[Boatanchors] Heathkit SB-610 monitor scope

[Dick KF4NS]

Decided to dig into it again since I had not done much with it since I got it 2002 and replaced all the
power supply caps. Recent testing showed poor focus and low vertical gain.

I found the two B+ diodes shorted. Wow, never saw any selenium rectifiers that looked like those two. The
focus problem should be fixed after replacing the rectifiers and a few resistors. About those diodes, I
will likely use a couple 1N5408s but the usual thing would be to series a resistor with each anode lead
which is usually a good idea in power supplies with original seleniums. In this case though I wanted to
get you input because I noticed that the capacitors are not electrolytic and there shouldn't be the usual
increase in voltage. What do you think? One chap has a solution online whereby he used 4 1N4007s in
series for each replaced diode which I guess he thinks will make up for not using series resistors.

I also observed that the blue and yellow xfmr leads are reversed but don't believe that should be a
problem since we are looking at AC here and don't think secondary polarity should be of concern here.

I have a couple options here will take care of the vertical gain situation. Got that covered.

73, Dick KF4NS
St Petersburg, FL 33714 USA
Keep The Glow!