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5 questions from the last 7 days
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Capacitance between two parallel wires with a cylinder of a dielectric added
A open twin feeder or a Lecher line is two parallel wires, both the inductance per meter and the capacitance per meter affect the impedance and the velocity factor of the line. While the polythene of ...
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How to match 5w radio output to 0.005 watt input on amplifier
Found a 50-ish watt amplifier kit online that looked like a good challenging build.
It says it provides 40dB of gain, and specifies maximum input power of 0.005 watts.
The candidate radio I'd like to ...
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Reverse protection for PA
I am designing an RF transceiver for TX RX at 435MHz. I have the module working fine without any issues with PA TX at 2W.
The only issue is the reverse power from the antenna if both units are placed ...
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Hopelessly Lost on BFO Island
I am picking up some low ssb somewhere I think on the 160meter band (1800 -2000 khz) on one of my homebrews. I can also pick up much higher ssb bands, but this low stuff I was concerned because I ...
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What is this signal?
https://drive.google.com/file/d/1pCUDjJbDJVGmmnhp-jYk_vXjfm_KxK6V/view?usp=sharing [18kb .m4a file] (Note: The file was edited to remove the 30 seconds of silence between bursts.)
Heard on 7-May-2025 ...
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