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Old December 2nd 09, 01:58 PM posted to rec.radio.amateur.homebrew
Tim Shoppa Tim Shoppa is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 263
Default 3:1 range VCO and varactor RF voltage swing

On Nov 29, 9:07*pm, lw1ecp wrote:
Raypsi:
- Thank you for the hint, the CATV tuners cover 54 to 900 MHz (5 to
~40 is for the upstream), an impressive 16:1 range, but the L.O. is
much narrower in relative values. Suppose 1st IF at 1200MHz, the L.O.
would sweep 1254 to 2100, 1.67:1, not enough for me.


I think maybe you're looking at the wrong generation of CATV tuners. I
think Raypsi's suggestion was for the little tin-can tuners common in
say 80's and 90's VCR's, these certainly did NOT have a 1200MHz IF,
closer to 45MHz.

Tim.