Parts list for Quad ESL 63 EHT board

Hi, I have an issue with my ESL 63. One of the EHT modules was only 1,2Kv dc out (measured without being linked to the panels) both trafos are delivering 630 Vac so I decided to repopulate that module with new components. Vishay diodes GP 02-40, SR Passives 10n/3Kv capacitors, new Vishay resistors. After that, the output was only 3,6 Kv dc. I've switched the modules with the good one and the ht was 4,8 Kv dc I've switched the neon lamp module and was the same. There is anybody to help me with a clue?
 
The fact that the caps are physically disconnected from the panels when the neon isn't lit is a pretty compelling argument for not being too concerned about the HV caps. Films won't hurt anything, but don't expect any sonic improvements. The trick is to find films that would fit on the board. You can lay out a new board with films and then everything is good.

Here's a new layout or the HV boards:

OSH Park ~



Sheldon
quadesl.com
@stokessd do you have any more information on these replacement PCBs / parts lists (any additional ones for the clamp board)? I have at least one EHT that needs to be rebuilt and a fresh pcb without the wax sounds like a good idea.

Thanks!
Greg
 
Here's the schematic and BOM for the HV board. With the supply chain issues, you will probably have to substitute some parts. The diodes are hard to get, you may need to use a different brand etc.

Also I haven't built up a set of these. They are simple and should work well, but Caveat emptor.

Sheldon


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