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  #46  
Old 05-24-2018, 09:49 PM
WISCOJIM WISCOJIM is offline
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Looks original, probably just a production change. Doesn't mean Sams is wrong, often manufacturers make a lot of changes along the line.
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  #47  
Old 05-24-2018, 09:51 PM
Wind157 Wind157 is offline
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This also makes me suspect it's had work done too. The cap in the picture shows a paper cap but the one in place clearly isn't. It isn't new either so either it's been replaced some time ago or a different one was used in the first place.
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  #48  
Old 05-25-2018, 11:35 AM
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zeno zeno is offline
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Not sure where things are at but I think you are referring to C56.
Sams shows a white paper cap. The TV has a bumblebee.
Probably the factory changed suppliers.

As far as the original vert problem goes replace the burned resistor.
See if it still works. Its possable whatever went wrong it shocked a cap into
working again.

73 Zeno
LFOD !
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  #49  
Old 05-25-2018, 02:39 PM
Wind157 Wind157 is offline
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I did connect the cap to the wrong spot and now that it's in the right place and old cap removed it works great. Still will need to replace the resistor and other caps but working for the moment.
Thanks for everyone's help.
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  #50  
Old 05-25-2018, 04:45 PM
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BTW when we say paper caps we are referring to the dielectric inside the cap and not it's outer casing. The white tubular ceramic caps in some of the pictures and the aforementioned bumblebee caps are paper dielectric caps, and should be changed.
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  #51  
Old 05-27-2018, 11:17 PM
Wind157 Wind157 is offline
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Last question and it probably sounds dumb but it's my luck is pick wrong. When ordering a new cap I want to look for AC caps correct?
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  #52  
Old 05-28-2018, 04:24 PM
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delete duplicate.
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  #53  
Old 05-28-2018, 04:25 PM
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AC caps are almost never seen in TVs. Lytics and paper caps both new and original are and were rated for DC voltage.

Many new film/paper types are given both AC and DC voltage ratings... ignore the AC rating and choose new ones based on their DC voltage rating.

In most applications a cap would have something like 400VDC across it and maybe 5VAC of signal.... if it can handle the 400 DC then it can handle the 5 ac easily.
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  #54  
Old 05-28-2018, 08:51 PM
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Glad I asked then.

How far below capacitance can I go? I need to replace one that is 150 but closest is 120 and that's with being a good deal higher in voltage
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  #55  
Old 05-28-2018, 10:17 PM
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Lytics typically were +100%/-50% tolerance on the capacitance so 75uF would be the lowest you can go on a 150uF. Papers typically have a 10% tolerance. Most sets don't mind some variance in the capacitance of lytics, but papers can be more critical especially in any stage of a TV other than audio or power. In some cases (usually paper caps) if I don't feel I can get a precise enough value for the circuit I'll put two capacitors in parallel to get the value I need (capacitances in parallel add).

The closer the better but 120 should be plenty close to 150...If you get excessive hum on the line it filters after the recap you can always tack a 33 or more on in parallel with the 120 after the fact.
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  #56  
Old 05-29-2018, 10:47 AM
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Thanks. I ended up finding one at 140 but voltage was 400 instead of 300. Fitting it will be fun.
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  #57  
Old 05-29-2018, 01:04 PM
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...

Last edited by andy; 11-18-2021 at 04:57 PM.
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  #58  
Old 06-01-2018, 08:38 PM
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Replacing the caps in a can, the negative of the new cap connects to ground?
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  #59  
Old 06-01-2018, 09:17 PM
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Quote:
Originally Posted by Wind157 View Post
Replacing the caps in a can, the negative of the new cap connects to ground?
The negative of the new cap(s) connects to whatever the metal housing of the original can connected to...

Many cans were soldered directly to chassis ground, but others rather than connecting the can to ground, connected it to a floating negative rail.
The original can will have 3-4 outer twist tabs coming from it's bottom...If the twist tabs contact and are soldered to the chassis metal then the can is grounded to chassis....But if the twist tabs are twisted onto a phenolic insulating wafer (the wafer is riveted to the chassis in 2 places) then the can connects to a floating negative rail (and your replacement(s) should then connect to the floating negative rail instead of the chassis). Another giveaway that a can is on a floating negative is when the metal can above chassis is wrapped in a cardboard or plastic insulator.

If that is confusing then ask me for some pictures tomorrow...Visual aid makes my point come across with at least a thousand fewer words.
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  #60  
Old 06-01-2018, 09:42 PM
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No that makes sense. There are a few of the floating negatives on the chassis. This can however doesn't connect to any just the chassis and the wires leading to their various points.
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