Cr-820 FM tuner weak reception

I've got a CR-820 with an odd issue. The FM acts as if there is no antenna, it will receive stations very faintly with loads of white noise throughout the dial but the reception is extremely weak and no amount of antenna does anything. I have verified that there is no break in any wire going from the FM board to the antenna terminals. It seems to me possibly an RF amplification stage is dead maybe? Bad osc coil? Mega out of alignment? Bad cap somewhere? I do not know a whole lot about FM tuners.

As a last resort, I have a second CR-820 with a blown channel that I can swap the tuner board over to, but I'd rather repair the second 820 and save it if I can fix the tuner in this one.

Near impossible to find that without test equipment unless it's something visually obvious. Check the power supply voltages first. Could be a popped front end FET/transistor or bad IF amp. It probably isn't alignment unless somebody already messed with it. Where are you?

I'll check the power supply voltages to the tuner, and check the front end amplification stages. I don't think anyone's messed with the alignment- at least I hope not. If anything I have a working 820 tuner section to compare measurements to. I can scope stuff out if I need to..
Im in indiana btw!

First things first...what sort of antenna are you using? My CR-820 has no tuning issues at all but it does not like powered antennas. It much prefers dipole antennas.

Yamaki said:

First things first...what sort of antenna are you using? My CR-820 has no tuning issues at all but it does not like powered antennas. It much prefers dipole antennas.

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Just a regular wire, nothing powered. Now that I think of it.....I think that this particular receiver was having issues cutting on and off, and the voltage regulator transistor had some bad solder joints... I seem to recall fixing that issue and then forgetting to screw the middle chassis bracket back down and it slid....I may have shorted something out in the tuner...where do I start looking?

Btw, just got a hp FM sig gen, and a hp distortion analyzer and dc null meter.