Re: 7904 with vertical problem


Göran Krusell
 

Hi, quite possible that you have an oscillation here. If so something is broken. What you can do is to measure all DC voltages in this amplifier and compare with the schematic. If you find unexpected voltage levels it would be an indication of instability and oscillation. You can also poke around with a wet fingertip and check if the noise would disappear at some point.
Göran

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