RCA CTC? Table top with rolling cart

[freakaftr8]

What are the odds of this. Last electrolytic needed. I dont have one and it's on order. This could be the cause of my lack of vertical deflection. all orange drops around the oscillator and output stages test reasonable.

This 30uf also is shared with the horizontal oscillator. pin 6. Even though I can't get anything but a Gray raster I can hear the horizontal oscillator lock at the end of the dial.

[Electronic M]

If you have a new 22-47uF of the right or higher voltage rating it is better than an open or shorted cap for medium term troubleshooting purposes.

[freakaftr8]

Well this is looking promising. swapped out a bad 100k on the blue drive pot. Recapped lytics. waiting on 6KA8 and 6KZ8 tuner.

What you are seeing here is the signal pattern generator showing color bars except a bad AGC and a bad tuner tube will not allow for a good signal.

[Electronic M]

Horizontal frequency is off too. You could use a battery or external bias supply to force the AGC line to a better level (alignment procedures often included this practice).

[freakaftr8]

On my BK HV probe, it was off by a mile. Tested it on the Sony KV-2643R. thou HV should be 29kv, it read 20kv. Luckily the probe has an adjustment potentiometer so I set it to what I believe that Sony should be running at 29KV. I tested a few other sets around the house and high voltage on my CTC39 was it 24KV.

On the CTC16, we were at 21kv. I bumped it up to 24kv.

If this high voltage has been running low for quite some time I wonder if this can put undue stress on the fly back. I'm sure I'm answering my own question but I noticed the other night when I ran the set for about 30 minutes the fly back cage felt warm. After I adjusted the high voltage up to 24KV I noticed after a 30 minute run the high voltage cage stayed cool..

My question is, has anyone else had to re qualify a high voltage probe like this with a known good high voltage set So you could use your meter to check other TV's? Is it's a good way to re qualify a high voltage probe?

[freakaftr8]

Inside the probe there is a very long 600 meg Barber Pole yellow and black resistor that was only reading 530 meg. But sure after time and age these things have a tendency to drift.

[Yamamaya42]

Originally Posted by freakaftr8

On my BK HV probe, it was off by a mile. Tested it on the Sony KV-2643R. thou HV should be 29kv, it read 20kv. Luckily the probe has an adjustment potentiometer so I set it to what I believe that Sony should be running at 29KV. I tested a few other sets around the house and high voltage on my CTC39 was it 24KV.

On the CTC16, we were at 21kv. I bumped it up to 24kv.

If this high voltage has been running low for quite some time I wonder if this can put undue stress on the fly back. I'm sure I'm answering my own question but I noticed the other night when I ran the set for about 30 minutes the fly back cage felt warm. After I adjusted the high voltage up to 24KV I noticed after a 30 minute run the high voltage cage stayed cool..

My question is, has anyone else had to re qualify a high voltage probe like this with a known good high voltage set So you could use your meter to check other TV's? Is it's a good way to re qualify a high voltage probe?

which probe you got?

[freakaftr8]

It's a BK precision HV-44

[Yamamaya42]

Originally Posted by freakaftr8

It's a BK precision HV-44

I also have the HV44A, I know about the adjustment to zero the meter, I did not know there was any other, or that it could be opened up to see a big resistor.

[freakaftr8]

Yes if you're looking down at the meter needle it'll be on the handle right side. It's a very small hole that you can insert a flat head into to adjust the calibration.

It didn't take much to move the needle so I'm concerned that excessive jolting around of the probe or possibly a drop could cause the calibration to go out of whack

[Yamamaya42]

Originally Posted by freakaftr8

Yes if you're looking down at the meter needle it'll be on the handle right side. It's a very small hole that you can insert a flat head into to adjust the calibration.

It didn't take much to move the needle so I'm concerned that excessive jolting around of the probe or possibly a drop could cause the calibration to go out of whack

that explains it...

the BK HV44A and the HV44 are not the same.

Mine is newer, all sealed, no adjustments factory calibrated.
https://i.ebayimg.com/images/g/BYYAA...2gE/s-l640.jpg

[freakaftr8]

Interesting.. So I replaced that 6KA8. My assumption was correct. I couldn't get horizontal lock. The control was all the way to one side and needed to go more. I adjusted the oscillator coil. Now I can achieve lock. Left it at the end of the dial. Color oscillator is off freq. Cant lock color. Got splotchy rainbows crawling up the screen. So probably need to adjust the oscillator coil.
My question is why are these so far off? I doubt anyone got in there and messed with them. I've seen other threads about this as well.

Haven't had a chance to go over the IF section for out of tolerance resistors that are known to go flaky but this wouldn't cause the lack of color would it? Isn't this chroma?

[Yamamaya42]

Originally Posted by freakaftr8

Interesting.. So I replaced that 6KA8. My assumption was correct. I couldn't get horizontal lock. The control was all the way to one side and needed to go more. I adjusted the oscillator coil. Now I can achieve lock. Left it at the end of the dial. Color oscillator is off freq. Cant lock color. Got splotchy rainbows crawling up the screen. So probably need to adjust the oscillator coil.
My question is why are these so far off? I doubt anyone got in there and messed with them. I've seen other threads about this as well.

Haven't had a chance to go over the IF section for out of tolerance resistors that are known to go flaky but this wouldn't cause the lack of color would it? Isn't this chroma?

I have this terrible feeling of deja vu

[freakaftr8]

Haha yea. Which one is the color oscillator again? Brainfart... oddly if I go through channels, I have no snow. Just a blank raster. AgC has no effect whatsoever. thinking I might have to go over the IF board a bit.

[Yamamaya42]

Originally Posted by freakaftr8

Haha yea. Which one is the color oscillator again? Brainfart... oddly if I go through channels, I have no snow. Just a blank raster. AgC has no effect whatsoever. thinking I might have to go over the IF board a bit.

A16 is the chroma ref osc coil. Controlled by phase det, via burst amp.
You say you still have blank raster, so there is nothing for the color circuit to lock on to.
In fact, you should NOT be seeing any color at all, color killer should be clamping it down and turning it all off at this point with no video to work with.

i got my test sockets now, so I will be poking around my IF as well this weekend.