Extra Very Lazy Edition: Previous Thread: >>2987813>New to /ham/? Read this shit!http://www.arrl.org/what-is-ham-radiohttps://www.fcc.gov/wireless/bureau-divisions/mobility-division/amateur-radio-service>Your search engine of choice works well too!>The archived wikihttps://archive.is/PjR5s>NEW FAQ is updated to preview 15https://files.catbox.moe/aftx43.htm>Coil-Shortened Dipole Antenna Calculatorhttps://www.66pacific.com/calculators/coil-shortened-dipole-antenna-calculator.aspx>Idiot's Guide to Coax Cablehttps://www.pcs-electronics.com/guide_coax.php>Looking for frequencies to monitor near you?http://www.radioreference.com>Random Wireshttps://udel.edu/~mm/ham/randomWire/>Basic Rx loop fundamentalshttps://www.w8ji.com/magnetic_receiving_loops.htm>DIY SWL Mag. Loophttp://www.kr1st.com/swlloop.htm>Small Tx Loophttp://webclass.org/k5ijb/antennas/Small-magnetic-loops.htm>In Depth Loop articleshttp://www.kk5jy.net/magloop/>Homebrew RF Circuitshttps://www.qsl.net/va3iul/Homebrew_RF_Circuit_Design_Ideas/Homebrew_RF_Circuit_Design_Ideas.htm>NEW Libraryhttps://mega.nz/file/UCgEGAjb#rwNcnMAQCUUbSp8supsFvn9QEHCWUW86eLcZa16ZG4Y>Online Practice Tests:http://aa9pw.com/https://hamstudy.org/https://hamexam.org/> Real-Time Propagation Datahttp://prop.kc2g.com/https://www.ham-stream.com/>Space Weatherhttps://www.swpc.noaa.gov/communities/radio-communicationshttps://www.solarham.com/>point to point predictions, its free and will give you an idea of how much power/ what frequencies to use to reliably talk to your friendhttps://www.voacap.com/hf/>WSJT-X Home Pagehttps://wsjt.sourceforge.io/wsjtx.html>Homosexual (ft8) guidehttps://www.g4ifb.com/FT8_Hinson_tips_for_HF_DXers.pdf>APRShttp://www.aprs.org/>Weather Fax resourceshttps://www.weather.gov/media/marine/rfax.pdfhttps://weatherfax.com/stations/>how do I into Morse code in a good way?https://pastebin.com/HByjfN4F>Shortwave radio schedulehttps://shortwave.live/
>>3005918
>another thread later>still giving money to the antenna jews
>>3005923When I worked at a railroad I bought a Baofeng and programmed it because I was tired of always lending my work radio out to other people and never getting it back.
>300+ dead, thousands missing from tbe recent deluge. We need supplies badly in N->CQ POTA CQ POTA
how viable are solar+battery powered only wifi repeaters and other types? how illegal would it be to construct a tower in the middle of nowhere hill just above the treeline?i live surrounded by hills from all sides
>>3005923missing the very first square:are you a redditor: yes -> look smugly at this chart and chuckle to yourself about how clever and witty it is
>>3005981Towers are pretty heavily regulated. If it's high enough a plane could crash into it, it needs actual engineering plans on file with the FCC, among other requirements.>>3005986Sounds like you should study it a little closer.
first time into australia on any band ft8 on 40mshould we expect a signal boost in winter time here in europe for dx and by how much if so?it must be the antenna height because everything else is pretty much a compromise.its covered by a roof, its bent, there are plenty of metal objects around, another building on the other side of the wall and in the middle of a city with plenty of qrm.i've noticed on some bands that i tend to transmit a little bit better than receiving but that really depends on band and noise level. everything is far from ideal but at least the height is about 12 m up.i'm also getting out on voice up to about 600 km but the signal is weak with only 20w considering all the qrm everyone has it may be wiser to do 100w instead but then i would mess with my neighbors electronics much more. such is life i suppose. can't have everything. but ft8 and js8 is more than enough for pretty reliable comms.
73's swollen ostrich!
>>3005923I do what I want.
>>3005981There is a slow but steady stream of such repeaters being discovered and taken down.
>>3006146How would you make a fully legally compliant wifi repeater? Is there some sort of automatic power reduction firmware to not interfere with other comms?
>>3006148First get permission from the land owner fo ruse of the land and the use of a tiny shack. Then get the local /ham/ society into the project for the legal stuff. Make sure the shack looks uninviting, e.g. make it look agricultural related and spread manure around the place.
>so many natural disasters and crises>so many ARES members getting in the way just to make themselves feel relevant
>>3006148more of a combination of two point-to-point links
>>3006149A shack? I was thinking just strapping a waterproof 20L box to a tree. On your own property. But I don’t really know how big it would need to be.
the chad scanner.
>>3006168It's be funny if this actually worked.
>>3006164You will need - a pair of transceivers - a rather voluminous filter to get the relay to work at all - cabling, should not be underestimated, along with the tendency to turn into a rat's nest. - batteries that will withstand a few days without sunshine - charge controllers / BMS - solar panels with supports that will survive strong winds - optionally a small wind turbine - a computer/controller to monitor and control the system along with sensors (temperature, humidity...) - fuse box - optionally a small camera - attachments for antennas that will survive strong winds
>>3006266it does work. though I since got proper cabling. but I don't actually use 3 at once.
i'd use some help identifying what seems to be an antenna.found a roll of wire of unknown length but estimated at around 40 or 60 meter. more like 40.it has two wires. one looks thicker than the other.on one end there is an unidentified 5-pin connector. the pins are laid out like a U.two of the wires go to one wire and two others opposite to the first two go to the other wire.the 5th wire in between and offset seems to go nowhere.at the other end of the wires is a sort of shorting device with a pair of joined pins. one pin is thicker than the other just like the wires.with these pins inserted into the shorting terminal, they connect the two wires.the color is darker green, looks like military gear. nice plastic on the roll, hard but with very slight flex if bent but looks like good quality.i'm thinking its some wire antenna or a part of a bigger antenna setup maybe dipole with one leg missing.anyways i put it up as a horizontal loop with many parts which sag because i could not fit it otherwise. its connected to a fan dipole and i seem to get better gain on 40m. however conditions seem to be pretty good right now so i need to test it with worse conditions.any ideas?
>>3006507Photos or drawings.
>buy my first shortwave radio>start fiddling with knobs and buttons >morse code>sermons>weird sci-fi bullshit noises>cubans>conspiracy bent news>house music>alternative medicine>whiskey tango foxtrot>good ol boys talking about tractors, concrete and their radio specs>fishing spots>blues music>bunch of news from mexico, western africa, turkey, china, romania and spain>your standard 4 white dude roundtable podcast about nothing in particular
>>3006797Nice. Out of all that, what's your favourite?
>>3006834Good ol boys by a country mile. Just honest casual salt of the earth boomer chit chat. Finding random music broadcasts is also pretty exciting even if it's just muffled fuzz garbage. Might sample some of the sci-fi bullshit at a later date.
Anyone ever hear of UFO Joe? Dude likes his banjo.
So is WRMI the go to for regular shows and decent signal strength in North America?
You will never be a true ham radio operator until you make a dipole that is resonate on the 2200m band.
>>3006848Always a bonus when you find the right music. Condx are good for me tonight. I've been trying to hear an Aussie LF station but instead I discovered a classic rock station on the AM BCB located in Juneau, Alaska coming in crystal clear. A rare find for me.>>3006884Probably. I believe they are the only SW broadcaster on conus.I wish I could hear Channel-292 where i'm at.
Another R-390 up for sale around here, I am considering pulling the trigger. Anyone here got one or got experience with one?
last week i realized the potential of loops.namely 2x wavelength loop.but how would you fit a 2x loop for 40m in your attic? by zig-zaging the wire. so basically, a 40m antenna with a lower take off angle (due to having more pronounced lobes due to being 2x wavelength) and the zig-zaging does not seem to be much of a problem considering the angle and the otherwise low height for a 1x loop.so with loops, if you dont have the height, it makes sense to make it twice as much in circumference.according to nec simu, you would need more wire though. (about 30% more wire)
>>3007470and the size of this thing is pretty much half the size of a full 80m loop. size is obviously the main deal-breaker when it comes to antennas and this seems to solve that.i'm planning to put it at about 12m height inside an attic and the width of any side can not be longer than about 10m. will test as soon as i get the speaker wire shipment.
>>3007470sorry i was not clear.basically instead of struggling with space to put a 80m loop to operate on 40m (double wavelength loop for 40m)you zig-zag the elements and reduce the sides by about 50%. the zig-zagging is vertical and i only tested a 90degree angle bends for the zig-zag. (like a bunch of rectangles)you could probably make the zig-zags like a bunch of triangles but then the loop would need to be bigger but i didn't model this.double wavelength loops are described on multiple sites as well as zig-zag antennas so this just combines both to make a compact antenna.
>>3007470I know a couple of guys who use full-wave loops but not doubles. If you experiment with this you gotta report back because i'm curious about the results.>>3007436I have a personal rule where I won't buy anything old I can't fix. Because chances are there isn't anyone close who can restore it. Those things are big and heavy thus expensive to ship. I've read how to align it and it's quite an elaborate procedure. The good thing is there is plenty of documentation online so no shortage of info. That said, if the price was right (cheap), and it's in excellent shape... you'd have a classic radio. Now if it was an R-389 i'd be seriously tempted.
>>3006916Another night of great conditions if you were on the Pacific rim. Spent time between 06:00 - 10:00 UTC checking the LF/VLF bands searching for some elusive stations. Heard beacon "ALJ" loud and clear with S3 signals on 233 kHz. Looked it up assuming it to be a local and was surprised to see this is a 50 watt beacon out of Australia 12,753 km away! The beacon was way louder than the 100 watt & 500 watt beacons in my region by a wide margin. I think this is my best NDB DX catch to date.
>>3007476still waiting for speaker wire here.in general, i find 2x (or more) wavelength antennas very interesting because they give you lobes and nulls and the higher in frequency you go on the same antenna, the more dramatic this effect becomes.also, feels like receive is less noisy at double the fundamental frequency assuming antenna is fit for whatever fundamental frequency that happens to be.i've put up a few wire antennas and i noticed that i had a lot of noise on antennas on the frequency they were cut for.( say 20m dipole for 20m)then i read a faceberg post that suggested using 2x wavelength loop to also reduce noise.
>>3007476>I have a personal rule where I won't buy anything old I can't fix.I agree and I have a lot of investment in equipment in front of me.>Because chances are there isn't anyone close who can restore it.Also true. This model seems to be in need of some adjustments, the seller is a little vague, so there is a risk.>Those things are big and heavy thus expensive to ship.About 40 kg, yes. In this case it is within reasonable driving range.>I've read how to align it and it's quite an elaborate procedure. The good thing is there is plenty of documentation online so no shortage of info.In my experience, when people make things seem easy it does not mean what they do is easy, just that they are highly experienced. I have collected a lot of info but the task is demanding. It looks like they let watchmakers in on the project. It is strange they didn't make a R-390B with servo control or stepper motors rather than all that mechanics. >That said, if the price was right (cheap), and it's in excellent shape... you'd have a classic radio.It is cheap, but seems to fall short of being in excellent shape.>Now if it was an R-389 i'd be seriously tempted.I might not resist that one, or the R-725.
>>3007614Pure speculation on my part but I wonder if motor-drives were not incorporated into its design because they would emit noise?>R-725I had to look this up and i'm surprised i've never heard of it. I like to follow ASA and NSG related history stuff and I don't recall seeing this one mentioned. Interesting.
>>3007622Motor drives were already part of R-391 and R-391A, and is in any case just needed when re-tuning.
>>3005993downvote
>>3006884>>3006916and WWCR
>>3006890That's easy. The hard part is that it needs to be 1/4 wave above the ground at least at the feed point.I guess drag it into the air with a big ass drone
My TV antenna mounted on bamboo was pulling jack shit as far as FM radio stations go. So I tilted it around and I can kinda hear some stuff again. It's time for me to get my shit together though. Great SDR + terrible antenna is not the winning move.
>>3005918I have a ubiquiti J arm that needs to go up, but I read that I need to ground it?? I'm not an electrician. It's only going like 6 feet up from the side of the house for a starlink dish.
>>3007695Check your regions' electrical code. It could be for lightning reasons, and/or maybe because power is being applied to the dish.
>>3007695This is because of reasons you don't have to worry about.Basically up until like 10 years ago, anything someone was mounting to a roof connected to a coax cable going down into the house, so the metal antenna arm and antenna parts and all thst connected directly to the shield of the coax which is exposed metal om each end, and that connected to your TV or something eventually which was not grounded, so now if it gets hit by lightning it would kill your family and burn down your house or something. So grounding was required.Not a. Thing with starlink or anything ethernet/poe powered.
>>3007787The starlink documentation states that it is NEC compliant and doesn't need grounding.I don't know what a building inspector or an insurance adjuster would say though.
if i want to get into SWL for cheap, would it be better to get a standalone chinese portable radio or a USB SDR dongle? and what is the best way of getting a callsign just for listening? i've seen a few sites where they issue one for free but i'm not comfortable providing the personal information they require, so i was wondering if i should get a normal license even if i don't intend to transmit. i'm mainly interested in collecting QSL cards.
>>3007944>if i want to get into SWL for cheap, would it be better to get a standalone chinese portable radio or a USB SDR dongle?Get a RTL-SDR, it is super cheap and can also cover a far wider frequency band, can even be used for hobby radio astronomy. >and what is the best way of getting a callsign just for listening?You need no callsign or license (in all countries I am familiar with) for listening only. For transmitting you need a license.>i've seen a few sites where they issue one for free but i'm not comfortable providing the personal information they require, so i was wondering if i should get a normal license even if i don't intend to transmit. i'm mainly interested in collecting QSL cards.You can get a QSL card without a license, for receiving some of the broadcasting stations. More info on the FAQ and alsohttps://swling.com/blog/
I’ve got a TV inside a shop I work at, and the iron roof is blocking reception badly. It’s UHF 520-620MHz, would a magnetic antenna of some sort be likely to give me better reception, like a magloop in your attic? I assume a purely magnetic field receiving antenna only works like this if the wavelength is significantly greater than the size of the obstruction. Also since the electric field is horizontally polarised, the magnetic field will be vertical, which seems like it would be shielded by the iron roof even more effectively than a wavelength-matched antenna like a dipole. Would an electric field antenna work better? Can you even make an electric field antenna that has a large collecting area?
>>3007966>magloop in your attic?Simplest and cheapest solution is to draw a coax from the TV to an antenna (like a dipole) placed somewhere above the metal roof. A good antenna inside will be better than nothing but still probably bad.Metal shielding will attenuate EM waves, both electric and magnetic field, pretty strongly.
thank you, i was under the impression that i needed a callsign to receive QSL cards. are the antennas included in cheap RTL-SDR kits good enough to start? i've read mixed opinions on that
>>3008067this was meant for this>>3007946
>>3008068>are the antennas included in cheap RTL-SDR kits good enough to start?They are good enough for FM but not for SWL unless the station is close. A 10 m long wire antenna will be fine.
>>3005993you're dumb
>>3005918anyone here play around with meshtastic?im in north jersey,my id:!f68e271chit me up if your ableand does /diy/ have meshtatic threads of themselves?i enjoy not needing a "loicense for that"
>>3008197Last thread there was some discussion, it seems like Meshtastic use is dropping off in favour of Meshcore, possibly Reticulum too. You can look up online maps for these services to see how many nodes are in your area.
>>3008240Probably because you can actually hold a coherent long-distance conversation over MC unlike MT
>>3008276you have uhf, vhf and cb for that.i've used js8 on 11m it works very well.i read in previous thread that meshtastic was not scaling very well and meshcore was better.https://hackaday.com/2025/10/09/meshtastic-a-tale-of-two-cities/however. the real king is 40m nvis links.i'm sure you and a fren could try out some shit without being licensed on 40m or just below at 6980 khz or just above 7200 khz.if you are not a total faggot with spurious emissions and if you dont cause any problems, you can be unlicensed.i know guys who operate on hf here in europe and they are courteous and do not cause trouble, well they have operated for 30 years or more.
Is there a future for shortwave? I love it but it's hard not to blackpill hearing boomers talk about how much there was going on in the 50s-80s compared to now.
>>3008340use it or lose it.the hf bands are somewhat threatened by wall street jews who want to trade over it.dont let them.
>>3008340also, i'm pretty sure as the internet closes down more and more, hf will become more attractive for young people to experiment with. it is after all more than 9000 times cooler, 9000 times more autonomous and 9000 times more fun.also, since it is 9000 times slower than internet it will keep away all the hyperactive adhd retards who need instant gratification thus making it a good place for comms not polluted by crap.licensing is a good way to gatekeep but if you are careful enough, there are things you can do without a license on the same bands or outside. just dont use someone else's callsign and you should be fine.usurping someones callsign is a more serious offense than making one up yourself.in reality, a license is not a bad thing. it keeps out the most retarded guys.and those who operate without it for any length of time tend to take their own precautions and they try not to step on anyone's toes and they do it intelligently.
>>3008334>https://hackaday.com/2025/10/09/meshtastic-a-tale-of-two-cities/Some important updates:https://hackaday.com/2026/09/17/fcc-ism-rules-may-shatter-lora-mesh-communities/
>meshtastic>meshcore
>>3008604They’re saying that the minimum bandwidth is for the purpose of spreading your transmit energy out more, and so being less able to cause interference. Shouldn’t it instead be a spectral density limit? As in, a maximum amount of watts per kHz of bandwidth? A 500kHz 0dB signal is going to be much worse for interference than a 250kHz -10dB signal, in my estimation. And maybe the duration spent at that frequency matters, in a millisecond a LoRa chirp might look like a narrowband transmission, but across ten seconds it looks like a smooth spread across a wide range of frequencies. So I think the LoRa guys in the USA should rile up a bunch of the American companies that sell and use the technology to demand a clarification from the FCC.
I found this old 'Transistorized Power Supply'. Based on the address on the label, it appears to have been made by Raytheon. The unit doesn't actually say Raytheon anywhere on it. Probably from the 1960s. I have not opened it. So, CB radio PSU so you can run it off 120 volt AC power? The picture is the top of the unit and the front. It has rubber feed on both the top and bottom and it appears something is supposed to slot into it and use it as a base station. The model number appears to be 7361-5002-G1. That turns up nothing. The cord says 'Low Voltage Computer Cable'. The socket says 'Sato Parts Co. Tokyo'. Anyone know anything about this? Maybe have a catalog or service manual?
>>3009018it looks like the plug is compatible with old CB like raytheon Ray-tel TWR-1 TWR-2 :https://www.qsl.net/k5dh/raytheon/twr2.html
>>3009018>>3009022sorry forgot : maybe it doesn't deliver only 12V but also the high voltage for the lamps, so be careful.
>>3009023From that schematic it looks like the radio can take AC or DC natively, with its own transformer. If anything it would be better running off 120VAC, because that way you don't have to use the chattering electromechanical DC-to-DC converter. Maybe for some reason it also feeds DC to those filaments, instead of running them off the secondary? Doesn't make sense to me. But neither do those series filaments.
>>3009018That round 8-pin amphenol connector certainly dates it to the 1960's. That 2-prong AC plug sketches me out though. I thought this might be an external power supply for a Sideband Engineers SB-2LA rf amplifier but that unit has it's own built-in power supply so I dunno...SBE started as an amateur radio manufacturer for a few years before moving on to making quality CB radios. From 1964 on it moved its manufacturing to Japan so that could explain the "Sato Parts, Japan' socket plug. Sorry, I can't find anything on that power supply. It has a weird shape to it. And that address brought up nothing for me, not sure how you linked it to Raytheon (which btw had some controlling interest in SBE in later years if i've read correctly).
>>3009018open it up and reverse engineer its schematica solid state switcher from before the tl494 sounds real interesting
I opened the unit up and it is very clean inside. I suspect it didn't see much use. Zero manufacturer markings. It is extremely simple. A transformer, a few large capacitors, and some other bits and pieces. Basically, I just want to know what the thing is rated for. 12 volts at 5 amps? That kind of thing. Having a nice 12 volt power supply that can output a few amps, is user serviceable, and isn't made in China in good.>>3009091>That 2-prong AC plug sketches me out though.Three prong outlets were not common back in the day. They were first required by code in the USA in 1962. Note the address on the unit's dataplate lacks a zip code. They were introduced in 1963. While not everyone immediately put them on everything, they were very popular very quickly. It being missing means it is 1960s or before.See the little green wire with the paper tag on it? You can see it in the left hole on the right picture here >>3009018. It almost certainly stuck out of that hole originally. Like old power tools and stereo equipment, you were expected to provide your own ground connection. I suspect the previous owner just stuffed it in the unit and ignored it. Safety third.>not sure how you linked it to RaytheonI found it in some magazine ads and data sheets for Raytheon products listed between 1966 and 1971. I found ads for the SB-34 four band transceiver (Raytheon Company), a data sheet for a DE-723D Fathometer Depth Recorder (Raytheon Marine Products Operation), a newspaper 'advertorial' about boating in the 'The Daily Calumet' plugging the new Raycom III, and an ad for the Ray 1275 A/B radiotelephone. By 1974 it appears to have been the 'Grand Arena' roller skating rink. A staple of the area until into the 1980s.What I later found was a listing for Apelco (APplied ELectronics COmpany) of the same address in a 1962 Citizens Band Call Book. It seems Raytheon acquired them in 1958. Further research confirmed that Raytheon CBs were made for them by Apelco in that facility.
Could you put a radio transmitter and solar panels on a tiny blimp, with a microwave link to your house, and some propulsion for it to stay in the same general area? Has this ever been done before, or is this a bad idea? The reason of course being that it would provide a massive altitude.
>>3009178How would that be cheaper than just buying power from the power company? What is the return on investment on that, 75 years?
>>3009183>What is the return on investment on thatnot relying on the powergrid? priceless
>>3009183hard to get power from the grid up to the blimp mate
>>3009131Nice. I spent over 2 hours before posting that reply, looking for info and going through some back issues of CB mags without any success. It turned into a crash-course on SBE and its product history though, and I learned stuff about them that I didn't know. :^) I thought the nixie tubes in their SB-36 kinda neat.I've seen 2-prong plugs in the past on older equipment. It just alerts me to the potential of a hot chasis and to ensure all is well inside.> Having a nice 12 volt power supply that can output a few amps, is user serviceable, and isn't made in China in goodIndeed. That came from an era when bean-counters weren't interfering with engineers about the corporate bottomline. Everything in your pic looks surprisingly clean. I guess testing the capacitors and touching up any iffy solder joints would be in order. Fire it up, ideally with a variac (I keep meaning to get one) and measure the output of each pin in that circular connector. Looks like the transformer 2ndary is set for 25.2 volts which hopefully means p-p and not swinging 25 volts + and -. This is where I like oscilloscopes, you can see how clean the output is and determine where issues might be if the output isn't healthy. But at 2 amps it looks like you'll be maxing it out.
>>3009178>The reason of course being that it would provide a massive altitudeheh! You're accepting the 1/4 wave challenge on 2200M aren't you? Well, the FAA would like to have a word with you. :^)Our small radio club once sent aloft a dualband HT that has an undocumented cross-band repeat capability, on a tethered wx balloon. It was inspired by US soldiers in Vietnam who paired two PRC-77's the same way to extend the meager 5 to 7 km range on those VHF-lo radios which reportedly reached out nearly 100 km from 600 ft above local terrain.
Have any of you experienced the unsettling clarity of FreeDV? I've been parking on the calling frequencies for this mode, simply because I can't believe how amazing this shit sounds.There's not a lot of people using it yet, but I think this might be the next big thing.https://freedv.org/
>>3009356freedv is definitely ground breaking just like ft8/js8 is. it will gain tracktion with time.the good stuff gets adopted eventually
>>3009418>the good stuff gets adopted eventuallyDoes that include Reticulum on HF? Or is that a SHTF meme technology?
>>3009421if i understand the point of reticulum,it tries to bridge all tx/rx tech creating a high level network.this is an absolutely massive undertaking and requires a lot time.in theory i like it but hf is already autonomous in that you don't need an extra layer to communicate over great distances.with wifi, bluetooth, uhf, ehf, whatever, you could need it, but you might as well make a massive wifi network which already exists in many places and gear is abundant and the protocol is already built in in all devices so no need for extra layer.you could bridge wifi and hfbusing it and that may be very interesting.limiting scope makes it much more accessible and actually doable.hf is abundant enough and wifi is ubiquitus.
>>3009421and for hf, you have the old beast of ax25.its pretty much abandoned but its there, a massive update to increase the sensitivity would be in order since the tech was made back in the days when the noise floor was lower.it needs an update for sure, maybe something based on a faster type of js8 modulation to get some extra bauds in.the main thing about ax25 imo is the error correction by sending the packet multiple times until information is not corrupt anymore, so this has to happen asap.
>>3009421and ax25 is easy to link with tcp ip using plain linuxthe tech is there, the challange is the noise floor and its getting noisy these days
>>3009356that's kind of neat. listening to that grating audio could get tiresome but the potential to have your computer autorespond and give out contacts is there. no need to man your radio anymore.
>trap dipole element on fan dipole actually covers the data portion and phone portions I care about on 80m with a SWR < 2Well fuck. I wasn't certainly expecting that to happen without a lot of frustration. Now to wait until night time for signal reports.
>>3009604Some guys have all the luck. I remember helping the club construct a 40/80/160M trap dipole for FD and we (me!) must've hoisted & lowered it 15x or 20x from it's working height of 80 ft doing adjustments.
>>3007476so i put up that loop for about 90m (80m). its compacted using a vertical zig-zag like pattern (not really zig zag and quite irregular at places, the wires mostly just sags between about 40 points. its about 11 to 12m up on average.but i dont use it as is, i tried it by itself and it would not work very well on tx compared to previous setup.then i added to it fan dipole elements for specific bands, i got back some tx gain.before putting on the main feedline the loop was cut according to swr meter readings and connected with a 4m 50ohm coax.i still have to tune every element for everything above 80mseems like conditions are starting to favor 80m and down for regional contacts during the night.i tried phone and had a short chat with a station about 300km from here. he asked if i was qrp while i sent out 18w.so it sort of works on 80m now. for everything else i use fan elements and just connect everything at one point.also its hard to tell if 40m got extended as first was expected since the take off angle is theoretically lowered. since i haven't been on the radio for almost 2 weeks so I dont know how much conditions have changed in that time period. before, there was almost zero 80m activity, now i'm getting a lot more and 40m has become wider geographically, with less short-range activity in the evening with more dx.
>>3009719here is 40m overlayed. almost no local spots. only dx.
>>3009719i should clarify that there is no fan dipole element for 80m so this is the loop antenna on 80m, its the only element which can work there.its only for some specific bands above that i add fan dipole elements to increase tx gain on those bands.
>>3009604Signal reports were meh compared to standard dipole. Should have left them as separate fans. It's usable, though. I'm going to go back to separate fans. It was a nice experiment though.>>3009607I think that is all that it was: luck. Other ones I've made in the past I had to do a lot of trimming. The first time I made a 80m dipole, I had to trim that thing at least 20 times. At least I learned a lot from that first time, e.g. seeing the SWR go up as I got up the frequency goes up means I need to trim due to it being too long. Also, I learned about being able to fold it back and get the same result as trimming it. As I heard many hams say: everything affects everything when it comes to antennas.I cannot get mine up very high. It's only approximately 20ft in places and I don't feel like putting up a tower nor some type of power pole to climb. Thankfully, I just use pulleys to easily raise and lower each of the spacers I use for it up in trees.
>>3009719Thanks for reporting back. Yes I've noticed improving condx on the lower bands lately as well. Winter condx are coming back. Goodbye summer QRN.>>3009770>everything affects everything when it comes to antennas.This. That's what I experienced with that trap 40/80/160 dipole we built years ago. The antenna analyzer was giving way different readings with it on the ground vs up in the air (as would be expected). We did coarse adjustments with 2 of us, 1 on each end, trying to hold this 130 ft long antenna taut enough several feet off the ground while the older guys did the adjustments. That took several tries. Then we hoisted it up and took readings & then lowered it to fine adjust it. Multiple times. IRC we could not get all 3 bands trimmed just right so that it exhibited good SWR in the voice subbands. I think 160M was the difficult one but not so bad a manual tuner couldn't adapt it. 160M is pretty noisy here in the summer so we made the other 2 bands a priority.I just picked up a used horizontal loop antenna for 50 MHz two weeks ago and got it mounted on a tripod on my balcony. First thing I did was put my MFJ antenna analyzer on it to find it's sweet spot. It exhibits less than 2:1 SWR between 50.200 & 50.825 MHz. A slight adjustment and I got the bandwidth a bit lower as I intend to do mostly SSB around 50.125. My autotuner for 6M can't handle anything above 2:1. Hooked up the radio and wth? now i'm getting a high-SWR indicator on my radio. Analyzer back on, yep SWR is out to lunch at over 3.5. ??? Rechecked connections & tuning stub then start moving the tripod around trying to find a good spot. Move, step away, read. Multiple times. Eventually figured out that as soon as I closed the sliding door on my balcony, the metal frame interacted with it causing the SWR to shoot up.. I also found that the metal railing on my balcony is having an effect as well. I finally got a good spot. I suspect my antenna lobe is pretty funky, though.
It is difficult to triangulate and track a mobile ham radio operator?
>>3009980With three SDRs spaced out significantly, each with an accurate (GPS) time source, and the right software, it’s probably trivial. Unless the person being tracked is using a very directional antenna, such that their output is below the noise floor for at least one or two of those SDRs.If the tracker is just a single guy driving around, pointing a yagi out his window, pretty tough unless the guy being tracked is near constantly transmitting, and not moving as fast as the tracker.Are you trying to track someone? Or avoid being tracked yourself?
>>3009982>it’s probably trivial.Definitely trivial. And you can use the KiwiSDR interface for this exact task.>Unless the person being tracked is using a very directional antenna,That very rarely happens and in any case there are always unwanted sidelobes.
>>3009980if he is on the lower bands, he is most probably having nvis propagation if he has the right antenna which would make him less trackable than if he used groundwave emissions.
>>3010000With high enough frequency he could be using a parabolic dish antenna, which I bet could have less sidelobe emission than a yagi. Though at that point, the concept of being a mobile operator is called into question.>>3010025I was wondering about that. I suspect with enough SDR receivers you could probably trace it to within a few hundred km by calculating the number of reflections, but probably not more than that. With a sufficiently directional antenna and nearby obstructions (e.g. being in a valley) you could aim straight-up and get no traceable ground wave at all, I guess? Though I have yet to see a 40m yagi.I also wonder how traceable LoRa is.
>>3010048>parabolic dish antenna,Typically, the dish has to be at least 20 wavelengths across. A 2 m dish is borderline portable so wavelength has to be less than 10 cm, which is 3 GHz, which is practically line of sight in any case.
>>3010048>I also wonder how traceable LoRa is.Easy. Just remember, if you emit RF, you're trackable.>>3010050>A 2 m dish is borderline portableThat's big! I'm not sure i'd call that portable. I have a 100cm solid dish and it's heavy to set up. All the microwavers I know are using 45cm to 75cm sized dishes for 5 GHz and up.
What do I need to make my own radio
>>3010063I guess if you can tune into LoRa, you can track it, even if it’s below the noise floor for regular receivers. Though performing chirp spread spectrum on some other band, relying on security via obscurity, you might be able to stay under the radar.It would be interesting to try searching for covert chirps, I guess you feed chirps of varying df/dt values into your I/Q mixers, and average the values over multiple samples, to see if you see any spikes.>I have a 100cm solid dishWhat about an inflatable dish? Mylar on one side, regular plastic on the other side, you could make a 5m dish pretty lightweight. If you cut each side as simple circles and fuse them around the edges, I’m pretty sure the tension in the envelope would naturally form something approximating a parabola, that’s how some guys make solar reflectors.>>3010067What signals do you want to receive? Do you want to transmit too? Could be anything from a foxhole to a TruSDX.
>>3010069>What about an inflatable dish?ICould work with the lower microwave frequencies. Just have to keep the reflective surface as smooth as possible and within a certain amount of tolerance in terms of wavelength. I forgot what that is, 1/16th maybe? Otherwise phase errors creep in a all sorts of wild lobe issues.Inspired by the movie "ET The Extraterrestrial", a jr high school friend and I made a "dish" by lining the inside of an umbrella with tinfoil we stole from his mom (she raised hell) and for want of a radio transmitter we used his dad's old CB radio and a car CB antenna which we held broadside at the assumed focal point. No surprise we heard nothing. Only a few days later my electricity class teacher laughed and told us about wavelengths. A subsequent trip to the library to read up on that showed us the folly of our ways. lol We had the right idea, though. :^)>>3010067A germanium diode, wire coil, variable capacitor, and an earphone.
>>3010150>phaseI don’t see how you wouldn’t get a bunch of phase errors from a normal parabolic dish. Because the dish surface is continuous, there will be a steady continuum of phase offsets coming off the dish at different radii. A fresnel reflector could be made to avoid that, always ensuring an integer wavelength distance from the emitter to the centre of each dish reflector ring.>A germanium diodeAren’t those unobtanium these days? Nobody makes them anymore, any sticks of OEM parts seem to be snatched up by scalpers, and majority of eBay listings are fakes. The real ones were selling for $30 each last I checked.If your grandpa got away with a chunk of galena, you could surely use some sort of silicon or Schottky diode, I hear the BAT41 is pretty good.
>>3010168Oh wow.. I had no idea germanium diodes are exceptionally rare. I'll have to keep an eye out for those in the scrap bins. And I actually do own a chunk of galena, had it given to me by a guy who once worked at a now-closed silver mine.
Any VLF listeners here? SAQ Grimeton is scheduled to air on Oct 24th on 17.2 kHz.Transmission & YouTube Live stream:12:20 UTC: Live stream on YouTube begins with a technical walk-through of SAQ.12:30 UTC: Startup and tuning of the Alexanderson alternator.12:45 UTC SAQ on the air w/ "VVV VVV VVV de SAQ SAQ SAQ" (approx. time)13:00 UTC: Message transmission from SAQ.https://www.youtube.com/channel/UC-83S-l9JKD1iuhsXx3XQ3gI try every time but it's a 7,500 km shot mostly over the arctic.
>>3010195I might try to listen in, I’ve got a pretty high-Q tank circuit connected to a 2x3m loop, but I’m on the other side of the world from Europe so it’s probably not possible. Last time I was a day late, and I had to solder some extra caps to my op-amp circuit because it was picking up some broadcast radio somehow.
>>3010195Just a reminder that SAQ can be received using a notmal sound card and a SDR software package:https://dl1dbc.net/SAQ/
>>3010214That's a pretty decent sized loop. What frequency range is it optomized for?>>3010219I need to look at one of those PA0RDT miniwhips for vlf reception.
>>3010239>I need to look at one of those PA0RDT miniwhips for vlf receptionThe small reception area in those means you might struggle with weak signals. Big single-turn loops coupled into a transformer core seem better for VLF.Also a built one of those mini whips and I must have fucked up somehow, it doesn’t work for shit. Gotta troubleshoot that I guess. Maybe a USB isolator on the SDR will help.
>>3010242The serious guys seem to use custom loops. I wonder if adding a long whip, or long wire, to the mini-whip unit would be beneficial?On a side note, last night I was listening around VLF and hearing nothing interesting I went up into the AM broadcast band and it was wall-to-wall signals, many with overlapping stations. About an hour in i'm experiencing a lot of co-channel interference and mixing issues. I heard numerous stations not on the usual N American 10 kHz spacing. I was picking up reasonably good signals coming from Japan and S Korea! Spent 3 hours logging them before I forced myself into bed at 4am. Ran some distance checks, the S Korea one on 972 kHz was the farthest at ~7,200 km. Surprisingly, nothing heard from the russian far east.
>>3010267The mini whip is designed as an unbalanced electric field antenna, it isn't obvious to me how you'd add a loop to it.Just making it longer should help, though I wonder if using a thin length of wire would be significantly different to using a wider conductor with the same length could be better. I know collecting area is important for magnetic field antennas like loops, but I suspect it also matters for electric field antennas too.Electronics Unmessed on YouTube has some pretty good videos on the topic of ELF loops.
>>3009982>>3010000>>3010025I just thought it would be funny to troll sad ham boomers from my car while driving. No continues transmissions just short snippy burts while mobile
>>3010286Sure. Sure.
>>3010286>I thought it would be funnyYou have some growing up to do.
>>3007687does it have a preamp? they usually have band cut filters for anything that isnt tv stuff
>be me>just got generals license>really excited to just listen to 20m since it's so active in my area and mayhaps say hello>start buying gear>suddenly antennas>don't know which to buy>buy the DXEngineering Nomad telescoping mast alongside with the EFHW Feather 60ft antenna so I don't have to tune my antenna>gear comes in, finally set up in my backyard>antenna is long as hell, made do with the space I had>SWR was off the charts kek because my antenna was touching the ground and forgot that the ground absorbs rf>set up again the next day, untangling my antenna by hand and undoing any kinks I made the first set up, this time setting up the antenna dangling across a garden trellis >finally, SWR is at 1:5:1 >having fun listening to all kinds of random conversations>decide that the set up is too jank, since the telescope mast is just weighted in a backpack and is not practical for SOTA or POTA which was something I anticipated doing also>buys the HF 010 from Radioddity>comes in the mail, set up time>one of the extension rods has a messed up thread, I was super gentle with trying to screw it on too>give up temporarily on HF because money contraintsmfw antennas are the biggest hurdle for me
>>3010286Touch grass?>>3010332Often the VHF preamp includes the 100MHz broadcast FM radio band. If it's a UHF-only antenna though yes you'd be right.>>3010333Gotta make your own. Join the wizards.
>>3010333What >>3010334 said. It's cheaper, you learn more, and many times, the results can be interesting and sometimes surprising.
>>3010333its funny there are really two kinds of people, people who get license and then start to figure things out and those who figure things out, throw together antennas, put them down, make mistakes, even start transmitting before the license and then one day, they finally get licensed.
I bought a pack of 'feng mini 5s (seemingly a new revision of the uv-5r mini) and I'm pretty impressedspurious emissions are well within legal limits, and it doesn't seem like it gets overloaded nearly as bad as my previous baofeng (purchased in 2018)perhaps I just got a lucky batch
>>3010268Thanks for that link, he has some interesting stuff on there and a couple of unknowns he's captured in the VLF band which have piqued my interest. I just had one tonight on 35 kHz very briefly. Will be watching for this one.I went on the AM broadcast band right after I posted that message (No.3010267) last night. Again, LOTS of asian stations but this time they seemed to be clustered above 1000 kHz. I heard 31 stations, several loud and clear but many just 1 or 2 kHz from a NA station so it was challenging to pick pick them out. I think this is when a loop would come in handy to null out the locals. A total of 48 stations in a 48 hr period. Tonight I only heard a few very weak carriers of 3 stations.Anyone know where beacon "SGX" on 346 kHz is located? I find no listing for it.
>>3010371sgx sounds like singapore but i don't know
>>3010371>Anyone know where beacon "SGX" on 346 kHz is located? I find no listing for it.Sure that was not YXL in Sioux Lookout, Ontario, Canada? That matches the frequency.
>>3010408Yes i'm pretty sure. I've got a recoding of it, I had it on a narrow filter and then switched to a wider 500 Hz one at the 17s mark:https://litter.catbox.moe/y2sgsj.wav>Oct 4-2026 07.38Z 346 kHz CWN + CWW
Ok maybe my mini-whip wasn't showing any difference with/without power because I was testing it on 100MHz FM, and the thing supposedly has a bandwidth of 30MHz. An SDR that only goes down to 25MHz isn't very useful for HF, I should get me a dongle with an upconverter. Also the MKT film caps are apparently bad for these frequencies, not sure if they're worse than Y5U or X5R ceramics (nonlinearity could create harmonics), but I'll see if I can track some NP0s. No clue why it uses 100nF caps when even 10nF would work fine to receive 520kHz broadcast AM. People actually make NP0 10nF MLCCs, which is nice.
Huh. I wonder what's on 8101 khz?
>>3010794If the signal is at 8101 KHz, why did you end the diagram at 8050 KHz?
ya know those ufl to sma 'splitters' for use with dual antennas->1 receiver? Can I just make my own by just soldering 2 sma cables together and running it into a ufl ,mmcx, or other connector?
>>3010797Aww.. dammit. I meant 8010 khz.>>3010800You could, but I think that changes the nominal impedance the radio "sees". Also technically it's a splitter so you're cutting the recv'd signal in half. I'm looking into an active combiner myself so I can share a single antenna with some receivers.
>>3010800Are they antennas of different frequencies? If so, I’d want to make a diplexer. The ones that use tuned lengths of coax are simple looking, though I think they’re intrinsically resonant so they’re narrowband compared to LC diplexers.
I’m looking to get a somewhat cheap RX-only SDR to upgrade my TV dongle, in order to listen to signals below 25MHz. I’m looking at either an RTL-SDR Blog V4L, or maybe an RX-888, but I’m open to other options. The 16 bit reception of the 888 looks nice, and it still goes up to 1.7GHz with the 74CBT3253 acting as a quadrature mixer. Though having just an HF-only direct sampling SDR with a 30-64MHz bandwidth and no mixer seems like it should be cheaper, if anyone sells such a thing. Though I’d still probably want something to upgrade my TV dongle above 25MHz eventually.A bit of a browse suggests the Chinese clones aren’t worth chancing, they often use fake chips and have worse manufacturing tolerances, but if there any reputable off-brands I’m keeping an open mind.
>>3010854Take the RSP1B pill
>>3010854>or maybe an RX-888, but I’m open to other optionsThere is also the Web-888.
Let it be known that I have had a very enjoyable first summer of HF with an indoor 20m EFHW antenna strung around my tiny Manhattan apartmentIt is possible
>>3010881Maybe? Compared to the 888, it’s only 10MHz bandwidth, and only 14-bit. The switchable filters look nice, but manually making and swapping filters would be a lot cheaper. It goes down to 1kHz instead of 10kHz, doesn’t seem too useful.Will that extra 2 bits of resolution on the 888 be useful?Either are still kinda expensive, does nobody make a single ADC channel direct-sampling-only SDR for HF?>>3010900The Web-888 is like 3 times the price, I’m not exactly looking for a web SDR.
>net control, this is j1zz, the hurricane has made landfall here. We're seeing maj->CQ POTA CQ POTA
i live in a dense city, all buildings around me are at least 3 stories high.has anyone used drones to put up horizontal antennas over rooftops?
Can someone help me make a radio with just a wooden board, resistors and a couple of usb cables? I don't have a spool of copper wire.
>>3011042Wires sitting on top of rooftops don’t make good antennas. They need to be at least a decent fraction of a wavelength off anything that isn’t a good insulator.Set up a magnetic loop antenna of some sort.>>3011043What are you trying to pick up? If you want to make a crude AM radio, the easiest types are simple diode detector types. But they all require quite a few turns of fine (magnet) wire, and some sort of diode detector. Maybe you’ve got a dodgy speaker or pair of headphones to disassemble, but you’re not going to pull it off without being able to wind an inductor or two. You can also make a dodgy diode from a rusty razor blade, like the POW camp foxhole radio.
>>3011046well, i figured using two chimneys as supports for a guide lines, the actual antenna wire would not be directly on the roof, there'd be like a meter between the roof and the antenna elements.i'm more thinking about the weight, would a drone handle pulling a heavy speaker wire?
>>3011042No, because drones are impractical to use. Don't overthink it. If you managed to get a drone strong enough to lift a wire up, or a leader string, how do you plan on fastening the antenna to the chimneys?1 metre above the roofline is not ideal, as >>3011046 says, especially if you are thinking of transmitting. If for recv only and it's the best you can do then go fo for it, it's certainly better than nothing, right?
>>3011046I have 1N4004 diodes laying around
>>3011056it would just go around the chimney and come back with the guide wire. the antenna wire would be fastened to the guide wire and would stop before reaching the chimney,the drone would go around it and bring back guide wire.one leg of a dipole could go to one chimney and the other leg to another chimney, i have a bunch of chimneys, the houses are 100+ years old made of bricks., anyways, i dont have money for a drone that strong anyway. thats the main problem really.for now, my attic is fine, i'm doing qsos with a 40m around my country (about 500-700 km radius.) mostly via nvis propagation.
>>3011042please see >>3010901I literally am in the worst possible situation and can make it work with an indoor EFHW
>>3011089good for you.i already have antennas in the attic at a height of about 11 to 12 metres. a linear loaded 80m (linear loaded L-shaped horizontal) and a 40m (L-shaped horizontalbut i love radio so much that i'm ready to try some crazy shit.i also tried loops 1x wavelength on 80m and ran it on a bunch of bands with the g90 but keep coming back to dipole variations.if everyone was happy and settled for what was possible, we wouldn't be trying the impossible shit. yeah sounds cliche but its true.
>>3010816>you're cutting the recv'd signal in halfI figured as much, but it's more about redundancy so 'some' signal is better than no signal considering I can mitigate the loss with higher gain antennas no?>>3010819no they are the same freq but I found an ebay seller who makes nice mmcx to dual sma connectors anyway.
>>3011098if i'm not mistaken the noise is also cut in half, you're basically getting the same signal to noise ratio as before but everything is just weaker (including the noise) so you'd have to use a pre-amp on each receiver to amplify the signals again. or you could put a pre amp before the splitter, so as to amplify the signal before it gets cut in half.
>>3011059Reverse recovery time of 1.5us, 20pF junction capacitance, they're too slow for any radio use I say.
>just got yet another piece of junk mail from ARRL>still asking "pls join us again, we need monies to pay us to do nothing">after being an operator for 7 yearsFFS, get the damn hint. I do not want to join.
Man, turns out RF capacitor selection is a real pain. X7R ceramics are fine for bypass capacitors, but for filters it seems like a requirement to use C0G ceramics, or silver-mica capacitors. And these C0Gs still have self resonance, 100nF caps seem to be normally down below 10MHz, for HF use you may well have to stack a bunch in parallel. Higher capacitances make for lower self resonance frequencies, and so do larger packages, but I don’t want to try manhattan soldering 0402s. Multi-layer is apparently better than single-layer, but THT options above 100pF are slim pickings. Silver-mica caps are just expensive.So I think I’m going to do an LCSC order of a few different sizes of 0805 C0G caps, 100pF to 100nF. Nice Murata ones. Any other ideas for RF caps? Any magnetic cores I should be buying too?
>>3011375oh cool, lcsc is stocking a bunch of fair-rite cores soon
Has anyone ever blown finals in a VHF/UHF radio before and determined what the cause of it was?
man, you can buy rf bjts rated to like 60ghz for less than a dollarany reason not to use these in my vhf and hf receiving circuits?
>>3007476>Now if it was an R-389 i'd be seriously tempted.There is one on eBay just now, a bit expensive so lots of people are just watching.
>>3011769>$2,500Yowch! That's ~double what I thought they went for. But then it is greed-Bay and radios are usually over priced. Imagine the shipping cost on that. There's a local here who has one of these, it works but doesn't look as pretty. as the one listed. I got a shack tour and I didn't realize how rare these are until I went home and looked them up.
i think i've reached attic potential.this the current fan dipole configuration:85m (+30m harmonic, 10.2 mhz)45m (+15m harmonic, sort of, more like 16m)20m (+ unused harmonic)11m (+ unused harmonic)so it covers 85m, 45m, 30m, 20m, 15m, 11m+10m.using the built in tuner but it would mostly work without it except for 10m band and some other lesser used ones.a bit worried it might not be as efficient as stand alone antennas but it seems to work for now. using 20w ssb phone up to about 600km on 45m and up to about 300km on 85mi'm ready for the global internet shutdown.
>>3011876What’s your roof made from, is it conductive?
>>3011882i doubt it since its old ceramic shingles with some bituminous tarp under them i think.its a really old building.but i'm not convinced yet that a fan dipole is as efficient for a given band as a single band antenna is.its hard to judge since propagation is fluctuating so much all the time but i seem to have gotten a worse phone report when it usually works alright, its a guy maybe 150km from here.ft8 reports have been less dense as well but its hard to tell.any opinions on fan dipoles?
>>3011900No clue about fan dipoles myself, I was just wondering about putting antennas inside my house, but it's got a corrugated iron roof so probably not. Even loop antennas might struggle, I'm not sure how a 3-30MHz magnetic field reacts to sheet iron.
>>3011882btw, 45m is bent slightly and 85m is severely bent almost in the middle of each leg, 45 degrees.overall, receive is quite bad, lots of noise, hard to hear people, they seem to hear me better than i hear them. the noise is really awful sometimes, everyday, pretty much S5 in noise.
>>3011903whats the height of your attic?
>>3011906Maybe 1.5m at the peak. It's also just a space of beams and insulation batts, not a proper space to store things or whatever. I was thinking more for getting reception with a big loop around a full face of a room instead of inside the ceiling itself, I'm not yet wanting to drill holes to the ceiling. Though the access hatch is in a hot water cupboard from which I could definitely run a hole down under the house. I already have coax going down there.
>>3008350>HF will become more attractive for young people to experiment with.So the thing with no retard proof guides, that requires lots of space and monetary investment is going to all of a sudden be popular with young people?And doesn’t the FCC just send you a strongly worded letter if you end up broadcasting w/o a license?
>>3011876what frequencies is 85 and 45 m? I've never heard them being called that.
>>3011922>monetary investmentThis would big the biggest filter for young people.
>>3011947>>3011922a txeiver is like 300 to 600 usd, an antenna can be as cheap as 0 in many cases, not everyone buys ready made antennas. feedlines etc over the period of experimentation could cost 50 to 100 usd, add to that another 100 and i'd say for around 800 usd you can get everything up.once its set up, assuming you're happy with results the cost is limited to the power consumption which is a small fraction of a gaming pc when averaged out.
>>3011791The R-390 and R-390A are more reasonably priced, so the seller probably realised these are rare.If you know someone who has got one, you might ask to listen in when SAQ fires up in a few days.
>>3011935you can lead a horse to water, but you can't make it drink.
>>3011375> Any other ideas for RF caps?Back in the day, we’d make our own.In some cases, out of literal tinfoil and polyethylene sheet. Especially for “high voltage” RF.We test and adjust them with a known good value, putting them into a wien bridge oscillator and a frequency divider so we could hear it. Inevitably, you eventually build some kind of frequency counter though.I guess you have dedicated capacitor testers now eh? I had never really heard or used the term “esr” for the first 40 years or so, but now everyone is all abuzz with esr this, esr that, and my esr is better than your esr, and showing up to swap meets with your dedicated digital esr meters clipped on your belts.
>>3012013For big HV caps yeah I’d definitely look into making my own, but at the moment I’ve got a little mini-whip RX-only antenna where I’ve used off the shelf 5mm pitch THT MKT film caps. They have a self resonant frequency in the low MHz range (here it’s ESL thats the real kicker) so they’re unsuitable for HF use. I’m not sure what makes a silver-mica cap suitable for RF use, while a polymer film is not suitable, I assume it’s the geometry, but AFAIK film caps are made as a jelly-roll with schoopage on either end, that shouldn’t introduce any significant ESL. Maybe I just need smaller packages? Maybe someone makes RF polymer film capacitors, I’ll look into that.Also buying some high frequency analog switches to make quadrature mixers seems like a good idea. Like for sound-card SDR use.
>>3011983>If you know someone who has got one, you might ask to listen in when SAQ fires up in a few days.And that is today: https://www.youtube.com/watch?v=qcw60OCIosUhttps://alexander.n.se/en/saq-grimeton-scheduled-to-air-on-un-day-oct-24th-2026/
i like how you get "coverage belts" around QTH when using the same antenna system on multiple frequencies. note how they line up.i suppose its what happens when working multiple bands with the same antenna assuming there is one element or they are on the same height from ground.the belts in europe from inner to outer: 40m, 20m, 15m and 10msame thing happens at night but shifted down one or two bands
>>3006797What’s the best/easiest way to make an overkill antenna for one of these? I have a big penthouse balcony and want to rig it with coop antennas listen to Russian talk radio and other weird shit.
>>3012790>I have a big penthouse balconyIt better be big.
>>3012416Once again, no reception of SAQ in the NE Pacific region but an attempt was made. Had access to a RF quiet location w/ a 500 metre Beaverage antenna pointing towards Australia (120 degrees off of Sweden). Low Kp index.I read that the signal was barely heard on the USA east coast but generally heard across Europe. I'm curious to know how much power they were running. I suspect it was not at its maximum output.Great video, btw. It never ceases to impress me watching them fire that up.
>>3012809I wish I could a copy of that final .KMZ file here:https://googleearthcommunity.proboards.com/thread/246/soviet-krug-cdaasInteresting that almost all of the USA ones have been demolished while other nations have been expanding theirs (CDAA's). Another big one being constructed as we speak in Kalinningrad:https://en.defence-ua.com/news/russia_constructing_huge_antenna_25_km_from_poland_to_spy_on_nato-15569.html
So I have been sniffing around different ways of communication and alternative networks, but still something that is automated. Ie not making a radio phone call, but something that could potentially get around ISP or ur traditional provider.So there seems to plenty of ways to communicate, but a true alternative (large) network never seemed to have taken off. Is there any reason for this? It seems like, technically, if there was enough will you could have an alternative snailmail type of internet. Radio frequencies are regulated ok, but light gets you 20 km. The "wifi can" movement had DYI'ers at least a km. I'm legally radios could get you quite far as well? Put this on cars and golden.
>>3012846Reticulum in principle is a robust decentralised networking protocol that can be used across any medium, and has been to varying degrees. For low-power semi-local use it's been sucessfully implemented over LoRa, while there's a project to allow it to talk over HF too.
>>3012845> Given its long detection range, it is not clear why it was placed so close to the border. With a range of 25 km, ordinary artillery could easily neutralize it in the event of hostilities in the region.> Nevertheless, this new antenna poses a serious threat to NATO and increases tensions throughout Europe, with no current means of neutralizing it.I got an idea, hey zel, here’s a couple mil and 4 stormshadows with the coords burned into them already. Do whatever you want?!?!
>be me, russian in russia>buy baofeng and long antenna for shits and giggles>listen to fire dept comms, mobile AA technical shouting obscenities during drone raids, construction crane operator, bouncers in local club etc>recently start hearing weird comms with coded phrases like "mama is ready to dump on sector 45d" and so on>young male with the voice of dagestani wrestler btw with specific accent, shit is hilarious>thought it was some retards joking around>speak random phrases in similar style into that frequency>it goes silent immediately, so I forgot about it>days later see a giant hexacopter hovering above my street, roskomnadzor car with a bunch of antennas on top making circles, glowie looking uncles with huge backpacks nearbywhat was it i have no idea
>>3012865In 2026, do actual security and military organisations actually use unencrypted analog voice radio comms? The hardware would be more expensive, but you'd probably be able to manage longer ranges or less bandwidth with a digital voice encoding scheme. Not sure how you stop stolen radios being a problem on the front line, password unlock? Maybe you do everything with codewords so encryption wouldn't matter?
>>3012869yeah, I wonder as well. Digital encrypted devices are expensive because of demand on the frontlines, local PMCs tasked with AA duty deep inside Russia mostly use cheap baofengs for quick coordination. I asked around and it turns out there's a big pimple from kremlin visiting soon, so I guess it was some security stuff checking roofs and shit for sleeping drones
>>3012859>Given its long detection range, it is not clear why it was placed so close to the border.It was probably placed there because it's located on military land that butts up against the airbase at Chernyakhovsk, 5 km to the north. And about 15 km southwest of this new site is a rather large brand spanking new Kontaynor OTH radar site which should be up and running soon. Definitely a strategic asset.Looking at the CDAA's placement, being the most western one Russia has it will provide more accurate fixes. But holy cow is it huge. I think there have only been 2 or 3 that big. I wonder who will be operating it? GRU or FSB. There is only one other CDAA in operation in Kaliningrad located near Lesnoe and I think that one is run by the GRU.Co-ords for the new site if anyone is interested: 54.56360868119663, 21.827365416184804
>>3012845Just a receiver? I wonder if having three or four of those spaced around the Ukraine frontline could help them locate specific signals very quickly? But then what kind of signals would they be looking for? Remotely operated UAVs or radar guided weapons? Radar ground stations? Radio comms? My impression was that a lot of those things would be VHF or UHF, while a quick search suggests those arrays are HF.>>3012865>>3012874Do you think they triangulated your rough transmitting position? Or were they looking all the way around in the vicinity of where your transmission was received?Also hope you're following proper opsec, glowies and gommies browse this place.
>>3012790EIther: >>3012809or Skyloopor >>3006890On the last one, make sure you centerfeed it for best results.
>>3012845One UFO weblogger mentioned that one of the US elephant cages has been brought up to speed again and more cars were parked around the area. Also in the news, US Morse code operators are once again being trained. Seems someone discovered Morse was back in fashion ands had problems skimming it.There was a rumour of a Russian elephant cage 1 km across but I never saw it. If this is 1600 m across it will probably be the largest, even larger than the German Kastanette.
>>3012884>Just a receiver?They are mostly used for fast and accurate direction finding, using R-390A receivers connected via a goniometer. Less common, these can also transmit directively in narrow beams.Western Wullenwebers operate in the HF band but Soviet Krug could cover some VHF, not sure how they did that, especially as these usually have just a single ring. There used to be one Krug near Odessa.
>>3005918Just gettin into radio comms and what I’m seeing so far is basically>boomers that like the sound of their own voice, think the world is still 1969 >schizo preppertypes that “don’t trust the internet” without eleborating>soiface lookalikes that are there purely for some kind of childlike fun>ghostnet minuteman larpers running cibil war fatasies in their head 24/7I do find the DIY nature of this topic interesting and it seems to deselect the consumerist archetypes that totally consumes most other topics peripherally related to preparedness. Any oldfags know, do these various groups get along or nah?
>>3013031The larpers and preppers tend to piss off the boomers and soifaces due to their general disdain and/or disregard for the rulesThough there's places where it all overlaps and people mostly get along like with unlicensed stuff (i.e. lora meshes)
>>3012951>that one of the US elephant cages has been brought up to speed againThat would be Elmendorf, the rest have been dismantled. Interesting if true.>There was a rumour of a Russian elephant cage 1 km acrossI've heard this too but have never found any evidence for it so far. And the original German one was said to be as large yet documents and testimonies found show they were only about 200 M in diameter. So I am not sure where the "1 km" figure originated. This new one is a monster. Imagine the ground system for it.>but Soviet Krug could cover some VHFThis piques my curiosity, do you have a source for this? I've heard the same claim elsewhere. It really doesn't make sense to me unless they specially modified some of their THICK8's to pick up the low power portable VHF-Lo band comms that NATO units used during the cold war. But even then I think hauling some portable DF system up into the hills near the borders would be more effective. Some of the old ASA units used to do that to peer into Czechoslovakia from mountains in West Germany.
>>3013159>ElmendorfYes, I think that one matches. Most FLR-9 and FRD-10 are gone but there are smaller ones across the world, plus the Kastagnette in Germany that I think is one of a kind.> And the original German one was said to be as large yet documents and testimonies found show they were only about 200 M in diameter. At the time it must have qualified as enormous.>VHF-Lo band commsI never saw evidence or even an explanation. Then again I never saw any explanation for the baroque details of pic. related. VHF low bands can at times have propagation well beyond line of sight and might have some utility, otherwise I must agree that smaller and portable sets are more plausible and useful.Do you have a closeup of the various Soviet krug systems?
