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Old September 14th 06, 12:12 PM posted to rec.radio.shortwave
N9NEO N9NEO is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 181
Default Degen DE31 'portable' Shortwave "Active" Loop Antenna

More thoughts on the placement of the variable capacitor

- A parallel resonant circuit has fairly large currents sloshing back
in forth between the caps and the inductor. Of course in a loop
antenna arrangement where we are dealing with microvolts the currents
aren't so large, but, any resistance in the path (such as a long thin
cable) between the inductor loop and the variable capacitor will reduce
the circuit's Q. So an arrangement using a potentiometer by the user
and a varactor diode by the loop end is perfect.

Regards,
Yzordderrex