Pioneer Tuner F-Z460L strange problem

[Stefan Toftevall]

Hi guys,
I recently had one of those Pioneer tuners came in my shop with a
strange problem. It can work properly for two weeks or so, then audio
is completely muted. When it fails, I can see there are no output from
the demodulator ic LA1265, so I guess the aftercoming stereo MPX
DEMOD.ic, AN7470 is OK. Could the problem be the standing front-end
module? Is there anyone who had such problems before with this tuner?
Of course, If the stereo MPX ic is loading the '1265 excessively it's
audio will be muted aswell. Any hints is appreciated!
Best regards
Stefan

 

[Mark D. Zacharias]

I had a bad detector coil on a similar Pioneer recently. Grabbed one off a
scrapper - end of problem. It looked like a little RF transformer with a
small crystal shrink-wrapped to it.

Mark Z.