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  #61  
Old 02-20-2019, 07:21 PM
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Did you check resistors around each IF tube because my sets had several bad resistors around that area. Especially if you think it may be a signal problem.
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  #62  
Old 02-20-2019, 08:16 PM
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Did you check resistors around each IF tube because my sets had several bad resistors around that area. Especially if you think it may be a signal problem.
Yeah, I'd already replaced a few that were double their resistance. Is there a specific way to figure out what section this is emanating from? I've noticed that the power supply has a decent ripple in it, how much is acceptable for a power supply like this?
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  #63  
Old 02-20-2019, 09:02 PM
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It could be, the when the contrast is all of the way up, the picture goes out of control. I'll replace the three that are there. EDIT: I was able to successfully get the picture back to normal by replacing the three capacitors around the contrast control. However, the slight shudder is still there along with the uncontrollableness created by turning the contrast or brightness to full.



Not entirely sure what to look for, however, here's the output of the plate on the sync. Hopefully that helps.

Attachment 198290


I've also purchased a TV analyst for troubleshooting, seems like a useful tool. WOn't be here for another week
That waveform looks pretty messy and weak...See if sams has a waveform and compare. If your sync pulses are messy you will trigger retrace mid line and other troublesome things like that.
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  #64  
Old 02-20-2019, 10:01 PM
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That waveform looks pretty messy and weak...See if sams has a waveform and compare. If your sync pulses are messy you will trigger retrace mid line and other troublesome things like that.
http://www.earlytelevision.org/pdf/m..._rider_tv1.pdf

ETF has the riders which has the waveforms in it on page 30. It's interesting to see that there's a 60hz signal on the sync output, that might explain the jittering. How much of a waveform should I realistically be getting on the power supply? I would have thought that the filter caps being as big as they are would have taken care of it.
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Old 02-20-2019, 10:43 PM
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http://www.earlytelevision.org/pdf/m..._rider_tv1.pdf

ETF has the riders which has the waveforms in it on page 30. It's interesting to see that there's a 60hz signal on the sync output, that might explain the jittering.
There should be 60Hz in the synch output. Vertical sweep IS 60Hz* and it needs 60Hz sync pulses.

*Granted color changed it to 59.9Hz, but rounding is a thing.
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  #66  
Old 02-21-2019, 09:00 AM
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There is a resistor at v1 it's a 1k with b+ at the one end, just from my troubles with my sets double check that resistors value because I have had that resistor bad and even burned up.
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Old 02-22-2019, 02:41 PM
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Checked that, however I just realised that some of the caps that I installed in the horizontal are 500v mica caps when it calls for 2kv caps. That might explain a little of that. The two caps are C71 and C72 680pf and 900pf respectively. Do those need to be mica caps or can i use ceramic discs?
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  #68  
Old 02-22-2019, 03:46 PM
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No don't use ceramic, and as for the voltage yes the cap may show 2k volts but the 500 volt works fine since all the Micas even the ones in the sweep section are 500 volts that I put in my sets and my sets work great with them. I don't think 2 k Micas are available anymore. To answer your question yes Micas belong in that section, the schematic shows mmf , that would be the Micas.
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  #69  
Old 02-22-2019, 05:31 PM
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Do you have the high voltage cover in place? It can cause issues if it's not installed.
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  #70  
Old 02-22-2019, 08:19 PM
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Do you have the high voltage cover in place? It can cause issues if it's not installed.
Yes, it's in place, I messed with it and the picture got worse so I think it's making a good connection to chassis.
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  #71  
Old 02-23-2019, 11:24 AM
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Does the distortion of the picture slowly move vertically with respect to the picture? If it does, the source is likely 60hz power related, which is not quite in sync with the vertical frame rate.

jr
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  #72  
Old 02-23-2019, 06:20 PM
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There is a high voltage filter capacitor to chassis ground which is a .001 6kv , was that one changed. It may or may not effect the quality of the picture but you never know. Can you at all figure out weather or not it's verticle or horizontal, it would help things a lot at this point. Just a crap shoot but there is a mica that is usually mounted under the terminal strip where the .01 caps are for the verticle and if it's under there it is well hidden and that one should be changed as I had lots of problems and found that one hiding under there and that cured the headache I had with one set I have. Just trying to toss things out there.
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  #73  
Old 02-25-2019, 03:45 PM
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I'm thinking it's more some sort of external signal. For now I've put it back in the cabinet and I'll recheck it. One question though. Since this is a transformerless set, I assume the chassis is hot during operation right? and would justify a polarized power cord?
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  #74  
Old 02-25-2019, 03:54 PM
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I'm thinking it's more some sort of external signal. For now I've put it back in the cabinet and I'll recheck it. One question though. Since this is a transformerless set, I assume the chassis is hot during operation right? and would justify a polarized power cord?
It wouldn't matter...
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  #75  
Old 02-25-2019, 04:10 PM
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Oh, ok, nevermind then, I wasn't sure because I had measured line voltage from chassis to wall ground. Any reason for that?
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