Most Popular
1500 questions
16
votes
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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16
votes
8 answers
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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16
votes
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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16
votes
2 answers
How does one read a ferrite datasheet?
Datasheets for ferrite materials are usually filled with incomprehensible graphs with greek letters. For example, Fair-Rite's 73 material:
What's a $\mu'_s$ and a $\mu''_s$? What do these numbers represent, and how can I use them in amateur radio?…
Phil Frost - W8II
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15
votes
4 answers
Is a vertical noisier than a dipole, and if so, why?
I've had people tell me, anecdotally, that a vertical is noisier than a dipole. Is this true, and if so, why?
If it is true:
Is this additional noise, such that SNR is degraded, or is the vertical just more sensitive overall, making noise and…
Phil Frost - W8II
- 51,701
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- 88
- 212
15
votes
8 answers
What is the impedance of an end-fed half-wave antenna?
It is my understanding that the feed-point impedance ($Z_a$) of an end-fed half-wave antenna is dependent on at least the following factors:
$L_a$: The length of the radiating element of the antenna.
$D_a$: The diameter of the radiating element of…
Robert Quattlebaum
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15
votes
4 answers
FCC tracking of unlicensed FRS/GMRS transmissions
If a transceiver such as the BaoFeng UV-5R is used to transmit over FRS/GMRS frequencies (unlicensed), it is illegal in the United States due to FCC regulations that state that the power must be <0.5W and that the radio must not have a detachable…
J. Taylor
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15
votes
3 answers
What does Ham mean?
Amateur radio operators are always referred to as Hams, it's basically the most common term for the hobby, at least around here. Where does the term come from? I heard that it's an acronym for something, is that true?
Dan KD2EE
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15
votes
4 answers
Are there federal laws (US) protecting antenna installation?
Are there any federal laws or FCC guidelines that allow ham radio operators to install antennas?
I live in an apartment building in a large city that bans outdoor antennas. I recall reading that the FCC protected the installation of satellite…
Brad
- 265
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15
votes
4 answers
What should I consider when choosing a coaxial cable?
Given a middling-power rig (up to 100 W) requiring a 50 Ω antenna, a few options for the coaxial cable with a 50 Ω impedance are
RG-174
RG-58A/U
RG-8
RG-213
Apart from cost, what factors are relevant in deciding which coaxial cable to use?
VU2NHW
- 2,834
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15
votes
2 answers
If I install a G5RV in my attic how could I be certain there are not harmful levels of RF in the shack, or my kids bedroom?
I assume that anyone who has a G5RV or G5RV junior in their attic has done so with ceramic spacers, and has zigzag or dog-leg installations, or otherwise has contorted the antenna to fit up there.
My worry is how can I satisfy my own and my XYL…
Warren VE3WPX
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15
votes
3 answers
What is a linear RF amplifier?
Most of the RF amplifiers advertised, and most of the questions about amplifiers, are "linear" amplifiers.
What is a linear amplifier, and what other common amplifier type(s) exist that requires people to say "linear" every time they talk about RF…
Adam Davis
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15
votes
1 answer
What is the purpose of a balun and a unun in a feed line?
I have never understood how a balun or a unun works and under which situation I need to use either of them in an antenna feed line.
Dinesh Cyanam
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15
votes
11 answers
Is Morse code a digital, binary mode?
At first glance Morse code looks like a digital mode - there are dits and dahs, two values which contain the information of the transmission. Alternatively, at any point in time there either is a signal, or there isn't.
Morse code follows the…
DK2AX
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15
votes
3 answers
WWV, WWVH, and WWVL may be shut down. Are there any alternatives?
The US government is proposing to shut down the NIST standard time and frequency stations WWV, WWVH, and WWVB in Colorado and Hawaii.
If that actually happens, are there any free or inexpensive alternative frequency standards available so that we…
Mike Waters
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