Bottlehead Kits > Mainline
It had to happen eventually... capacitor upgrade question for the Mainline
Loquah:
I'm just about to embark on some hot-rodding of my S.E.X. and it got me to thinking I should consider the Mainline next. Looking at it though, there aren't a lot of caps to play with as far as I can tell so I wanted to check if anyone can suggest any specific caps worth changing?
My first thought was the Dayton 10uF caps on the output tubes. Are these operating as output caps?
The only other caps I saw were the tiny yellow ones that bridge a couple of the pins on each output cap (I can't easily see them enough to provide a better description at the moment). Would these benefit from replacement with some nice Russian teflons?
Paul Birkeland:
The 10uF caps are the coupling caps. They can be 10-20uF, and probably should carry at least a 200V rating. (160V might work, but would really be pushing it)
The tiny yellow caps on the sockets are out of the signal path and implemented for silent operation. There's a good chance that if you swapped them for something else, that alternate cap would not perform as well, and you would likely end up with a dysfunctional Mainline.
The 0.1uF 400V capacitors on the center PC board can be swapped out as well. They won't have nearly the influence that the 10uF caps have, and the available space on the PC board is somewhat limited. You can help yourself out by using a 250V capacitor here, which will see more than 250V at start-up, but will operate at 225V otherwise, which I would consider acceptable.
-PB
xcortes:
Paul, i don't know the exact Mainline circuit but I know it's a spud so maybe instead of coupling you're referring to parafeed caps?
Doc B.:
Yeah, he means the parafeed coupling caps, that is, the caps that couple the plates to the output transformers.
xcortes:
Cm'on, you're usually not that diplomatic!
Navigation
[0] Message Index
[#] Next page
Go to full version