I have an older Pioneer VSX-502 receiver that got hit by lightning through the
AC line. Everything seems to work, except for the radio tuner. All fuses are
ok. I have already replaced the LM7001 chip, and the TC9164N (Pioneer suggests
these to be the problem after a strike through the antenna). Still, no radio.

I can get a "thumping" sound (oscillation) through the speakers when in AM
mode, but nothing in FM. Also, there are two indicators in the dislplay for
"tuned" and "stereo". Neither one is lit, except for when the board that
contains the LM7001 chip is removed(?), then they both work, but obvivously no
radio without the antenna card.

One other problem is that when the volume is increased past 1/3 of the way,
there is a relay click (overload protect?), and the speakers cut out. Any
suggestions welcome.

TIA,
Del