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1500 questions
4
votes
2 answers

What is "Meter" referencing in "60-Meter Band"?

I know that there are various bands referenced in meters (or cm). My question refers to what exactly the word "meter" is referring to when identifying the 5MHz band? I know that the 60-meter band is 5MHz, and considering that communications on that…
4
votes
3 answers

Recommended 9:1 unun core type(s)

I would like to construct a 9:1 unun that connects my QRP transceiver to a random-wire antenna. The transceiver's antenna connection is an unbalanced BNC jack and the random-wire antenna is, well, a random wire. ;) I have several toroidal ferrite…
Will B - AF7EC
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4
votes
3 answers

What should be in a one hour class about Radios in Boy Scouts

I have been tasked with teaching a one hour class to adults who lead Boy Scout troops about "Radios in Scouting". What should I teach them? Possible subjects include: Teaching the Radio Merit Badge Operating a Jamboree on the Air Use of radios on…
RobSartin
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4
votes
1 answer

Why is 900MHz restricted in some areas in the US?

So I found these rules: (2) No amateur station shall transmit from those portions of Texas and New Mexico that are bounded by latitudes 31°41 ′ and 34°30 ′ North and longitudes 104°11 ′ and …
Skyler 440
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4
votes
4 answers

Low power long distance wireless data communication

I am looking for a communication solution with the following requirements: wireless unidirectional, point to point low power (li-ion battery powered, should operate at least one hour on the single charge) low baudrate data transfer (cca 40 - 80…
4
votes
1 answer

Warbler vs SoundModem

I'm trying to decode a BPSK 1200 (with no success). In this endeavor I tried both SoundModem and Warbler. The scenario here is the following: Ettus receiver + HDSDR with speaker plugged into mic via an audio cable. Warbler and SoundModem both do the…
KcFnMi
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4
votes
1 answer

HackRF One — Expected 'hackrf_transfer -t' file format and its creation?

What file format does the HackRF One expect on the command line, using the -t option with hackrf_transfer? Also, how would I create or convert that format from a standard WAV file? I was expecting the following to transmit a 36 second wav…
M6JNY
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4
votes
1 answer

Why there is no AFSK in FLDIGI

I was expecting to see an AFSK option in the Fldigi "Op Mode" menu (as there is one option for CW, i.e.), why isn't it there? Basically, I want to get the data send according to this.
KcFnMi
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4
votes
2 answers

Is this simple description of SSB correct?

I was recently asked to explain why a "carrier injection oscillator", or CIO is needed in an SSB receiver but not in a transmitter. This is the explanation I gave, and I would be grateful for comments on its validity. I find the usual diagrams…
Harry Weston
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4
votes
1 answer

What is my VE status?

I was an ARRL VE years ago. The info about ARRL VEs says that you remain a VE and the only way one will be dropped is loss of license. However, years ago to be a valid VE one would have to have a current date sticker on one's badge. Am I still a VE?…
Herb Robbins
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4
votes
3 answers

How do I connect a GPS receiver to a radio for APRS?

I volunteer with the local search and rescue group as a team medic and a radio operator. The team is new and recently decided to go with the Garmin 64st as our go-to GPS units. Those of us with licenses use the cheaper Baofeng UV-5R and BF-8HP…
john.weland
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4
votes
1 answer

Correct number of elements in 4nec2 antenna simulation

I am designing a 1.25-wavelength dipole antenna with the 4nec2 software. What I noticed is that the input impedance of antenna is changing greatly when I change the number of segments. How many segments should I choose?
Shiva Mudide
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4
votes
1 answer

Best way for US ham to join RSGB

Overseas hams can join RSGB from their site for 51 GBP, which today is about 79 USD. USA hams can also join through the ARRL for 75 USD. Assuming the $4 is not a factor, are there any advantages to joining directly with RSGB in terms of membership…
James
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4
votes
1 answer

UK Foundation - initial practical assessment, what to expect?

I'm going to be starting the Foundation course in the next few weeks, and have been offered an initial practical assessment at a member's shack to save time for the club during the course. The call to be made is on 2m with a QSY, so I'm wondering…
luxpir
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4
votes
2 answers

What's the unlicensed power limit for 5.8 GHz (5 cm) transmissions?

5.8 GHz NTSC video transmitters are popular for FPV (first person view) model aircraft flying. However, because the 5.8 GHz band (5725 to 5875 MHz) is also available for ISM (unlicensed) use, it's not clear to me at what point I need a license to…
Nick T
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