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1500 questions
10
votes
3 answers
Is it legal for a non-profit to use ham radios for emergency purposes?
I've been tasked to help update my organization's emergency contingencies and ham radios were brought up. We provide residential services to the mentally handicapped and we are looking at ways to make sure the staffed houses can talk to each other…
Michael Ramirez
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10
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5 answers
I can copy 15wpm how to to continue?
I solely learned to copy cw via a computer program using the Koch - method
(http://f6dqm.free.fr/soft/cwplayer/en/cwplayer.htm)
I never learned how to send and if it is no big disadvantage, I would prefer to learn this at the end, when I am…
03525
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10
votes
3 answers
Can a 1:1 transformer be used as a protection from static electricity?
It's well-known that under certain conditions verticals and dipoles can gather static charge, which is a common reason of transceiver damage. There are several ways to solve this issue. Some hams suggest to place a 100 kΩ high-power resistor to the…
Aleksander Alekseev - R2AUK
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10
votes
3 answers
Why prefer LC oscillators rather than RC oscillators in RF design?
I don't recall ever seeing an RC oscillator driven RF transmitter or receiver.
What prevents people from choosing RC oscillators in RF design?
Adam Davis
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10
votes
2 answers
What is the expected microphone input voltage level of a handheld transceiver?
Ok, so I'm looking to inject some computer generated CW into a little handheld rig by wiring direct into the mic input line. What sort of voltage is expected on this input, are we talking uV, mV or even Volts?
user521
10
votes
2 answers
Grounding VHF base station antenna
I'd like to install an outdoor dual band VHF/UHF base station antenna, a simple pole antenna like the Comet GP-1.
I live in an area where lightning is rare, but not unheard of. Should I drive ground rods into the ground for antenna/RF grounding? The…
Johnny
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10
votes
3 answers
Calculating Doppler Shift for satellites
If I know how fast a satellite is moving through space, how can I calculate the doppler shift for the pass?
Skyler 440
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10
votes
3 answers
Do I need to actually lock up my station?
Per §97.103, one is responsible for the proper operation of one's station, which of course includes that no unlicensed person uses it to transmit.
I have heard suggestions (no link handy, sorry) of taking actual physical security measures such as…
Kevin Reid AG6YO
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10
votes
2 answers
What is meant by "poles" when discussing filters?
I was looking over the product page for the K3 (dreaming I know) and noticed that they offer a variety of crystal filters. Some are 5-pole and some are 8-pole, other than price, what is the difference and what is meant by "pole" in this context?
WPrecht
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10
votes
2 answers
Scoring quality of Morse Code "fist"?
When learning, teaching oneself, or training a class in Morse Code sending using a hand key, how can acceptable quality be scored (other than the letters being correct terms of dot-dash sequence)? There a big difference between the dots being a bit…
hotpaw2
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10
votes
1 answer
What Part 97 rule allows unattended, automated transmissions, such as APRS weather stations and beacons?
What rule allows Amateur Operators to establish and operate remote, automated stations like APRS weather stations or beacons?
Are there different rules specifically for beacons, or do they all fall under the same rules?
Adam Davis
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10
votes
3 answers
What is the difference between FCC station and operator licenses?
I an studying for my technician class examination, and I came across this question:
What may result when correspondence from the FCC is returned as undeliverable because the grantee failed to provide the correct mailing address?
A. Fine or…
KQ4JWT
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10
votes
4 answers
Why are there so many coaxial cable impedances?
Why do we have 50, 75, 62 and 92 Ω coaxial cable, to name a few? Why not just one standardised cable? Is there some technical reason or did Mr. Coax and Mr. Cable have a disagreement, like Mr. Tesla and Mr. Edison?
R Johnson
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10
votes
1 answer
What does a lightning bolt symbol next to an antenna connector mean?
On the back of my Yaesu FT-897, next to each of the antenna connectors, there are lightning-bolt-ish symbols. What do these mean, and is there something I ought to be doing because of that?
I have not found any description of a meaning for these…
Kevin Reid AG6YO
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10
votes
2 answers
What is the most common amateur identification practice for mobile US amateurs operating in Canada?
When a US Amateur operates in Canada, IT and Canadian regs permit some lattitude on their identification. I have read that some will prefix a "VE3" plus their own home callsign (Ontario, meaning I am in Ontario right now, but my real callsign is the…
Warren VE3WPX
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