Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Skip Hagey on January 07, 2016, 11:20:39 am

Title: very weak ground light on AC protection bulb
Post by: Skip Hagey on January 07, 2016, 11:20:39 am

I've been through the testing phase again on this 5y3 build and I've got a very weak glow on the AC protection bulb and a sight hum in the output. All I have is a multi-meter to test with.  No glow with the rectifier in and the output tubes out of the circuit, but a glow with either or both Power Tubes in the circuit.   What am I missing?

Title: Re: very weak ground light on AC protection bulb
Post by: sluckey on January 07, 2016, 12:40:15 pm

Talking about a current limiter light bulb? If so, that's normal.

Abnormal would be a bright bulb. A full bright bulb would indicate an amp that looks like a dead short.

Title: Re: very weak ground light on AC protection bulb
Post by: Skip Hagey on January 07, 2016, 01:14:07 pm

Thanks Steve, Happy New Year!