[ARC5] [BoatAnchors] OK Smart People- FM Demodulator

[Arden Allen]

Dave, if L1-C5 was resonant at the frequency you want to demodulate the
phase shift would be zero degrees, not 90 degrees.  You could think of a
quadrature detector as functioning something like slope FM demodulation with
an AM receiver where you tune the signal to the sloping skirt of the IF
bandpass where frequency variation will produce amplitude variation to the
AM detector.

Arden Allen
KB6NAX

If you get to thinking you're a person of
some influence, try ordering somebody
else's dog around.  -Will Rogers

> ....
..
http://jaunty-electronics.com/blog/2012/08/no-tune-ne602-ne612-fm-demodulator/

It's supposed to work between 420-500 KC.
I'm hoping to "tweak" something like this for 15 MC,
since the NE602 / NE612 will work well into UHF.
What puzzles me is the tank circuit L1 / C5.
820 uH and 100 pF resonate at 555 KC.
Is that right?  And if so, what resonant freq would
one use to get the thing to work at 15 MC?

73 DE Dave AB5S