Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

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1500 questions
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2 answers

Why is the solar-flux index measured at 10.7 cm?

Why is the solar-flux index measured at 10.7 cm? What makes that such a special frequency?
Dan
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3 answers

Why are proprietary codecs used in amateur radio?

This may be slightly off topic (maybe there's a Legal Stack Exchange :-D), but how is it that codecs like Yaesu's C4FM are allowed to be proprietary while still being used on Amateur bands? At the very least, this does not seem to be in keeping with…
Joshua Nozzi W4JLN
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8 answers

Should I chose a vertical or a horizontal HF antenna?

If I only have the budget for one HF antenna, should I chose a vertical or a horizontal antenna?
Timtech
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If I receive an SOS signal, what is the proper response?

My 5-year old son loves sending out an SOS signal using a toy Morse code generator (wired, don't worry about false alarms for real authorities). He has learned to send the SOS signal and was asking me to send a response to him to let him know that…
Hanky Panky
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17
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4 answers

Understanding coax impedance

I keep doing research, and trying to grasp it, but when it comes to RF impedances, and coax, I still have trouble trying to grasp it. So first, I think you have to have a 50 ohm coax for a 50 ohm transmitter to keep the impedances matched. I think I…
Skyler 440
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What does a noise blanker really do, and what are the side effects?

Most HF rigs have a noise blanker (NB) feature. It does reduce some types of noise (car ignition noise and such). How does it really work? I've read it has negative side-effects with strong signals, which is why it is not enabled all the time.
oh7lzb
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16
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What's wrong with 220MHz?

It seems like 220MHz is the bastard step-child of the amateur world. Every HT is either 2m or 2m/70cm. Some companies offer tri-banders, but they almost always add 6m (?!), not 220MHz. The only way to get this band easily is the Chinese radios. I…
WPrecht
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7 answers

What is the cause of this unusually long period of terrible HF band conditions?

I've been a ham for over 40 years, but never has there been such a prolonged period of such poor propagation. This has been especially the case over the past six months or so, and they continue to deteriorate. What could possibly be the cause? This…
Mike Waters
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13 answers

How can I safely transmit without an antenna tuner or SWR meter?

Just what the title says. An Antenna Tuner, henceforth AT, is almost a de facto piece of equipment in a shack; working the bands without one is tantamount to leaping off the diving board into a swimming pool with tarantula nests in it ... or…
VU2NHW
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What bands and modes will give me voice at 3,000 miles?

I pursued Amateur Radio primarily for local emergency communications and as part of my electronics education. My only radio right now is an inexpensive 2m/70cm HT which is good for local weather spotting and emergency operations. I'm interested in…
Adam Davis
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How does selecting the opposite sideband when receiving CW on HF reduce interference?

I am studying for my FCC General Class license, and question/answer G4A02 reads as follows: Q: What is one advantage of selecting the opposite or "reverse" sideband when receiving CW signals on a typical HF transceiver? A: It may be possible to…
Bryson
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16
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4 answers

OK to use any repeater?

There are a number of repeaters in my area, each belonging to a particular amateur radio club. These guys are all friendly and willing to chat but I was wondering if it was bad form to make use of a repeater belonging to a club you aren't part of…
s3c
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6 answers

Where can one find recordings of Morse code, generated by humans and not machines?

I need some recordings of CW / Morse code for use in a project. Most of what I find is either nonsense (it just exists for the 'sound of CW', but doesn't contain a message) or is generated by a computer. Where can I find some audio of real CW…
Ken - Enough about Monica
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Are there any real advantages to an aftermarket NA-701 over the Baofeng stock antenna?

I have a Baofeng UV-5R HT radio that I have been using for about a month now and I really like it because it was very inexpensive and portable. It currently has the stock antenna on it and I have noticed that if I'm in more rural areas, I sometimes…
StompinFlax
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4 answers

Does a FCC amateur license cost money?

If I wanted a FCC Amateur license, is this going to cost me anything? That includes tests, application fees, filing fees, and anything else but hardware.
AwesomeUser
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