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1500 questions
19
votes
6 answers
What defines music, per amateur radio regulations?
Sometimes when I access IRLP nodes, they have a very short melody telling you that you are connected; or when my local repeater's net begins, it does the famous doorbell 8-note sequence. What is the fine line of prohibited and allowed with respect…
Skyler 440
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19
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5 answers
FCC sends "Notice of Dismissal" with quite threatening language just for denial of a vanity callsign?
I had applied for a vanity callsign which wasn't available. That was in March. The FCC license system shows my old callsign is still in effect.
Today, after a longer absence from my mail, I open a "Notice of Dismissal" which says in a wordy way lots…
Gunther Schadow
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19
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5 answers
What do "QRM" and "QSB" refer to?
An answer on Basic QSO format? mentions things like "QRM" and "QSB". What do those terms mean?
Amber
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19
votes
3 answers
Why do amateur radio operators call an RF choke a balun?
When using a balanced antenna such as a half wave dipole, with an unbalanced feed line such as coax, an RF choke can be used to block RF current emitted by the transmitter from splitting up at the antenna feed point and traveling along the antenna…
Andrew
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19
votes
6 answers
Using a Morse code key with a computer?
Are there standard ways to connect a hand key (straight or paddle) to a contemporary computing device (PC laptop with no parallel port, Mac, Android, iOS device, etc.) for developing or improving ones Morse code sending skills?
If so, can one use…
hotpaw2
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18
votes
1 answer
How does an SWR meter really work?
For ham radio operators, the SWR meter is a ubiquitous piece of equipment. There are dozens of standalone models on the market and most modern transceivers and antenna tuners have this functionality built in.
Any ham with an interest in antennas has…
Glenn W9IQ
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18
votes
2 answers
Is there a disadvantage to using a cheap HT for APRS?
Looking to build a cheap (not even inexpensive, just dirt cheap) APRS beacon transmitter. Right now you can get a dual band handheld transceiver with rechargeable battery, antenna, etc for under $31 [USD], for instance. I can't find a cheaper…
Adam Davis
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18
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4 answers
Where are the baluns for VHF and higher? How can one be made?
In another question, commenters recommended that I look into adding a 1:1 balun to a dual-band dipole to eliminate the feedline as a radiator. As I understand it, a 1:1 balun also functions as a choke, but is more efficient because... reasons?
When…
William
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18
votes
3 answers
What is a "random wire antenna"?
Some antenna tuners claim to match any “random wire” to any HF frequency. Can one really use a random wire as a practical antenna system?
From everything I have heard, the resonance of the antenna (length, material) is what defines its performance…
Ron J. KD2EQS
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18
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9 answers
Is packet radio possible on Baofeng UV-5R and similar HTs?
I am curious to know if it is possible to do packet radio on VHF/UHF using the UV-5R... I have seen some invasive hardware hacks, but without modifying the radio itself (firmware, hardware) it's my understanding that you can only toggle send/receive…
user400344
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18
votes
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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18
votes
5 answers
Can a licensed ham use or modify CB equipment to work the 10 Meter Amateur bands?
Can a licensed ham use or modify CB equipment to work the 10 Meter Amateur bands? If so, are there any advantages/disadvantages to this?
Timtech
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18
votes
2 answers
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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17
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3 answers
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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17
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2 answers
Why do repeaters use cavity filters?
Repeaters apparently often use large, expensive cavity filters to connect the receiver and transmitter to the same antenna.
Why aren't typical electrical circuits, such as inductors and capacitors used instead? Wouldn't they be cheaper and smaller?
Adam Davis
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