Selenium rectifiers have increased voltage drop over time. Replace the original with a silicon diode. Use 1N4004 or better. 1N4004 is rated 400 PIV and 1 amp. Selenium rectifiers are rated by plate size. Small ones, about an inch square, were rated 65 or 75 ma.
Add a series resistor, 47 ohms 1 watt, in series with the silicon diode.
B+ side of a silicon diode is banded (cathode). On a selenium rectifier it's marked +.
Norm
:I have low B+ and have essentially removed all loads. As I add the loads back in one at a time the B+ drops with each addition. I suspect the selenium rectifier is bad but I don't know how to test it. Anyone know how I can verify a bad one? Also, I am not sure how to replace if bad...I have several rectifiers in a parts box that look similar. Does the size matter? Also, do you connect the hot side of AC to the side marked "+" on the rectifier? Any help would be appreciated..