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1500 questions
9
votes
6 answers
Aluminum vs copper antenna element lengths
Does the particular metal used in antenna elements make any difference in element length or spacing, i.e. 1/2" aluminum tube vs 1/2" copper tube?
I know that length and diameter have an effect on resonance and impedance, but does the particular…
David Thorpe
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9
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2 answers
Why is this requirement in 60m in the US?
According to the FCC, if you are using an antenna other than a dipole, in 60 meters, you must keep a record of the transmission and gain of the antenna.
I don't remember seeing any other requirement of log keeping. Why does this one exist? What's…
Pablo Fernandez
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9
votes
1 answer
What is a waterfall display?
High-end transceivers apparently come equipped with a water-fall display - something to do with improved spectrum visibility. This is supposed to lead to potentially higher QSO count and rate.
What is a waterfall display?
VU2NHW
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9
votes
3 answers
What is the electrical shock risk of an antenna?
I've seen people refer to avoiding touching an antenna or bare transmission line that might be transmitting. What voltage potentials and currents are commonly found on typical ham radio antennas? Do both the voltage and current increase with…
Adam Davis
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9
votes
1 answer
Around the world propagation?
Is it possible to transmit a signal around the world and receive it? Has anyone done it, and how? If not, how could this be accomplished? Assuming a complete path around the world, what kind of time delay should one expect on their transmission?
Adam Davis
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9
votes
7 answers
When and why does the size of a ground plane or radials matter?
Consider these three cases:
My understanding is that when building or installing an antenna designed to operate over a ground plane (e.g. a quarter-wave vertical), the size of the ground plane does not matter (e.g. the earth, possibly coupled using…
Kevin Reid AG6YO
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9
votes
2 answers
How do sunspot numbers (SSN) affect radio operations?
I frequently hear talk about SSNs in Amateur Radio, and somehow if the number is high, that's a good thing. I just don't really understand what they are, and what they mean, and I'd like to better understand them. What is the big deal about SSNs,…
PearsonArtPhoto
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9
votes
5 answers
Can a Baofeng UV-5R Display Both Name and Frequency Simultaneously?
The Baofeng UV-5R style radios have a 2 line display that can display the Name, Frequency, OR Number of the selected memory location for each of 2 memory locations.
Is it possible to display the Name AND Frequency using both lines for just one…
Lance
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9
votes
5 answers
Home-brew 10 meter walkie talkies?
"When I was in high school, we had 8 hams at once. (Probably rare) 4
of us built little 10 meter walkie-talkies and had great fun using
them on Field Day, hiking or around town. It was especially fun
because this was pre-cellphone and…
Skyler 440
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9
votes
5 answers
Why do some straight keys have a slider that shorts the contacts continuously?
I ended up with an old straight key that has a curious feature: below the main arm that you would tap on, there's an extra metal flange that can sort of loosely pinch an extra sliding lever underneath, basically like a knife switch tipped…
natevw - AF7TB
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9
votes
2 answers
Does a balun need to be made with coax?
The short version
My understanding is that one of the main reasons to use a balun with coax is to prevent the outside of the shield from becoming part of your antenna system. If that's the case, won't a design like the one pictured below be…
Dominick Pastore
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9
votes
2 answers
How does the South Atlantic Anomaly affect propagation in the HF bands?
At ~34ppt the Southern Ocean is significantly less saline than other major water bodies (Arctic Ocean excluded). The Southern Continent also shares proximity to the South Atlantic Anomaly - where the Earth's inner Van Allen radiation belt comes…
VU2NHW
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9
votes
2 answers
Cleaning relay contacts?
I have an old transceiver. I have a problem where ocassionally the received signal will drop out when switching from transmit to receive. I've narrowed it down to the transmit/receive relay. When bench-testing the relay, it "clicks" over to receive,…
Dan KD2EE
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9
votes
2 answers
How are multiple-operator contest stations with one radio usually operated?
I am the president of a small school club. We plan an participating in the ARRL SSB Sweepstakes this weekend, which is our (new) club's first real multi-op contest effort.
How do multioperator/club contest stations with only one transceiver usually…
krzysz00 KF5SOQ
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9
votes
1 answer
What happens if a station did not submit a contest log?
What is the result of a contest station not submitting a log for the contest? Are all the contacts nullified for the other stations that contacted him? Is it bad form for a non-participating station to contact stations that are participating in a…
Joe Cotton
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