I found a nice crystal frequency on eBay : 10.6875 MHz
Yes, 10700 - 12.5 kHz.
Combined with a 15 kHz wide 10.7 MHz FM filter and a direct conversion receiver this should make a 10.7 MHz spectrum scope with 15 kHz bandwidth, so :
10.7MHz signal from R7000 or similar receiver -->
possibly a preamplifier, in any case some termination for the filter -->
10.7MHz FM filter for 25kHz channel spacing (BW = 15 kHz) and 2nd termination -->
DC-mixer with oscillator frequency of 10687.5 kHz (possibly pulled up to 10690 kHz) -->
AF amplifier -->
output to PC running spectrumLab
Looks like yet another 'little' project.
should be good for looking at satellite transponders with (not too wideband) digital signals, and some Doppler tracking at the lower satellite frequencies.
"The Art of Electronics" #8 -- Why Not a Simple Emitter Follower as The AF Output Circuit?
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Click on the image for an easier read
*Back when Dean KK4DAS and I were trying to find a suitable AF amplifier
circuit for our High School Direct Conversi...
3 hours ago
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