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  #46  
Old 03-20-2017, 03:37 PM
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The .1 is actually at both but separated by the 2.2 or 3.3 the resistor off the vert hold pot.
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  #47  
Old 03-20-2017, 04:01 PM
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duplicate... ignore
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  #48  
Old 03-20-2017, 04:02 PM
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Take another look at the schematic... I see no connection between C-63 (.1) and the 3.3 meg resistor (R-57) that goes to the vertical hold pot.

How are you testing the caps?

jr
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  #49  
Old 03-20-2017, 05:20 PM
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The connection is there where the vert hold and size pots are connected via resistors it's under the tie strap it goes to the vert oscillator . I have a Dvom that checks caps but does not apply any voltage to simulate actual in circuit operation.
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  #50  
Old 03-20-2017, 06:26 PM
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I don't see a connection on the schematic. I urge you to look at the schmatic and compare it and the wiring in the area of these two pots.

The cap may very well be leaky at operating voltage... Dvom measure of value only will not indicate that problem... if you have an old cap in that location, replace it, and any other old caps in the vertical sync, osc and output circuits.

jr
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  #51  
Old 03-20-2017, 06:53 PM
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Quote:
Originally Posted by jr_tech View Post
I don't see a connection on the schematic. I urge you to look at the schmatic and compare it and the wiring in the area of these two pots.

The cap may very well be leaky at operating voltage... Dvom measure of value only will not indicate that problem... if you have an old cap in that location, replace it, and any other old caps in the vertical sync, osc and output circuits.

jr
I am aware that my meter won't check it in operating time so I will be subbing a few caps to maybe weed out a possible bad one. So I checked and good point my mistake it was not separated by the resistors I checked the schematic and it's all in place. Thing is first time on I had vert then it was gone so it may be a cap I hope. And there are no old caps left all changed and also all the Micas in the verticle and horizontal.
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  #52  
Old 03-21-2017, 05:24 PM
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Well still no luck here as I subbed all the key caps for verticle and no change i am wondering if the verticle centering could screw all of this verticle up the way it's doing although the vert centering does move up and down but don't know if this could be the cause. I would rather know if this may be it befor changing it I found have a spare.
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  #53  
Old 03-21-2017, 05:30 PM
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Maybe your problem is further back. Have you gone over the sync circuit ?
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  #54  
Old 03-21-2017, 05:44 PM
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Yes I went over the SAMs and it all looks good sync v11 and at the 6sl7 and between the both, caps and Micas. I have never had something like this after going over what seems like everything and not finding a problem I thought it would have been obvious. If the vert centering pot goes bad being there is hv running past it would the ohms go down in value rather then up, a kind of carbonizing ?

Last edited by timmy; 03-21-2017 at 06:20 PM.
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  #55  
Old 03-21-2017, 08:42 PM
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This may sound like cheating, but on my VT-71 when one axis of deflection was running off frequency I got out my cap decade box and played till I found I could add capacitance in parallel with a stock cap to get it into sync range. It worked and I've not looked back...It makes a decent last resort.
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  #56  
Old 03-22-2017, 05:24 AM
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Quote:
Originally Posted by Electronic M View Post
This may sound like cheating, but on my VT-71 when one axis of deflection was running off frequency I got out my cap decade box and played till I found I could add capacitance in parallel with a stock cap to get it into sync range. It worked and I've not looked back...It makes a decent last resort.
It makes no sense there is a problem like when I parallel the .004 cap with a .01 it seemed to work but not perfect but now with the right hv caps that trick don't work anymore but I did parallel caps and I just cannot get it.
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  #57  
Old 03-22-2017, 01:36 PM
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Ok resistance checks on 6sl7 and 12sn7 sync tube are actually perfect according to SAMs.
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  #58  
Old 03-22-2017, 01:40 PM
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Very much a long shot, but have you tried another CRT that is known to be good?

jr
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  #59  
Old 03-22-2017, 02:05 PM
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Quote:
Originally Posted by jr_tech View Post
Very much a long shot, but have you tried another CRT that is known to be good?

jr
yes I tried another crt same thing. But I did a resistance check on the horiz v13 and all pins are perfect except for pin 2 unless SAMs is wrong but it shows that what should be there is 20k-520 ohm but I'm getting 2.223k so this is not right . There is the horiz afc and block oscillator trans that pin 2 leads to one of those trans and I checked the resistors on both transformers one in the can and the one at the other trans and both are good .
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  #60  
Old 03-22-2017, 02:21 PM
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See post 31 and 32 in this thread... does the measured resistance at pin 2 of V-13 change when you vary rhe horizontal sice control?

jr
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