Looking for a 1968 Mopar car radio schematic
 

Hi all.
I am looking for a 1968 Plymouth Bendix Mark 1 (284 890)
ser. 9FBBA AM/FM car radio schematic.
Basicly the AM is not working, FM works but not 100% & it also has a split plastic tuning gear. Any Help would be much appreciated.

I bet drh4683 can help with this.

Maybe these photo's may help.

I did unsoldered one pin on one of the resistor/capacitor networks which it brought back the FM to a 100% working condition. You may see the unsoldered pin in PCT0010a.

Some more photo's

Check the Howard W. Sams website. Sams has an auto radio series of schematics. Of course, Sams does charge for these.

Thanks Peverett. E-mail sent.

I would appreciate any other Tech tips.

I did reversed two transistors (dia. A ) with no change to AM or FM. I was hoping if it was a bad oscilator transistor it would show some kind of change.( I.F. would be poor but AM oscilator would tune in?)

There is a diode ( dia. B ) that I pulled & it measures like a diode, but I can not identify. (Zener?) Which lead me to unsoldering Cap/resistor network pin, in turn makes the FM work perfectly.

On the Howard W. Sams website, you can enter the radio model number and see if they have the schematic.

Solved problem
 

I started removing I.F. coils & inspecting the winding in the coils. On the third I.F. coil removed, I found one of the windings corroded, but fixable!

Fixed without any schematics. AM & FM are working!

Now I'll try to fix the broken plastic gear. Any suggestions?

If the gear is otherwise whole, you could superglue it with the proper one for plastics. I used it on a plastic gear in a tape player successfully. If there's room on the side of the gear, sand lightly and superglue thin aluminum "band aids" across the crack.