Motorola TS-4J

[Zsuttle]

Originally Posted by bandersen

Definitely do not connect anything to the chassis.




Ah, that's weird. What caps do you mean exactly? There are two electrolytics in the audio circuit and neither goes to B++.

If you mean the 20uF cathode bypass on the audio output tube, it should only have about 9 volts across it. Perhaps that 25L6 has a short or is miss wired ?

The other is a 10uF in the FM ratio detector that should only have a few volts across it as well.

Ah, my mistake, I glanced at the A and assumed it was from the power supply when I was looking things over.

Originally Posted by EdKozk2

Your right Bob, I didn't catch the top symbol you circled for ground, Sams' had their own notation. With the correction you noted, then leaves some of the filament bypass caps in the set incorrectly grounded. I'm using the Wallaces' Motorola book which show C-18,24,27,28,33,79 and 80 to chassis ground. I used sams folder 71-12 to cross check. Zsuttle should probably use the riders schematic from the ETF. It would probably be more accurate.
Ed
I did some more checking today, it seems the ETF Riders schematic for the TS-4J is for the early version. I added a picture of the schematic for the late version power and filament supply.

I see that the SAMs has a few mistakes. Where can I get the full schematic from? I'm still tracing out the power supply using the new schematics and all. Also, just wondering what's the difference between the Late and Early versions?