts. It reminds me of those clandestine radio stations that were used in occupied France during WW2.

I too am plagued with RF noise from the urban environment. Filters and audio DSP's help.

It looks like you have a vertically polarized loop. They tend to be directional and can be good for nulling out interference and directing your signal in a particular direction. Have you thought about trying a horizonal loop pinned to the ceiling? It'd be even better if you could get it outside and above the roof but I understand if you have limitations to that.

Otherwise, tuning the loop at its feedpoint then connecting the feedline and tuning that is sound practice. I recognize the amount of effort to do that. Your SWR's look good.

>>2993745
>Congrats
thanks!

i'm pretty sure the antenna is horizontally polarized.
i checked with eznec and a handheld.
i followed the guide from practicalantennas for full wave loops. its about 37 degree angle at the feed point for 50 ohm.
also, i have very few local contacts. almost exclusively long range.

>>2993606
Thoses LED strings might emit a lot of RF. Have you checked conditions when these are turned off?

>>2993879
yep i checked that. the leds are programmed to turn on/off between day and night and only for a few hours. they are not mine and personally i wouldn't use them at all but thats how it is.
i havent noticed any difference.

using a handheld i localized another source which might be the hvac system and that is harder to remedy.

there is another probable source and that is those digital electricity usage counters, there are about 10 of those not far from the antenna.

after noticing the new source i basically took the leap towards doubled catv coax.
its cheap and has about 60 db isolation.
except moving, i dont see what else i can do here

>>2993879
another thing is the gutter which is horizontal and paralel to the top portion of the antenna. i need to see if the gutter emits anything by picking it up somewhere else

correction: i need to see if the gutter emits anything by *relaying noise* from somewhere else
>>2993920

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>>2993856
>delta loops
Ah you're right, they are horizontally polarized. I know nothing about them, hence my ignorance. I had to spend some time reading that site.

I really need to try and sneak a 50 MHz beam on the roof of my apartment building. It's after midnight here local time (07:40Z) and we just had a brief tenuous path open up to Japan.

>>2993932
i really like delta loops, you can play around with vertical/horizontal polarization by moving feed point and you easily adjust for impedance and swr

>>2993932
and nice picrelated.
50 mhz? how is that? how often do you get to get out like that?

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Hard to get a good pic of the wires themselves, but the 40/20 fan dipole is up 30'.

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Might pick up an ftdx3000 from a local OM if I get the right price. Has an IF out so can use a SDR dongle for waterfall. Testing it at the sellers place next week. It has superior cw roofing filters than my current rig.... Hope it works out.

>>2994526
I own an ftdx3000 and I consider it to be one of the best radios out there. It still punches with the new flagship radios like the 101d in many ways.

>>2994526
>ftdx3000
>>2994526
>Has an IF out so can use a SDR dongle for waterfall.
But it already has one ?
Although, not gonna lie, this looks extremely comfortable to use
https://www.youtube.com/watch?v=bSJUdfRR9gw

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ft8 on 11m feels like a chat room here in europe yesterday and today

Is it possible to build ultracheap headless lora nodes using just an esp32 and a cheap compatible antenna/chip if it exists.
Seems interesting to just order a bunch and solder them together as "throwaway/giveaway nodes".

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about 17 ft8 qsos one of which with lebanon
218 24-hour reports on pskreporter

i have to manually activate PTT each time since radio has no VOX adapter.

in general, lucky with the propagation today. good day.

>>2994526
>panadapter
I do that with my Icom R7000 VHF/UHF/SHF receivers. It can be handy at times.