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Old 28th Jul 2022, 5:41 pm   #164
regenfreak
Heptode
 
Join Date: Nov 2018
Location: London SW16, UK.
Posts: 534
Default Re: 6-gang FM stereo tuner heads

I have tested the Nelson Jones's IF and detector circuit. It works OK but it does not sound that great. My homebrew valve IF strip is staggered tuned and it sounds great at the expense of poorer selectivity.

I use 10.7MHz Toko IF transformer from ebay as the quadrature detector coil for the TAA661B chip. It gets lots of distortion if the coil is not fined tuned at its sweet spot. Maybe the audio quality gets better if I change its 4.7k resistor across the tank circuit...anyway I am going to try LA1222 IF chip based on the IF stages of the Kenwood KR-9600 (1600Watts per channel, I mean who can play that level of output power before the neighbors complain and police turn up at your door step)
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