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1500 questions
10
votes
1 answer
CW on phone band
In the U.S., regulations permit CW operations throughout the amateur bands. That makes the phone section of a band look tempting when the CW/digital part of the band is busy with a contest. I wonder if my friends and I can reasonably have our…
Wayne Conrad KF7QGA
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Better explanation for beyond-line-of-sight VHF signal reach than "lower curvature to radio waves"
I am currently studying for the Technician Exam and have come across an answer to a question I think is ridiculous. The question is:
Why do VHF/UHF signals usually travel somewhat farther than visual line-of-sight distance between two…
Dave G
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10
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3 answers
What is the record for the highest non-automated over-the-air CW WPM speed?
Related to this question, but using humans, and in an actual QSO, not lab conditions:
Is there a record for QSO QRQ speed? And, if so, what is the record for the highest non-automated over-the-air CW/Morse Code WPM rate?
And, if so, are there…
hotpaw2
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10
votes
5 answers
What should I do if my call is being used by someone else?
I've been contacted by others who want to verify a DX with me, but I was not operating at that time! It appears that someone made several contacts using my callsign for a short window of time one day.
I've been keeping my ears open, but haven't…
Adam Davis
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10
votes
3 answers
Local phonetic alphabets
In Russia hams use two phonetic alphabets - the regular one (Alpha, Beta, Charlie, ...) and a localized one (Анна, Борис, Цапля, ...). When a ham calls CQ in Russian (which by the way is pronounced not "CQ" but "Всем-всем") she uses Russian phonetic…
Aleksander Alekseev - R2AUK
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10
votes
2 answers
If someone transmits on 151.88 MHz and I listen on 151.18 MHz, how likely would I hear their transmission?
I have a cheap baofeng uv-5r, and I sometimes hear an intermittent transmission which pulses past the squelch threshold with periods of dead space between, roughly 0.75 seconds or less.
My job uses a repeater and radioreference.com lists the used…
Wolfgang Steele
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10
votes
3 answers
Why does ARRL license examination procedure preclude students from discovering what questions they got wrong on licensing tests
I got my Amateur Extra ticket some time ago. I was able to discover what my score was (the number of questions I got wrong). However, my examiner was not able to tell me specifically which questions I had answered incorrectly, and to this day it…
LCS
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10
votes
5 answers
Audio frequency used for Morse code in licensing exams?
Back when Morse code proficiency was required for certain radio licenses, what audio frequency was used by the exam tapes, equipment or examiner that generated the Morse code audio? Was there a legal or recommended testing standard for this audio…
hotpaw2
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10
votes
3 answers
Is it legal to transmit with HackRF one?
Is it legal to transmit using HackRF one (in Germany), the purpose is to do some Lab research and Academic experiments.
for example i want to broadcast an FM signal using HackRF one and try to receive it using another hardware (RTL-SDR).
If no is…
A.SDR
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10
votes
4 answers
Understanding power supply requirements
I have a basic question about power supply requirements for typical transceivers. I'm looking at the specs for a Kenwood TM-V71A, which is a 50W mobile transceiver.
I figured that a 50W transceiver running on a 12V(-ish) power supply would pull…
larsks
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10
votes
5 answers
Are there formulae to calculate capacitance and inductance of an antenna?
How to calculate internal impedance of a dipole antenna? Its resistance has two components ie wire resistance and radiation resistance, both these can be calculated using formula. Are there formula to calculate capacitance and inductance of an…
tgnhbv
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10
votes
5 answers
How did hams manage to tune their antennas before VSWR meters?
In the early 20th century --back when the hobby was still new-- before VSWR meters and antenna analyzers were invented, how did radio operators know whether they were tuned for maximum power out?
This is not asking about antenna tuner design or…
Mike Waters
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10
votes
1 answer
What is Jamboree on the Air (JOTA)?
What does this term mean? I'm not good with radio terms at all, but I was especially curious about this one...
Timtech
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10
votes
2 answers
How do I find a frequency to call CQ on during a contest?
I know that in many contests, sitting on a frequency and calling CQ is a very effective strategy to rack up points. However, during very popular contests it can be very difficult to find an open frequency. How can I find a frequency that I can use…
W5VO
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10
votes
2 answers
Do FCC regulations limit digital data rate?
Are there FCC regulations that specifically limit digital data rate on the amateur bands? Are there any recent or proposed changes? If so, what are they specifically?
Phil Frost - W8II
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