Preferred wiring for 80/40/30/20 CE/Dynakits Caps

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Preferred wiring for 80/40/30/20 CE/Dynakits Caps

Postby mugsy » Thu Jul 24, 2008 3:29 pm

Hi folks.

Thought this thread might help some newbies (and 'in-the-middle' bees like me!) or those upgrading the caps in their ST70s.

The accepted wiring scheme for the newer quad caps seems to be:

40uF --> choke --> 80uF --> 6K8 --> 30uF --> 22K --> 20uF

What is the consensus on wiring to points 19 and 20 on the original driver boards? Is it best for the 30uF tab to be soldered to pin 20, and the 20uF section to pin 19, or doesn't it matter?

Secondly, if using a modern Triode 'Dyna-Clone' power transformer, do those 6K8 and 22K resistors on the Quad cap need their values changed?

Thanks!

- John
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Postby mesherm » Thu Jul 24, 2008 5:17 pm

What is the consensus on wiring to points 19 and 20 on the original driver boards? Is it best for the 30uF tab to be soldered to pin 20, and the 20uF section to pin 19, or doesn't it matter?


The sections are so close in value that it probably doesn't matter. I personally prefer the 30uf on the phase splitter but its probably a push either way.

The 6.6k and the 22K are values chosen to give a specific voltage drop based on the driver section current draw and provide de-coupling for the driver stages. They shouldn't change just because a Dynaclone PT is being used.
Mike's N-1 Rule: When looking for N number of components to finish a job, you have a 95% chance of only finding N-1 of them.
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Postby mugsy » Fri Jul 25, 2008 9:03 am

Thanks Mesherm Yellow_Light_Colorz_PDT_12
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