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  #16  
Old 11-20-2017, 02:00 PM
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bandersen bandersen is offline
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Yes, I'm surprised you ask. I know you've replaced them in Motorrola VT-71s.
Selenium rectifiers gradually increase in resistance over time even when not used. Eventually, they fail in a big cloud of very foul smelling smoke. Took days to get the smell out of my place last time it happened
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  #17  
Old 11-20-2017, 03:06 PM
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Quote:
Originally Posted by bandersen View Post
Yes, I'm surprised you ask. I know you've replaced them in Motorrola VT-71s.
Selenium rectifiers gradually increase in resistance over time even when not used. Eventually, they fail in a big cloud of very foul smelling smoke. Took days to get the smell out of my place last time it happened
What I mean is it important to use resistors with the diodes.
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  #18  
Old 11-20-2017, 05:49 PM
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The 12dq6 and 12dq6b are these for the most part the same, could it be used in the admiral which had the one without the b .
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  #19  
Old 11-21-2017, 09:17 AM
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Quote:
Originally Posted by timmy View Post
What I mean is it important to use resistors with the diodes.
I don't know for sure. Definitely if you don't use them B+ will be higher than specified - especially if your AC outlets are more than the 117 VAC it was designed for. I'm use something like 47 to 100 ohms 5W and see how B+ measures once the set is up and running.

Quote:
Originally Posted by timmy View Post
The 12dq6 and 12dq6b are these for the most part the same, could it be used in the admiral which had the one without the b .
Yes, generally speaking tubes with A, B, C etc suffixes have superior specs to the earlier version and can sub for them.
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  #20  
Old 11-21-2017, 09:39 AM
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Quote:
Originally Posted by bandersen View Post
I don't know for sure. Definitely if you don't use them B+ will be higher than specified - especially if your AC outlets are more than the 117 VAC it was designed for. I'm use something like 47 to 100 ohms 5W and see how B+ measures once the set is up and running.



Yes, generally speaking tubes with A, B, C etc suffixes have superior specs to the earlier version and can sub for them.
Do you know what the b+ voltage is on that admiral ?
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  #21  
Old 11-21-2017, 10:28 AM
tom.j.fla tom.j.fla is offline
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Main B+ is 255 volts going by the SAMS. Go to the ETF site and download the folder for the tv. Tom.J
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  #22  
Old 11-21-2017, 11:09 AM
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I read bandersens thread on the same tv I have, and he changed the dual diode because of lousy horiz lock and I'm wondering if I could use a dual diode that are normally in the color sets the small black block with the 3 legs. If I should need to change it.
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