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  #1  
Old 11-01-2019, 02:54 PM
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zeno zeno is offline
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Just check for AC ( to GND) on both sides of C1. If there check the
supplies # 1, 2, & 3 for DC.
Keep in mind most the time things in Sams flow left to right.
Try to find a mid point & test voltage. Go upstream or downstream
from there.

73 Zeno
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  #2  
Old 11-01-2019, 02:56 PM
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Dubis7 Dubis7 is offline
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Quote:
Originally Posted by zeno View Post
Just check for AC ( to GND) on both sides of C1.
Is C1 AC? I've been checking on the DC setting.
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Old 11-01-2019, 06:10 PM
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Dubis7 Dubis7 is offline
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Quote:
Originally Posted by Dubis7 View Post
Is C1 AC? I've been checking on the DC setting.
Yeah, I'm thinking C1 is DC because of where it is in relation to the diodes, but please correct me if that's wrong.
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Last edited by Dubis7; 11-01-2019 at 06:10 PM. Reason: Fixing "CD"
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Old 11-01-2019, 11:09 PM
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jr_tech jr_tech is offline
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Quote:
Originally Posted by Dubis7 View Post
Yeah, I'm thinking C1 is DC because of where it is in relation to the diodes, but please correct me if that's wrong.
There is ac on both sides of the cap, but the output is shifted up dc wise. See video of voltage doubler circuit.

https://m.youtube.com/watch?v=Iq-5PPpVHNw

jr
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  #5  
Old 11-02-2019, 03:57 PM
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Dubis7 Dubis7 is offline
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Okay, I found my problem!

R119 is several million ohms. It's supposed to be 3.6 ohms. I jumped it with some alligator clips (briefly) and the TV came back to life!

So I'm going to order another R119 and get back to work on this.

Thanks for your help so far, everyone. Next step is to make sure it powers up with all that fixed, and replace C3. Hopefully that will close this whole thing down.
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Old 11-02-2019, 04:05 PM
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Dubis7 Dubis7 is offline
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Hm, having some trouble with this one. Does anyone have a good source for 3.6 ohm resistors with 7 (or highter) watt ratings? Any thoughts on how flexible this part is going to be? Would a 3 ohm do it?

If I did them in series, I could get a 3 ohm and .5 ohm 10 watt resistor from JustRadios, but I'd prefer to use one part is possible.
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