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Diodes [message #28368] Thu, 28 October 2021 15:43 Go to next message
DocWaxham is currently offline  DocWaxham
Messages: 46
Registered: October 2018
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Can you use a 1n5822 in place of 1n5801? Thanks

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Re: Diodes [message #28369 is a reply to message #28368] Thu, 28 October 2021 17:16 Go to previous messageGo to next message
stevem is currently offline  stevem
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Registered: June 2004
Location: NY
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What Kustom amp uses a 1n5801?

In general, yes you can replace a lower number diode with a higher number one.

[Updated on: Thu, 28 October 2021 17:20]

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Re: Diodes [message #28370 is a reply to message #28368] Thu, 28 October 2021 18:32 Go to previous messageGo to next message
DocWaxham is currently offline  DocWaxham
Messages: 46
Registered: October 2018
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K200 correct number is nte5801.

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Re: Diodes [message #28371 is a reply to message #28368] Thu, 28 October 2021 21:02 Go to previous messageGo to next message
stevem is currently offline  stevem
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Registered: June 2004
Location: NY
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Where is this used in the amp, in the bias circuit of the output

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Re: Diodes [message #28372 is a reply to message #28368] Fri, 29 October 2021 10:15 Go to previous messageGo to next message
DocWaxham is currently offline  DocWaxham
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Yes it is. It is the one that has a heat sink with the output transistors. This is K200 amp also.

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Re: Diodes [message #28373 is a reply to message #28368] Fri, 29 October 2021 13:19 Go to previous messageGo to next message
chicagobill
Messages: 2010
Registered: April 2003
Senior Member
Almost any silicon diode can be used to replace the 1N3754 bias diode in there, but getting it to sense the heating of the output transistors is the real problem.

The diode is mounted to the heatsink so that when the output transistors get hot it will lower the bias current to the transistors. I've tried epoxying a small signal diode into a piece of 1/4" aluminum tubing as a replacement. I've also mounted a small two lug terminal strip to the heatsink and mounted a glass bodied diode so that it sat on the flat surface of the heatsink.

Anything that you can think of will probably work as long as you watch the polarity.

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Re: Diodes [message #28374 is a reply to message #28368] Fri, 29 October 2021 19:16 Go to previous messageGo to next message
stevem is currently offline  stevem
Messages: 4778
Registered: June 2004
Location: NY
Senior Member
Electronic parts outlet has the original 1n3754 for e7.50 .
Not bad for NOS from across the pond!

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Re: Diodes [message #28375 is a reply to message #28368] Sat, 30 October 2021 11:34 Go to previous message
DocWaxham is currently offline  DocWaxham
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Registered: October 2018
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I actually found some at American Microsemiconductor. Thanks to all.

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