JC Penney Portable Tuning Help

[demy1942]

Hi Again,
I am onto my next project, just received this tv real cheap and when I received it, unfortunately, the tuning dial turns but the vertical pointer doesn't move. It's one of those things when you turn the dial it just doesn't move the dial. I was wondering about the next step? Just take the machine apart and get to that piece? I will do it this weekend and was wondering about the best way to get this working since I would need this to work to get to channel 3 and the radio stations.

Thanks for helping
demy

I came across this video? If you have something better let me know, really appreciate it
https://www.youtube.com/watch?v=vJeZRrUfYL4

[Electronic M]

There is a dial string in those. If the string is intact the pointer is sliding, if it snapped you'll need to restring it. The antique radio community does a lot of dial restringing. That looks like an RCA portable I had years ago that I have seen labeled as a few other brands.

Something to know the pointer is just an indicator flag...it can be pointed to a completely different channel than the set is tuned to. There should be one or more variable caps and maybe a potentiometer (for the TVs tuner if it is varactor based) inside the cabinet that the string will turn pulleys on.

Dial strings can be a bit tricky and Rube Goldberg-ish....don't open the the can of worms unless you feel ready for something like that.

[demy1942]

Thanks again Electronic. I'll open the case, I should state that the pointer does move about an inch and then no more, I just might have a bum purchase. I wish I knew the dial was like this.

[demy1942]

Hi again, got inpatient, opened the case and moved the round pulley and it was stuck. Now, the pointer moves. However, I then reconnected everything and I get this. Its a black screen with a thin white light in the middle. The tv was working before I opened the case with a picture when I was barely able to get the pointer on channel 3. I did some research, vertical deflection? Looks like something I can't fix? I must have moved something.

I really don't know what to do next and don't want to get shocked, power cord is out when I work on it. What do you guys think? I must have done something.

[old_tv_nut]

First thing is to check if you accidentally disconnected a vertical sweep wire from the yoke. Start at the yoke and trace each wire to the far end to see that they all are connected.

[Electronic M]

Another thing to check is if you bumped the heat sink for the vertical output transistor and cracked a solder joint for the heat sink or transistor.

[demy1942]

Okay, I'll check later, got another TV from goodwill, waste of money

[demy1942]

Hi Guys,

I checked everything and I am not finding the problem. I included a picture, maybe if you don't mind it is on the right side? I went to the library and got a book on this stuff, cool
really thanks for helping out and I would like to get these to work but I am really not qualified with this stuff. By the way, I am working on this stuff, always unplugged, anything else I have to worry about with these small tv's?????

[Popester]

Don't let that line burn in the CRT phosphor. Turn down your brightness and contrast. Look on the underside of the PCB for bad solder connections.