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FAQ: ftp://50.31.112.231/pub/radio_FAQ_Preview8.htm
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Recently passed my intermediate licence. Got my callsign last week, although I haven't used it yet, which means I can now use up to 50w. If I didn't have to open the windows to run my coax through I'd have probably made a few contacts by now.

I've got an FT450D on my desk here which I've made contacts on using my foundation licence running the maximum of 10w.

I was also playing with Fldigi the other day, I was feeding it audio from a WebSDR (http://hackgreensdr.org:8901/). At first decoding some morse and then last weekend some PSK. Really makes me want to get an audio interface, though it would probably be cheaper to build one.
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>>1573816

Air Force RF Transmission guy here, I used to work right next to the FLR-9 in Misawa. Unfortunately, they started tearing it down in 2014.
>>
>>1573816
Always admired elephant cages. Tho those are for DFing. Here is one of the sites I worked at.

35°48'29.6"N 139°28'21.2"E
35.808218, 139.472542

10KW HF Rockwell Collins HF-80.
>>
>>1573852
Bummer. I was out there doing GWIP (Global weather improvement program) boondoggle.
Those are impressive up close.
>>1573977
is at Tokorazawa Japan, the Smoke Signal III site. Now HF Global.
>>
I bought a yaesu ft227 memorizer, Anyone know how I program my glorious single channel memory?
>>
Are there any interesting ham devices that can run off PoE? I've been meaning to get my licence, but I'm so busy with other things that it'll probably be another year or two before I do. However, I am planning on running some cables across my property to connect up security cameras so I can stalk thieving junkies. Just wondering if I should stick in some extra cable for future interesting uses or not...
>>
>>1574092
Funny you should mention that since I just picked up a few Linksys routers to start a mesh network. If you look up “hamnet” on YouTube you can find a ton of info but basically you will need a router, antenna, and PoE adapter (and associated cables) to get started. They cheap route (which is what I did) is to buy a certain kind of router that has a specific amount of RAM and onboard memory plus a programming language in Linux. Then you need and antenna, and while the stock antenna works for very short distances you’ll need a directional one to join a mesh. Put the router in a waterproof enclosure close to the antenna to minimize loss and run a LAN cable to your computer with the PoE adapter hooked in somewhere in between. Another option is to buy an Ubiquity device which is already waterproofed and do the same procedure after getting it close to your antenna. I’m not sure how useful this setup will be without the custom firmware from hamnet but the good news is you won’t need a license at the stock frequency (though I don’t know if that applies to Ubiquity)
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>>1574126
I'm guessing they use openwrt with some sort of ham radio module they've developed? That could be an option, I should probably ask the local radio club if there is anything like a meshnet set up here.

Often we don't have these nice things in Australia except for Sydney and Melbourne, because of our cities' low population density (even lower than America). So anything that relies on high density to be practical (good Internet speeds, public transportation, mesh networks, etc.) either isn't very good or is very expensive.
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>>1573816
>>1573852
Why disable a HFDF system? that seems extremely valuable to me.
Is there something better to replace it with?
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>>1574092
cant you just run real electrical wire along with the ethernet cable?
>>
>>1574260
I could, and I probably will for some sensor lights, but I'm not sure how that would help with what I was asking...
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>>1574272
Now you're not limited to interesting ham devices that can run off PoE, you may also include interesting ham devices that can run off AC.
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>>1573816
I don't like what they've done with stone henge desu.
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>>1574336
Well, the reason why I was thinking of PoE is so I can easily control it from my house.
>>
>>1574260
>>1574272
You guys know PoE stands for power over Ethernet right? As in you only need one (Ethernet) wire to your router instead of two.
>>1574143
There’s no “module” it’s just modified firmware that makes the router operate on a slightly highe freuency that’s password protected.
>>
>>1574678
>You guys know PoE stands for power over Ethernet right? As in you only need one (Ethernet) wire to your router instead of two.
Yes, of course I know that...

>There’s no “module” it’s just modified firmware that makes the router operate on a slightly highe freuency that’s password protected.
Well I'd just use openwrt then, if that's all this hamnet firmware does.
>>
>>1573816
How representative of the technician tests are those I find online?

They all come from the same pool, but is it random or more of a wink wink?
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>>1574936
You can literally download the whole question pool from the fcc newfriend
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>>1574936
Tech is a seriously easy cakewalk. Rote memorization will allow you to pass. However, if you actually want to enjoy the bands, also study for General. If you pass Tech, you can take General for free that day and get 1500 watts and privileges on all the bands.
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>>1574936
>>1575231
>http://www.arrl.org/tech-question-pool
>>
Hey people, I have recently developed and interest in radio as an alternative to satellite communication in a potential SHTF situation and while many of the books I find are informative they also deal mostly with the theoretical aspects of it, are there any books or manuals that treat radio manufacturing and repair in more practical DIY kind of way?
>>
>>1575908
Basic electronics repair will get you there; circuitry is circuitry. You may want to find some books on audio electronics repair.

You may want to get:
Energy Choices for the Radio Amateur
ARRL Handbook (2019)
Power Supplies Explained
Portable Operating for Amateur Radio
and
The Radio Amateur's Workshop
from the ARRL store: http://www.arrl.org

Also, snoop about QRZ.com Lots of SHTF people post in their forums.
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typical ham
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>>1575231
Correct, but that's 400+ questions.
Online pulls from those, but in a disporportionate ratio - ie I see the same questions time and time again.
I'm guessing the FCC has picked a core group of questions which these quizs iterate through, then throw in a few random questions so there are alternating versions.
Any ballpark as to what % I should be hitting to be confident I'll pass the actual test? I'm in the 80%s and have a month to go. Maybe I should just switch gears and study the General exam.
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>>1575940
>I'm angry
>I'm so dense, I can't get my ticket
>I'll try to persuade others it's stupid, too
>stupidHAM.jpg
>I showed 'em good!
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>>1574071
engage the 'M' latching switch
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>>1576407
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>>1574146
The idea was that the bad guys just want to leave HF since HF takes more effort. That was a mistake. According to a UFO guy who believe these are UFO technologies, he noticed more cars in the parking lots around these sites than before and concluded mothballing has been reversed.

And once again we see how much leaks thanks to pieces of openly available information.
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Hi guys, I'm still in the planning stages of a solo transatlantic trip next year, I know most bluewater cruisers use VHF for local comms, what would be some good budget equipment for both VHF communications, and separately, OTOH comms? Taking that further, I see a bunch of radar systems with a max range of 48nm. Are there any affordable OTOH radar systems out there?
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I'm interested in using wifi hardware in amateur radio in the UK. I'm aware of HamWAN in the US and was wondering what parts of US band plan it uses.
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>>1578133
Look for the 13cm and the 6cm bands and compare to common WiFi frequencies.
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>>1574126

The only ubiquiti radios that need licenses are the 3Ghz and 11Ghz radios

The performance with a DD-WRT router is garbage, I've run the setup myself and the ubiquiti hardware will give you solid performance.

I had an 5Ghz AP serving a client over a mile away and the radio had an uptime of over a year. Look for used hardware.
>>
>Guard freq. is CB for pilots
>https://www.youtube.com/watch?v=DYCcaIelB_U
>https://www.youtube.com/watch?v=hS8kPPK_rYY
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Is there any point to doing this if you dont want to hear boomers all day?
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>>1578504
what fucking frequency is that?
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>>1578815
121.500MHz
https://en.wikipedia.org/wiki/Aircraft_emergency_frequency
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What are kind of HF antenna are these?

This photo was taken in London.
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>>1579429
Was that an embassy or the British Foreign office? These usually have a lot of long distance HF capabilities.
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>>1575940
This is not inaccurate, but not a bad thing either unless you're a neat freak. it's not like he's surrounded by garbage and piss bottles.
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Hey lads,

I have my technician, going for general in a month. Bought a house recently and there is a ton of RFI that I haven't been able to identify from all the samples out there, wondering if I could post a few samples here to get some opinions on the sources.
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>>1580823
Turn of your breakers one at a time until the noise stops. If it doesn't stop, the problem is outside the house.
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>>1580824
Yeah, that's my plan for tomorrow. This board moves pretty slow though. Just wanted to make sure I wouldn't be a cunt if I posted some .wavs in a few days.
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>>1580830
Sure thing. What you can do when your comment doesn't merit a bump of the thread is to put the word "sage" in the field Options.
For example, I put it in the options field when I posted this because it doesn't really forward the discussion on topic.

Your .wavs are on topic. Should be fairly safe. Polite sage if the .wavs are posted in individual posts instead of all once.

Have a nice day. :)
>>
If anyone of you is a Chink engineer working at Baofeng Pofung, please create some UV6R sporting:

- digital modes
- APRS, SSTV, morse, etc
- QRP
- Arduino-compatible board inside (let's say an Espressif also doing GPS and Wifi), able to read/write data (serial), morse (digital pin), signals/mic/speaker (analog pins) and status (e.g.: "this digital pin is high if carrier is detected")
- on board keys and graphic display shall be available to the user programs as well
- no need for voice modes because everyone already has a flock of gadgets (including UV5R) to transmit his fuckin voice over fuckin radio
- battery shall be charged at 5V because we're fuckin' sick to use a fuckin' new adapter for every gadget we buy
- battery shall be usable as a power-bank because fuckin' ham radio enthusiasts on the field literally need their fuckin cellphone more than their fuckin radios

It doesn't matter the power. Having 4 watts output and a shitty antenna is useless (UV5R anyone?). Let's have a 1 watt (or 0.5 watts) output and a decent antenna.

Please, Baofung!!
No other radio manufacturer would sell such a thing.
Why the fuck noone of them ever had the "Arduino radio" idea till now?
>>
>>1580830
get some type of battery so you can power it while turning all the power on/off
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>>1581037
There was a discussion on a future K4 on the Elecraft mailing list along similar lines but that was shot down. I guess they have little choice really, many of the components are reaching end of life, through mounted components are disappearing giving way to surface mounted and much smaller devices. Their DSP lines have ended in the past. And I hope Elecraft is brewing a nice K4 soon. Hopefully with a better DSP choice than in the past. A multi core DSP for baseband, IF and audio/data would be close to what is done in mobile phones the last 10 years. That way the panadapter could be a standard part and fed from the DSP.
>>
Seen a better shack than this?
http://www.n1ul.com/n1ul_nj.htm
>>
Any good ham related 1.st April jokes this year?
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>>1585577
I've seen two good ones:

1.The FCC announced this morning that is brining back the coding requirements for all hams even those currently licensed. Technicians and Generals will need to pass a 13 wpm test and Extras a 25 wpm test.

2.The FCC has announced changes to testing procedures for the amateur radio service. All hams will be required to show competency in digital modes and computer technology by building a computer, installing FT8 , and perform 10 QSO's with their radio.

The amount ass devastated radio autists in the comments section on fagbook was sight to behold
>>
>>1576279
I'm finding the same thing as this fella.

Basically every technician test I take online or on the app I downloaded I see the same questions again and again and again, almost every test I see the one where component 6 in figure 2 is a capacitor, knife-edge diffraction lets you connect around an obstacle, coaxial cables fail from moisture intrusion, and tower grounding is controlled by local electric codes.

Maybe I'm just bad at assessing randomness?
>>
Anyone have an opinion on the cheap Chinesium mobiles? The TYTs and whatnot with 25 watt output. I'm just wanting to get a cheapo to use as a base for the local repeaters since I mostly work HF on my TS-590SG but figure I should have some 440/144 ability beyond my handhelds for the sake of emergencies.
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>>1576279
VE here (one of the guys who give the exams)

Dirty little secret: Each ARRL license level has 5 test books, meaning you will get Tech-2018-1 through Tech-2018-5. Only a maximum of 175 questions in the pool are used for tech and general (and in reality, tech and general test books 1-5 reuse 20-25% of the questions in each one where the correct answer is moved around).

The tech pool is easy enough to memorize as it's very basic stuff. General actually has about 10% of the same questions as tech, just reworded slightly.

Extra and its 750 question pool/50 answers was the only difficult one for me. It took me two times to pass.
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time to start studying for General
and figgerin' out a radio to buy
any recommendations for a cheap mobile radio to stick in my truck appreciated
also looking for an antenna that's not a million miles tall so I don't smack it into the top of my garage.
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>>1587755
Grats on your ticket. For a mobile, are you just looking to work the local repeaters on 2 meters/440?
>>
>tfw the Elephant cage is no more
That thing was big, as a kid I always wondered what it was.
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>>1587208
yeah im working on studying for my general. i mainly have trouble with the math questions, because im awful at math.
>>1587755
great job getting your ticket!
how much are you looking to spend? 2m/440?
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>>1587760
>>1588611
Yep the 2 meter/440 repeater scene. At this point I'm hoping to find a basic radio without tons of frills just to use to get comfortable with ham etiquette and practice. Once I get to general/extra and have expanded frequencies and power to work with I'll revisit and buy something more advanced. Right now I've got my TYT UV8000e handheld and a mag-mount but no whip to use with the mag-mount. I drive a big SUV that barely fits into my garage (door release cord drags across my roof rack) so I don't want to run a big whip on top. I'm not sure if mounting a larger whip down by the side mirrors is the way to go, or something more compact in the center of the roof for the best ground plane.
>>
Is there any good way to make use of repeaters when on a road trip without owning a modern rig with a GPS receiver that picks what repeaters to scan by comparing your current coordinates to a database of all the repeaters in the country, or maintaining a large book of repeaters and trying to add/delete them from your radio based on which ones you may be able to hit at the time? Are there any other ways to solve the problems of:
>there being too damn many repeaters in the country, to the point where memory could actually be an issue on a longer trip if you don't have a higher end rig
>the low number of those repeaters that are actually active, and you will have no way of knowing which ones in advance
>low scan speeds that makes simply entering all repeater outputs a non option
>there being no standard for how repeater tones are chosen so that even if you did enter all repeater outputs and didn't miss what little activity you may hear due to low scan speed, you can't easily access a repeater without kerchunking it with every tone until it works
>>
>>1588671
well....your price bracket would help. many such options
as for antennas, you could run one through your am/fm antenna spot. personally ive been partial to diamond antennas, only because ive never had a problem with one.
>and a mag-mount but no whip to use with the mag-mount.
can you post a picture?
>>1589202
not really. unfortunately nothing seems that coordinated
>>
Help me out with my back up power supply math, guys: If I use a fully charged 12 volt rated for 20Ah and my radio draws 0.5 amps on RX, I'll get roughly 40 hours of RX, correct?

And if I draw 8 amps on TX, that would account for 2.5 total hours of TX time in total (assuming I turn it on and somehow make a 2.5 hour transmission), yes?

Final dumb question: If I want to connect two 20 Ah batteries for a total 40 Ah, is that series or parallel?
>>
>>1589768
>Final dumb question: If I want to connect two 20 Ah batteries for a total 40 Ah, is that series or parallel?
Connect in parallel. If you do it in series the voltage increases probably beyond what the equipment can handle
>>
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Stupid question but would these worwork for HAM stuff? I have such a boner for military radio handsets and it'd be kind of fun to use for stupid reasons.
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>>1590572
probably, could make a nice little go kit out of one, you just need to find the right connectors.
>>
Idk if this is the right thread but the prev owners of tge house Im at left an old dtv dish behind. Anything fun or cool i can do with it or is it mostly junk?
>>
>>1573816
Passed my Tech yesterday with 31/35. Missed General by one. ONE!
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>>1590711
Radio telescope.
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had to laugh as yesterday at the stop light some faggot pulled up in a ford ranger and it had 15 antenna all over it from front to rear I never seen anything as fucking stupid in my life
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>>1592021
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>>1592021
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>>1592141
Jesus, and I feel cringy have a Diamond dual bander on my 2017 Focus.
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>>1592140
>office chair in the van
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>>1590711
You can make your own weather radar.

>>1592013
Also this. The rtl-sdr is used for this, cheap and cheerful.
>>
>>1592141
Fuck, if you had a porsche, would you dare risk parking it anywhere near a car like that?
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>>1592140
KB9EVB expired 79 days ago. He must have Silent Keyed.
>>
>>1592327

It looks like an impound lot more than anything.
>>
>>1592538
Nope, that's an electronics swap meet in MO. Tom Vogel was eccentric and the red porcupine was some sort of 'statement' in his mind. You should have seen it just before he passed, it had even MORE antennas.
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>>1593359
>some sort of 'statement' in his mind
Pic unrelated to the late Mr. Vogel
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>>1593398
and here i am, wondering if my diamond SRH77CA is a bit too long to be walking around with
>>
>>1593398
Oh, sweet mother of god. And I was worried about putting an open J-pole on my house...

>>1593402
Kind of regretting tossing my rubber duck for a 771 now.
>>
>>1593405
>And I was worried about putting an open J-pole on my house.
oh, my house is a different story. i think i have 7 or 8 antennas up outside
>>1593405
i do wish the rubber ducks were a bit better. they just dont do enough for me where i am.
i bought a fake 771, it sucks so bad, i really need to get a real one.
perfect size
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>>1593407
>Be me
>More of an HF guy, like to DX
>2/440 Baofeng for repeaters
>Get annoyed I can't get into ONE repeater with ARPS traffic
>Build J-pole
>Get a Yaesu Mobile to use as a base
>Can finally get into APRS Traffic Net
>Never check in

In the years since I did all that, all I have done on 2/440 is check into a single Skywarn Net when we were Green.
>>
>>1593414
that sucks... ive made a bunch of good friends from my local club and other repeaters.
we are also starting a "antenna erection" team to help people put up their antennas
its nice to find a group of people who arent retarded and get shit done
>>
>>1593418
It's like the same 7 guys on every repeater in my area. One guy who is always on is what I call "The most boring ham in the world" who can turn a tidbit about a sandwich he once had into an hour long story and there's a real nasally guy who turns everything into obnoxious sexual innuendos.

And then there's a guy who whispers into his mic so close it over attenuates.

I like most of the guys and gals at my club, but because I'm fairly young, I'm constantly asked to do repairs/ladder climbs, et al for the Elmers and it gets annoying.
>>
>>1593421
maybe i just got lucky. there are a few that are pretty awful, but most are cool and helpful. im the youngest as well, and have had to be up on smaller towers, but we have people in the club that like doing that.
>>
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>>1593359
>and the red porcupine
100% original idea pls do not steal
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>>1586130
http://www.hamradiolicenseexam.com/index.html

This site (not free) will teach you the material, or just make you brute-force memorize every question with practice exams. (Study Mode or Test Mode). I passed Tech and General the same day 3 yrs ago using this site, and my Extra last week the same way. In either case I had about 2 weeks of study an hour or so each day.
>>
>>1593534
You can also just rote memorize the question pools for free on: http://aa9pw.com/amateur-radio-exam-practice/
>>
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>>1592304
>>1590711
You can also use the SDR + Dish to download satellite images of the weather pretty easy.
https://www.youtube.com/watch?v=yLp3My8jUvo

Until SDR, you needed a $10,000 machine to do this. Pretty good resource if you bug-out/off grid yourself.

>>1591837
Grats on your ticket. You have a radio yet?

Also, you'll get your General next time, but DO get it. The band privileges are significantly better. If you need to save up for an HF rig, you can use RemoteHams.com to play around once you have your General.
>>
>>1573816
where can I find a decent handheld CB radio?
Me and a few people are going on a road trip and I want to stay connected to them. The area we are going through has shit cell service and if something happens or we need to talk I want them to be able to hear me.

I'm not sure where to start. I don't want it to be expensive since it won't be used that often but I also want one that works
>>
>>1594392
Go to Dicks or Cabela's and get some FRS radios. 2 pack is like $20.
>>
are FRS better?
I already have a car CB radio and from what I've heard CB can reach further. We might get separated at a turnoff and with FRS i'd never be able to contact them
>>
I want to upgrade the antenna on my UV-5RTP

What antenna should I get? Size doesn't matter
>>
>>1594402
>size doesn't matter
I mean I'm ok with getting a 20+ incher as long as it's not longer than me
>>
>>1594399
FRS are good for car to car. CBs don't work well from inside a car on an HT. Cheaper if you're rarely going to use them for car trips like that.

>>1594402
I have the Nagoya 771 for my 8 U5-RV V2+ radios. They work really well. I can tag most repeaters in my area from my basement with those that I can tag from my base station and Open J-Pole.

Mostly just use those radios for public events and SAR and never had issues.
>>
>>1594412
>FRS are good for car to car. CBs don't work well from inside a car on an HT. Cheaper if you're rarely going to use them for car trips like that.
alright I'll look into FRS
thanks!
>>
>>1594412
>Nagoya 771
Perfect
I go on a lot of hikes and It's nice to have a basically a free satellite phone with me. If you need help all you have to do is ping the nearest repeater, no need for an expensive satellite phone plan
>>
>>1594423
I've experimented with hooking two UV-9R 10 watt radios together to make my own repeater, placing them high up near base camp/rally point and programming all the UV-5Rs to use my homebrew repeater.

Really good for teams in valleys and what not. I'm going to make a solar/LiPo battery pack for the UV-9 setup because the experiment drained their packs pretty fast.
>>
>>1594423
If a man is dying in the middle of the woods and no one is monitoring local repeaters at the time, does he make a sound?
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>>1594426
There's always someone listening. I'm always scanning all of mine but rarely answer a CQ unless it's an actual emergency (twice).

Hell, I accidentally connected with a repeater in Pori, Finland at 0400 hours their time on Echolink and 5 Finns with terrible English hailed me.
>>
>>1593841
>Until SDR, you needed a $10,000 machine to do this.
Did that in the 1980s with a TRS80 Color Computer and a cheap shortwave radio. Nowhere near $10k of equipment.
>>
How is this shitty hobby even /diy/ related anymore? Today it's mostly just full of buyfags and wackers who actively try to discourage anyone who's interested in doing any tinkering and insist that one needs to start with dropping a ton of money on a full power HF radio at home before one gets into any /diy/ aspects more complicated than making your own antenna. Most amateur radio enthusiasts seem completely clueless about their gear as well, leading to ridiculous claims being common such as you being better off using a full power HF rig hooked up to a memenetic loop antenna indoors when you live in an apartment than you would be with anything lower power designed to be portable and hooked up to a dipole at a better location like a park because retards just think about how many watts the radio is putting out and don't consider anything else.
>>
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>>1595630
But then anon... Watt is true power?
>>
>>1594445
Ha, oddly enough I'm working on a packet radio client for the TRS-80 Model 100 at the moment.
>>
How do you push really high currents through antennas to achieve high power outputs? Isn't an antenna just an open circuit to the air? How would I push 100A into an open circuit if I wanted to? Surely I can't impedance match it, the impedance is too high and is impossible to calculate accurately and will also vary with air pressure and humidity and that sort of stuff.
>>
>>1595644
The simple explanation is that an antenna can have an impedance of about 50 to 100 Ω, with most being designed to be 50 Ω.
Thus, you can (roughly) calculate the current as I=V/50.

The more in-depth answer involves dealing with free-space permittivity and working with complex numbers in the frequency domain. At radio frequencies, you can't think of the antenna as just an open wire, because the antenna has inductance and capacitance. As frequencies increase, the capacitive elements start to become electrical shorts and the inductive elements begin to look like open circuits.
I wish I could give a more detailed explanation, but I don't really have enough background to completely understand antenna black magic myself.
>>
Newhamfag here.
I want to do the fox hunts
From your guys experience are all the clubs filled with boomers or do they have a good number of 20-30 year Olds?
>>
>>1595784
it really depends. just go to a few of them, if you can to check them out. my club is pretty active, and most of them are very helpful.
pretty easy to build a radio direction finding antenna. pvc, an old tape measure, and a short length of coax with whatever you want to terminate it with.
>>1595630
yeah, the only thing ive really been making is antennas.
i dont know how i would build anything close to the ic7300 or something like that.
>>
>>1595642
fucking carlos...
>>
>>1595789
I built a directional antenna and fox hunted with wifi Hotspot before but as you'd imagine wifi isn't very long distance and not hard to track down
>>
>>1593841
>You have a radio yet?
Just a Baufung. I'm looking around for something else, but I'm not sure where in the house it'd go and I'm cheap.

I do want my general - went by grandpa's yesterday (rip) and saw his 80 meter Hallicrafters which he'd listen to Germany at night, halfway across the world.
>>
>>1594392
Be a man - get your ham!
>>
>>1596324
I'm studying for the ham license
But if the people in the other car don't have a license and have no interest then how do we communicate?
>>
>>1595809
nice. i went to look for my antennas but cant find them....hopefully they are in the clubs locker

project for today is to make a quick 20m dipole, hopefully ill be able to use 6m as well.
band was pretty open this morning.
>>
>>1596426
just buy 3 baofengs and use them. just keep it on the frs channels
its also illegal
>>
>>1596457
Is there a way to make the radio low power so it's legal on frs? Or is it illigal no matter what to use baofeng on frs
>>
>>1596462
Illegal no matter what, since Baofengs are not FRS certified.
But if you turn the power down it should be indistinguishable.
>>
>>1596462
itll always be illegal. but gotta be safe!
just use low power and dont be a cunt.
if you stop at a few rest stops, some drive thrus use frequencies around there, dont quite remember what ones.
>>
>>1594397
>>1594399
>>1594412
>>1594415
>>1596457
You guys do know that using any radio with the antenna inside your car is going to greatly limit how far you'll actually be able to communicate, right? A CB radio with a magnet mount antenna would be the propper solution here. Illegally using Baofengs hooked up to magnet mount antennas may run into problems depending on where you're driving, due to the front end overload issues that Baofengs can have when hooked up to better antennas.
>>
>trying to fix VCR but fail
>notice colorbust crystal
>devide to try to build a simple transciever and try messing around on HF
>listen around 3.579 MHz at various times throughout the day on various web based SDRs across multiple states over a period of about a week
>only CW traffic I hear near that frequency is from W1AW
Fuck everything.
>>
>>1596557
holy fuck reddit go back, the memefengs with work fine with ducks and driving
>hurrrrrrrrrrrrrrrrrrrrr get a 10' cb whip guise and attach it to a cigar box with wires to shove around in the car
>>
>>1596662
>the memefengs with work fine with ducks and driving
Only because you've never used anything better. Hopefully that anon and his friends don't end up with a few miles between them.

>>hurrrrrrrrrrrrrrrrrrrrr get a 10' cb whip guise
Do you not know what a magnet mount is?
>>
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>>1596687
>Only because you've never used anything better
jesus. why do you sound like this
fuck off with your faggy cb bullshit
>>
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>>1596586
I built this. works.
>>
>>1597190
nice
>>
>>1597190
Interesting. What frequency and how much emitted power?

Also, how about harmonics? I don't see a pi filter here.
>>
I just got a baofeng and noticed it can revive FM radio.
Is it possible to transmit on lets say 99.9 mhz on ultra low power?
>>
>>1599128
no
>>
>>1599128
No, the UV-5XXXXXX radios were designed to receive FM Broadcast so you can listen to emergency broadcasts or entertainment but the chipset can't be altered to transmit below 120 MHz .
>>
>>1580483
Makes sense. An embassy is the perfect use-case for an HF transmitter. A lot of opportunity for atmospheric skip and EME propagation. Diplomatic immunity spares you the hassles of license and crypto restrictions.
>>
>>1593534
>>1593813
http://hamstudy.org is free and helps you find/sign up for an exam with a VEC in your area.

The flashcard study mode is very nice. I qualified for all three licenses using that exclusively.

With an account it remembers your progress and syncs across devices. You can buy their offline android app for 4 bucks, but you don't need it.
>>
>>1599199
C looks good.
Why is it that so many techies do not renew their license?
>>
>>1599207
10 years is a long time
>>
>>1599207
>>1599239
You have a two-year grace period to renew, too. The license isn't valid during that time, but you don't have to re-test and your callsign won't drop.

The ARRL automatically renews for members, but it takes more effort and attention to periodically renew ARRL membership than to renew with the FCC. If you want the luxury of forgetting about it ARRL lifetime is $1220. Pretty steep and you can buy some nice kit for that.

My advice is to set your preferences to "paper" in the FCC license manager. Every new license you get they'll send you a printed copy of the long-form license and a card. You can also get PDF on demand, of course. Laminate the card and carry it in your wallet. You'll likely hang on to the shit in your wallet for ten years.
If you don't have an account with the FCC sign up for an FRN here: https://apps.fcc.gov/coresWeb/publicHome.do
>>
>>1599364
Tnx fer info. Is it still so that your license is only valid in the state you did your exam and your call sign also changes when you move elsewhere?
>>
>>1599207
>C looks good.
Yes. Conventionally R is +X and L is +Y. 2π is about 6, 18 is about 20, and 120*3.5 is about 400. Since MHz and µH cancel, Pont 3 should be right.
>>
>>1599454
No. It's never been like that to my knowledge.

Your U.S. license is good in

>all 50 states
>U.S. territories and territorial waters
>foreign nations with bilateral operating agreements

For this last see: http://www.arrl.org/bilateral-reciprocal-agreements
>>
>>1599454
>>1599670
I should add that the FCC will -suspend- your license if they send you mail and it's returned to sender because you no longer live there. You're required to keep your address current with them even if you move down the street.
>>
I just sat on my baofeng call button and it transmitted a tone for like 2 seconds

Am I gonna get foxed?
>>
>>1599723
run
>>
>>1599723
No, but it's good etiquette to rekey, say, "This is (callsign), sorry about that last transmission, it was an accident."
>>
>>1599723
Was it a repeater?
If so tell someone next time you're on. Word will get around.

Everyone does it once.

If not, you're good on simplex freqs. Most people will attribute it to 12y/o's.

If your were listening to public safety or government and accidentally transmitted...

All I can say is prepare your anus for bubba.
>>
>>1599768
It was just some random amateur radio frequency that I was scanning through.
446.something mhz
440-450 have been quiet all day for me so I doubt it interfered with anyone. I don't know the exact frequency it was but if I hear someone bring it up I'll be sure to notify them that it was me
>>
>>1599723
>>1599782
lol no one gives a shit whether they heard or not. you have to be really making a nuisance of yourself over a period of days or weeks before anyone cares enough to fox you.

Most people can get away with using simplex freqs unlicensed all day erryday. Your 4W handheld only has a range of like 400 yards. If someone with big ears hears you and doesn't like it the first thing they usually do is TX on that freq and ask you to stop.

Anyway repeaters use CTCS for this very reason.

I just got the ARRL's 2019 repeater directory. Fucking useless no one buy it. Doesn't tell you what the CTCS freqs are if a repeater is using different tones for input & output.

It's funny, when I google "ARRL faggots" for an appropriate reaction image the second hit is this thread.
>>
>>1598876

~5mW,
It uses the "color burst" crystal (very popular). The crystal can be found in VCRs and TV's.
https://en.wikipedia.org/wiki/Colorburst
The frequency was bit lower than 3.57954MHz
This circuit will work with crystals of other frequencies as well.
It could be heard up to 10KM away.
Long wire antenna run up to a tree.
A pi filter would certainly help clean up the signal and is a good idea.
It was a bit "chirpy" as it was keyed on and off.
Source is sparkbangbuzz dawt com

One benefit of not having the filter is that you can test receivers at harmonics. Up to VHF!
>>
Received NOAA18 and 15 today, haven't gotten the recording setup right and haven't made a good antenna for it but now at least I know it passes over in 'hearing' distance. Any pointers for a specialised antenna for it? Read that a QFH is supposed to be good for it but if anyone has a better idea, do tell
>>
>>1600738
Can't say I've had better success than with my 3/8" copper tubing QRF antenna. A Yagi is going to require you to chase the signal manually (PITA) but a Helix's design pulls the signal well while being stationary since it picks up the changes in signal axis as the sat passes by.
>>
>>1600536
>Source is sparkbangbuzz dawt com
Thanks.

Seems a lot of transmitters are lacking proper filtering. Also the Pixie leaves a lot to be desired. I was thinking of making a PCB with inductor traces to overcome this problem.
>>
>>1601078
they sell filters for goes
https://www.nooelec.com/store/sawbird-plus-goes.html
>>
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>>1600738
135 - 152 MHz
higher gain at lower elevation
>>
>>1601558
Yes, SAW filters for GHz band. I was more thinking of the HF band.
>>
>>1601859
i need to be building more ham stuff. i opened up a balun box from DX engineering and they dont seem like much. seen a bunch of homebrew hf filters on field and they looked pretty easy to construct as well.
>>
>>1601078
How important is it to avoid coupling between the inductors in a filter?
>>
>>1604073
Especially in inductively coupled filters.
>>
Anybody going to dayton (xenia)?
>>
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>>1573816
Mobile question - I want to swap out the OEM AM/FM antenna(bottom) with a 2m antenna (top).

I've located the antenna cable inside the cab. Would all I need is to find the threads and get a male-to-male conversion bolt? Is it possible or a good idea? I don't use the radio and would prefer a stealthier look.
>>
>>1605411
Looks like it'd be best to replace the whole antenna gear with an L shaped NMO bracket. Now to find out if they exist.
>>
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Sorry for my ignorance about this subject. Alas, I was the kind of crummy teenager that might have enjoyed "trolling" or "griefing" ham boomers, if I had had access to someone's radio. Who would have stopped such a youthful rapscallion, assuming that his usage pattern was irregular enough to frustrate triangulation? (See also: >>1606160) Does the FCC roam the country in party vans scanning for rogue operators? Or would the local boomers have gathered for a witchhunt at the VFW hall with their torches, hunting rifles, tallboys, and Harbor Freight gas generators to power a mobile minutemen triangulation squad? Is ham trolling a problem, or is it limited by the relative rarity of radios, compared to the ubiquity and "bang for the buck" of Internet trolling?

Legal notice: This extremely valuable meme image was adapted from the following original photograph under the Creative Commons Attribution-Share Alike License. Note that the adaptation for memetical purposes did not include the caption, "Breaker Breaker 1-Niner, Describe Bobs and Vageen", which would have been quite tasteless.

https://commons.wikimedia.org/wiki/File:VU3LWD.jpg
>>
>>1606721
Every club in my area has at least one psuedo-Doppler radio triangulation unit. The second you start QRM/illegal broadcasting on a repeater, they will call the guy with the PDTU and in as much time as it takes for him to turn it on, they will have your location in 5 to 20 feet.

Since the clubs do this for the local police when they get QRMers, the cops are happy to knock on the door of a QRMer on amateur bands in return for the favor.

Had two Arabs singing the Prayer Before Battle to each other on a local repeater one night, our PDTU located them, we forwarded the info to the local cops and FBI office and never heard them again.
>>
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>>1606733
Thanks for answering. Interesting; did not know that such units existed to make triagulation so quick & accurate. Also, for those who (like me) did not know, "QRM" is apparently jargon for "human-caused interference", according to Internets. (And presumably in the cited case, their use of the repeater was actually illegal, and they were not reported for simply speaking "foreign" in a town without a falafel joint.) So is the dude with the "PDTU" like the Chad of the ham club?
>>
>>1606733
That's really interesting, is there any further reading you can recommend on this pseudo Doppler triangulation with regard to the hardware or software involved?
>>
>>1606753
>>1606733
Bump for interest
>>
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http://byonics.com/tdoa/
I built one of these. However, I used a 555 timer instead of the PIC.
It let's you direction find to within a few degrees. If you had two rotating in different parts of a city, you could biangulate a signal easily.

Perhaps track signal strength/ audio strength/ rotation angle with your favorite flavor of electronics.
>>
>>1606920

Thank goodness for the waybackmachine!

https://web.archive.org/web/20180212065727/theleggios.net/wb2hol/projects/rdf/tdoa2.htm

This is what I built and it works well for manually tracking down frequent sources of interference (cheaply).
>>
>>1606922
My club has one of these, but never looked into how it worked, cool stuff! Explains why I need to find the null tone
>>
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https://www.he360.com/
Is this the end? This company is putting up a constellation of SIGINT satellites equipped with SDRs capable of receiving on frequencies from somewhere in the VHF range or possibly lower (receiving CB activity is mentioned in a couple articles) all the way up to the Ku band and locating transmitters within 1 km or better, and they are going to sell those capabilities to any company that wants them. The idea that you aren't safe from companies tracking you even if you're out in the middle of nowhere using frequencies that won't normally go over the horizon is ridiculous. How low of an ERP would be necessary to avoid stuff like this, assuming you aren't taking advantage of others using the same frequency at higher transmit power levels nearby or other methods of masking your signal? I know that amateur satellites such as SO-50 get by using 250 mW into a 1/4 wave antenna on the 70 cm band, so I figure these SIGINT satellites could detect you if you were transmitting at a similar power into a similar antenna.
>>
>>1595630
>How is this hobby diy anymore. Some people gave advice I don't agree with.
>>
>>1607264
The US has done this for years; it is mentioned in the FAQ. HF is safer, less leaks out past the ionosphere.
>>
>>1606922
Works best under carefully staged conditions, unusable in a multipath environment like a city.
>>
>>1607264
>any company that wants them
All four major cellphone companies have just been hit with a class-action lawsuit over allegations that they sold their customers’ private location data.
>>
>>1607336
>The US has done this for years
Do you not understand the difference between the US government having a capability and every company willing to pay having that capability? The average person is significantly more likely to have various companies spy on them and actually use data collected on them than they are the US government.

>HF is safer, less leaks out past the ionosphere.
Sure. You just need to make sure to go really low for best results considering current solar conditions.

>>1607384
...and? It's been known about for years that cell service providers will sell your location data. This company's satellites massively expand that capability to usage of other frequencies that don't have infrastructure for devices operating on those frequencies everywhere.

Also, those cell service providers are just being sued because they got too specific with the data they were selling by not poorly "anonymizing" it and requiring the company on the other end to due the work to deanonymize it. Only reason they're being sued is because they got greedy and tried to get away with selling the capability to directly look up someone's location by their name.
>>
>>1607264
I love tkmiz.
>>
>>1607264
How will they find out that you are you in the middle of nowhere, can they remote-scan your DNA like the TSA does to spot the hybrids?
>>
>>1607599
Cross refrencing with other data, the same way companies manage to attribute all of the other data they collect that didn't come with personal information attached to specific people. Data points can also be correlated to each other because people tend to have routines that they follow.
>>
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Can anyone advice on the purpose of this antenna?

Sorry for terrible quality, my phone has dust in the lens
>>
>>1607264
>capable of receiving on frequencies from somewhere in the VHF range or possibly lower (receiving CB activity is mentioned in a couple articles) all the way up to the Ku band
On some further research, the coverage is supposedly from 100 MHz to 15 GHz. The satellites use 3 AD9361 transceivers that are capable of tuning from 70 MHz (which makes me wonder if the minimum frequency may be lower) to 6 GHz and can each tune to a separate 56 MHz chunk, combined with a series of antennas with downconverters that each transceiver can switch between. I suppose everything under 100 MHz is safe for now, although Europeans could need to worry about being monitored on the 4 meter band if the coverage does end up actually extending down to 70 MHz. I guess at least I don't have to worry for the time being and have time to prepare for the inevitable upgrades these satellites will receive further down the line. Time to start messing with FM satellites so I can possibly get a better idea of how much power you'd need to be running to be detected by these SIGINT satellites.

A rather detailed article I found on it:
https://directory.eoportal.org/web/eoportal/satellite-missions/h/hawkeye

Here's a presentation that goes over some of the capabilities as well. The second link is the slides.
https://www.youtube.com/watch?v=WlXi2UyOLLE
https://www.gnuradio.org/grcon/grcon18/presentations/gnu_radio_and_rfnoc_in_space_how_hawkeye_360_uses_gnu_radio_on_small-satellites/11-EJ-GNURadio_in_Space.pdf
>>
>>1607643
That's a dish and either a HF verticle/whip or j-antenna.
>>
>>1592141
Codename Porcupine.
>>1592207
I've got a 20 meter whip and I take it off when I park so fewer people break into my car, and to not look too duschy
>>
>>1606733
HT can get away with a lot more, right?
>>
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>Good morning Mr. Phelps
>Lately the ham radio technology has become stagnant. Very little has happened on the analogue front end beyond what we knew with R-390A/URR. At the same time DSP technology is a mainstay of mobile telephone technology. Short of some modest developments on digital modes, very little DSP innovations can be seen in radios. The Secretary has decided this cannot continue.
>Your mission, should you choose to accept it, is to construct the R-400/ORQ.
>As always, should you or any of your IM Force be caught or killed, the Secretary will disavow any knowledge of your actions. This ka-baomfeng will self-destruct in ten seconds.

OK, what do?
>>
>>1609151
stop green babble
>>
>>1609160
>I am uncultured.
Please. And do you have any contributions? There was a discussion about K4 on the Elecraft mailing list and it was a major exercise in vagueness.
>>
>>1609151
get an Airspy HF+ and fully embrace the SDR gods
>>
>>1609565
Does it have good filters on the input? not entirely clear from the descriptions.
>>
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>>1609776
If not good enough, add a preselector.
https://www.rtl-sdr.com/tag/airspy-hf/
>>
>>1610033
Details are a bit sparse but this is more disturbing:
https://www.rtl-sdr.com/our-review-of-the-airspy-hf-compared-against-colibrinano-airspy-mini-rsp2-rtl-sdr/
Seems the design is not as good as it appears. The importance of the analogues front end should never be underestimated.
>>
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>>1607264
>>1608345
http://www.satmagazine.com/story.php?number=2060893990
>HawkEye 360’s station-keeping requirements throughout the planned, three-year smallsat design lifespan
>three-year smallsat design lifespan
>these satellites are going to get upgraded every 3 years
RIP. With the clock already ticking down for the first upgrades, simply using a frequency lower than what the SDR on these can receive is only guaranteed as a very short term solution. It's really time to mess around with amateur satellites to see how low of power is necessary if one doesn't want to resort to radios on the 80 meter band or lower in order to not be tracked by these satellites.

Does anyone know how much lower than the threshold for understandable speech one can go signal strength wise and still be DFable via TDOA or FDOA?
>>
>>1610424
No one will pay to find out what you do with your Feng.
>>
>>1609565
>This kills the curmudgeons who think their 1980s boat anchors are still an (((investment)))
>>
I'm ignorant about ham stuff
what is OP's pic?
>>
>>1610488
I never heard Boatanchors described as investments. They are now for fun. The analogue RF front end tends to be good.

>>1610501
No ham would ever afford such an antenna. It is the legendary Wullenweber, and the 300 meter diameter earned it the nickname "Elephant cage".
>>
>>1610488
Do you plan on transmitting with that? Boat anchor Tx for the win.
>>
Why it is so important to protect your antenna: https://youtu.be/cZkAP-CQlhA
>>
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>>1611024
Mysterious periodic DGPS range loss.
>>
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>>1608543
You were definitely right with the HF verticle, found out the other day he has his general license. Thanks for the info!
>>
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http://www.m0nka.co.uk/?page_id=740
what's the difficulty level on this kit, it looks fairly hard, and my skills are scrub level, I want to buy the version with the smd components already on, still has anyone done it?
>>
>>1612015
>difficulty level
It is worth pointing out that the kit requires some advanced soldering skills and knowledge in electronics as mods might be required. Also extensive tuning and calibration might be needed, or sometimes debugging of problems. It is not recommended as first kit or if you expect to be on the air after few M3 bolts tightening.
http://www.m0nka.co.uk/?page_id=2
>>
>>1609160
K4 is now officially announced after the leak.
>>
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>>1612089
*yawn*, fanboys..
"expect first deliveries to begin in November"
called k4 because you have to deposit 4k
>>
>>1594445
True, but I think we can all agree it's never been more accessable.
>>
>>1612032
>>1612015
I am looking for commentary from someone who has built it,
>>
>>1609565

I ordered an R2 mini today for a project I'm working on.
>>
>>1610424
Well, I was able to get some brief quieting when trying to pick up SO-50 using a Baofeng with a 2 3/4" long rubber duck antenna off an old FRS radio. I also tried calculating the path loss (142.6 dB assuming 40 degree elevation and 600 km altitude) and subtracting it from the noise floor figures that AO-91 and AO-92 report in their telemetry (ranges between -120dBm and -130dBm) and realized that those SIGINT satellites will be able to detect some really weak signals, as in 18.2 mW to 182 mW EIRP around the 70cm band. I guess the next question is how much coverage one can even get on land while using low enough power to maintain less than x% chance of being DFed by those satellites, considering even FRS radios would likely put off too strong of a signal.
>>
>>1612015
A group is making an open source version of this, how far have they gotten?
>>
>>1612372
Maybe you should stick to carrier pigeon.
>>
>>1612814
Short range carrier pigeons? Smoke signals or a wistle might be better for shorter ranges.

In all seriousness 70cm or higher at very low powers is still usable for some purposes, but performance seems to drop off for lower frequencies that will still make it past the ionosphere with how much you need to reduce the power to deal with the lower path loss. On the 70 cm band, 10 mW (what LPD433 radios in the EU will do) is safe for everything except > 70 degree elevation passes with a -130 dBm noise floor so long as you aren't using a 1/2 wave dipole, and 100 mW (like what some 70cm HTs can be turned down to) into a rubber duck will be the same down to a -125 dBm noise floor. I wish I could get some more detailed information about the noise floor in space that wasn't from a satellite that only monitors the frequency that people are trying to transmit to the satellite on.
>>
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>>1612814
tried and trusted
>>
>>1612552
>A group is making an open source version of this
Can you post a link to them, i'm interested.
>>
>>1612930
>I wish I could get some more detailed information about the noise floor in space that wasn't from a satellite that only monitors the frequency that people are trying to transmit to the satellite on.
Well, I just found a paper on the data I was looking for and apparently the noise floor in space is really fucking low, to the point where the capabilities of the receiver setup that the satellite is using seem to be the real limit in many cases. I guess I can't really go much further with this without knowing about the specifications of the recievers and LNAs they're using on those satellites, as they could perform better than the satellites I was looking at the telemetry data on the noise floor from.

>but performance seems to drop off for lower frequencies that will still make it past the ionosphere
On reading more and running the numbers, this is the opposite if the satellites can actually reach down to the noise floor, and lower frequencies will work better for getting good coverage while not being above the noise floor by the time they get to the satellite. Otherwise it just depends on the receiver capabilities on the satellite.
>>
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>>1573816
Serious question.

Why the fuck is anyone interested in this?
This was a cool thing in the 80's. It's current year.
You can pull out your cell phone and call people.
You can talk to people on social media.
You can talk to people on 4chan.
You can talk to people on Discord.
You can talk to people on forums.
You can talk to people on IRC.
You have so many fucking options I can't list them all?

What is the fascination with HAM radio?
>>
>>1613632
>What is the fascination with HAM radio?
The groups of people getting into it today mostly fall into one of these groups:
>people who just enjoy messing with technology that people like you take for granted because of how much they use it
>people who enjoy being able to do even a small portion of any of that stuff that you listed without being dependent on billions to trillions of dollars worth of infrastructure that's beyond their control
>people who are interested for practical reasons, such as communicating in areas where there is no cell phone coverage or need a party line push to talk system (such as storm chasers)
>wackers
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>>1613647
Are preppers group 2 or 4
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>>1613677
I think most preppers land more in group 3 or maybe 4 depending on their attitude, since they're really just into it for the sake of using the gear. Group 1 and 2 are people who are actually interested in the hobby beyond just using the gear and sit on a sliding scale of how practically minded people are, ie people who don't like FT8 and other digimodes that serve no practical purpose beyond contesting would lean toward group 2.
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>>1613632
some people REALLY like listening to old people bitch that young people aren't interested in their hobby.
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>>1613632
> It's current year
And it's still a cool thing. Being able to communicate with no infrastructure necessary has always fascinated me.
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>>1613647
I want to be able to control a fleet of drones over a very long distance
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>>1613632
Just because it's fucking cool you can hear or be heard around the world with 100W of power or less. Receiving satellite images is amazing. Being able get communicate easily when you're driving in a caravan
or out in the middle of the woods with no cell reception. Tracking airplanes. Getting a signal to bounce of the moon and back to earth. Tracking an animal that has a low power transmitter. All those things you list need existing infrastructure. I can climb a tree, hang a wire for antenna, hook my transceiver to the solar panel trailer I built and communicate when SHTF. HAM radio is a big community of people doing research (in some form or another) to keep people connected, even when disaster happens and everyone is panicking that they can't get on the internet. It's a hobby like any other. Can ask the same thing about people's fascination watching sports (that have mostly been the same for ages) if you can play them yourselves.
>>1613647
I fall pretty much under each group.



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