Motorola TS18

[Zenith26kc20]

I've been working on the TS-18 bakelite on and off for about a year. This set came to me filthy and missing parts. I recapped it and restuffed the electrolytics and replaced the missing parts. The vertical looks full but rolling. The horizontal is too narrow. I would love to hook my frequency counter too the horizontal but don't want to kill it. Same goes for my scope. If anyone has hooked up a scope or counter, please let me know.

[Electronic M]

Originally Posted by Zenith26kc20

I've been working on the TS-18 bakelite on and off for about a year. This set came to me filthy and missing parts. I recapped it and restuffed the electrolytics and replaced the missing parts. The vertical looks full but rolling. The horizontal is too narrow. I would love to hook my frequency counter too the horizontal but don't want to kill it. Same goes for my scope. If anyone has hooked up a scope or counter, please let me know.

Got a 120V isolation transformer to power the TV with? If so that's the recommended solution. Isolation transforms can fail (I found out by feel on an old 50s service transformer a few years ago... Fun!).. Before connecting test equipment measure between the service literature recommended TV chassis ground point and the BNC outter of your scope and or counter with a battery powered DMM... If there's less than 10V AC and DC it should be safe to connect.

Another solution is if you have a spare uninterruptable power supply that can battery back up appliances, plug you scope or counter into the UPS, and unplug the UPS from the rooms wall outlet during measurements. The same DMM check outlined above can be done.

Another thing you can do assuming the RF systems will pass video to screen is find or make a test pattern that'll let you figure out if you're half or double frequency if it'll sync at some multiple. Before I had a scope or counter I did this on a TV that the vertical freq was way off on.

[Zenith26kc20]

Progress! Looking at the schematic and tracing where parts go revealed a missing .03 capacitor missing across the horizontal hold control and the 8200 ohm resistor connected to it!
Now to try and get the fluorescent shop lights off and look for a signal from the agile modulator!

[kvflyer]

I have some parts, if you need them. But please be patient if you request anything.

[Zenith26kc20]

Thanks guys! I'll post a picture of the set tomorrow with a picture of it in sync and a washed out picture. This one has been a challenge but very rewarding. Once I get more video info I'll let you all know!

[Zenith26kc20]

Tried working on it this morning but the intermittent vertical is back and just a white screen.
Never a dull moment!

[Zenith26kc20]

Changing the 6.8 meg plate resistors (the originals were up to 9 meg) and cleaning the tuner (very carefully) and now sound is good even though all 82 ohm resistors in the I F are reading 200+ ohms. I made sure the chassis was connected to neutral and the scope ground was lifted and have no AC across the two.
In doing all this I noticed the red wire on the CRT socket came out of the socket. This is the cathode lead. I put it back and checked the signal on the cathode and have 45+ volts.
Hopefully I can get the CRT installed this afternoon and see what is next!

[Zenith26kc20]

Picture is much better in person than on the camera. But! Horizontal and vertical are working fine! Focus and the I F resistors are next to work on but now I can see this set play. What a wild repair so far>

[ronl]

Looking better!