19-07-2020, 08:37 PM
(This post was last modified: 19-07-2020, 08:40 PM by Murphyv310.)
Hi.
I need to know the settings on the scope but the ripple "may" be wrong on the first image.
Did you increase the sensitivity for the second trace or was the settings the same?
Looking at the first image it is possible that only one side of the rectifier is conducting. Have you subbed the EZ81? On a cold check (no power) what is the resistance between pins 1 &7.
Being fair I have my doubts that the HT supply is the issue as the seconf image is fine there should be very little ripple on that section of the smoothing.
Next is to fit V3 and tell me if the hum returns.
I need to know the settings on the scope but the ripple "may" be wrong on the first image.
Did you increase the sensitivity for the second trace or was the settings the same?
Looking at the first image it is possible that only one side of the rectifier is conducting. Have you subbed the EZ81? On a cold check (no power) what is the resistance between pins 1 &7.
Being fair I have my doubts that the HT supply is the issue as the seconf image is fine there should be very little ripple on that section of the smoothing.
Next is to fit V3 and tell me if the hum returns.
