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  #61  
Old 06-01-2018, 10:19 PM
Wind157 Wind157 is offline
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So I've replaced the capacitors in the can and the image is still off. The top of the image seems to be above the viewable area. When I adjust the height the bottom two inches compact and are black. When I adjust the vert lin it goes to a flat line or with the old cap it wouldn't change at all just compress/cut off the bottom.
Is the all just the nature of this type of set getting a feed that nots meant for this screen?
Then there is the matter of the small gap in image on the left side.
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  #62  
Old 06-01-2018, 10:38 PM
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IIRC you have not replaced the bumblebees and tubular ceramic caps in that set yet...Vertical troubleshooting 101 replace EVERY cap in the vertical stages first (no exceptions, total original capacitor genocide!), check for proper operation, then go after tubes and resistors.

See all the caps circled in my edit of your picture? If any of those are in the vertical stage or any vert capacitors currently installed look like them then the vertical will probably not work completely right.

Lytics can cause problems in the vertical (and sometimes are the only problem), but papers can be as bad or worse. On a set this old it is a miracle it works as well as it does now with those lousy old caps.
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Last edited by Electronic M; 06-01-2018 at 10:50 PM.
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  #63  
Old 06-01-2018, 11:45 PM
Wind157 Wind157 is offline
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I already have all those marked for replacing but thanks.

Guess I'll see how it appears after that. I suspect it will be the same. Which if it is then so be it, could be far worse for a free set that's 61 years old
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  #64  
Old 06-03-2018, 10:34 PM
Wind157 Wind157 is offline
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So I've replaced the caps and it actually preforms worse? The screen height issue is still an issue and now the screen flickers consistently.
I'm going back to the old caps before I stick more money into this.
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  #65  
Old 06-03-2018, 10:39 PM
Wind157 Wind157 is offline
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Unless I'm reading the can wrong. I'm assuming the prong in the upper right corner to match the cap that is stamped as square on the can. The opposite prong as the triangle and the semi circle is obvi
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  #66  
Old 06-03-2018, 10:49 PM
EdKozk2 EdKozk2 is offline
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Under the red wire is a triangle. Blue is connected to the half moon, as noted, and pin with no obstruction is the square. Outside perimeter tabs are ground.
Ed
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  #67  
Old 06-04-2018, 10:30 PM
Wind157 Wind157 is offline
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When putting a cap in parallel to increase its value, is that just voltage or capacitance too?
Have a paper cap that is .047 with 200 vdc. Can't find a cap that low with a minimum of that voltage. Found one that .05 but not sure if two would cause a problem
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  #68  
Old 06-04-2018, 10:44 PM
Wind157 Wind157 is offline
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Also, wtf is this? Pulled up a few times looking for replacement for paper caps. Do I just solder wires to the silver edges?
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  #69  
Old 06-04-2018, 11:19 PM
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Quote:
Originally Posted by Wind157 View Post
When putting a cap in parallel to increase its value, is that just voltage or capacitance too?
Have a paper cap that is .047 with 200 vdc. Can't find a cap that low with a minimum of that voltage. Found one that .05 but not sure if two would cause a problem
When you put capacitors in parallel, the total capacitance is the sum of the two capacitances. I think you understand that?

The voltage rating of the caps is not changed by putting them in parallel. So, for example, if you are replacing .047uf 200v with two parallel caps (say, two .022 uf) they must both be rated 200 v or more. If they are rated a higher voltage than 200, it doesn't hurt.
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  #70  
Old 06-04-2018, 11:37 PM
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Quote:
Originally Posted by Wind157 View Post
When putting a cap in parallel to increase its value, is that just voltage or capacitance too?
Have a paper cap that is .047 with 200 vdc. Can't find a cap that low with a minimum of that voltage. Found one that .05 but not sure if two would cause a problem
Capacitance is the ONLY value that adds when capacitors are connected in parallel. The voltage of a parallel capacitor combination is that of the lowest sticker voltage rating of any single cap in the parallel group.

Big space to separate topics:






If you want to combine caps in a way that increases the effective voltage rating then you have to connect capacitors in series...However that only works for a group of caps that all have the same capacitance rating (if not then the voltage will divide unevenly in ways that are a pain to predict). Also if you put capacitors in series the capacitance drops. which can be calculated for any number of individual parts wired in parallel by the formula: Ct=1/[ (1/C1) + (1/C2) + (1/C3) + ...+(1/Cn) ] where Ct is the capacitance of the parallel combo and C1 thru Cn are the individual parts that make up the combo. The ... and Cn mean you can calculate your result for a near infinite number of different caps of different capacitances.


Do NOT buy surface mount capacitors for replacing paper capacitors. Buy ones like these (which I use). https://www.mouser.com/ProductDetail...n1p2vhg7KKs%3d



good luck.
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  #71  
Old 06-05-2018, 10:08 PM
Wind157 Wind157 is offline
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Roger that. I just can't find one with such a low capacitance. Are these bumblebees often hard to find a replacement? Closest I found was what ever this is
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  #72  
Old 06-05-2018, 10:10 PM
Wind157 Wind157 is offline
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Oh so that a surface mount cap, yeah wasn't going to buy that amyway
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  #73  
Old 06-05-2018, 11:45 PM
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Yeah, the one in your post #71 is a surface mount part. What is the capacitance and voltage of the original you are looking to replace, but having a hard time finding?
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  #74  
Old 06-10-2018, 11:30 PM
Wind157 Wind157 is offline
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I'll get to those caps later. I'm taking care of the lytic caps first. Two replaced but on the third, which does have some damage, the image gets worse with the new cap. Reclip the old and it's fine again. The values match so I am not sure the problem.
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  #75  
Old 06-11-2018, 12:25 AM
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Can you show the other end of the cap. I suspect VNP means volts non-polarized...Meaning you can't replace it with a polarized lytic (though you may be able to replace it with two wired in series in a special way).

Another possibility is that the original is leaky and that leakage is compensating for another problem elsewhere...
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