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N0ZYC 90dB FSM:




I found an inexpensive wide-range LED field strength meter (FSM) module online, and built a simple meter box
around it. It's got nine LEDs (plus a power LED), that should range from -70 to +10 dB. It's not tuned,
and certainly doesn't distinguish from other transmitters, so it might be tricky to use if there are several
foxes placed close to each other.

Since this is a wide-band receiver it can pick up emissions from other bands and even EMI. I found that a
bandpass filter works to reject other emissions and just display field strength for signals in the 2m band.
Unfortunately they're rather pricey, and this one cost more than my meter. But it can easily be moved to
another meter.



500MHZ field strength meter ($20 at eBay)


FPB-144 2M band-pass filter (in band filters)

A listing 1	A listing 2	B parts and measures	C cut and drill 1	C cut and drill 2	D fit test
E test assembly	F smoke test 1	F smoke test 2	G glued 1	G glued 2	H assembed 1
H assembed 2	I top 1	I top 2

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