• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Universal tube preamp PCB, ECC99/6N6P/ECC88/ECC85/6922/6DJ8 etc. MU follower or SRPP

Joined 2017
Paid Member
Good evening,
I found the problem!
One ground trace is missing on the pcb, so pin 37 40 4143 46 49 52 were not grounded... Incredible nobody got the problem before 🤔
Anyway finally working 👍👍👍👍👍
Let's listen now 😊

Hope it helps


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