[Heathkit] Re: SB-620 Diodes

[Ken Kaplan]

Richard,

Good question as it got me curious enough to open up my SB-620. The parts you refer 
to are diodes D3 & D4. I've never seen a part like that before. The only seleniums I'm 
familiar with are the square plate type. I took a picture of mine. It can be seen at:

http://www.qsl.net/kb7rgg/heath/sb620pic1.jpg

btw - the 3 big capacitors in my set are rather wet with some oily substance. There is 
actually a wet "puddle" between C47 and C49. Does this mean its time to replace these 
caps? Any good source for such high voltage types? C48 & C49 are .1uf at 1200vdc and 
C47 is .15uf at 1600vdc.

I haven't had power on this scope for quite some time. I am in the planning stage of 
setting up a complete station (SB100/SB600/SB610/SB620/SB630). I just need to build 
a desk to hold everything. It's my motivation to upgrade my license.

73 Ken kb7rgg

> Hello to group.
> I am repairing an SB-620 and require the two selenium diodes   P/N 57-44
> Does anyone  have suitable cross reference replacement ? /  specs?
> My web search has come up zip.
> Richard / VA3NDO