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Old 01-21-2017, 08:33 PM
Findm-Keepm's Avatar
Findm-Keepm Findm-Keepm is offline
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Join Date: Jun 2007
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We used a similar setup in the Navy to check center frequency on TACAN flightline test sets and 243MHz Emergency beacons. Both were swept frequency output, making a freq counter unusable, so we heterodyned/down converted the output with another frequency (offset by 10-60Mhz). Both went into a simple diode mixer, and the difference was either displayed on a scope, spectrum analyzer, or fed to a frequency selective voltmeter.

Very common usage back in the 50s-70s, before GHz-capable spectrum analyzers, scopes with 500MHz (+) bandwidth, and DSP filtering.

Cool to see the setup for TV IF Sweep!

Someday I'll get the gumption to do your VA62 mod, haven't the need for it yet.
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Brian
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CET- Consumer Repair and Avionics ('88)
"Capacitor Cosmetologist since '79"

When fuses go to work, they quit!

Last edited by Findm-Keepm; 01-21-2017 at 08:49 PM.
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