Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Colas LeGrippa on March 17, 2019, 12:22:22 am

Title: Oscillation problem solved
Post by: Colas LeGrippa on March 17, 2019, 12:22:22 am
In a high gain amplifier just finished I was experiencing crackling noise followed by a huge howling kinda noise. Everytime I had to turn the amp off . I thought the prob was coming from the master volume circuit installed recently.
I passed the afternoon and part of the night on that prob. I put back pnce again the amp on my bench for the 2 hundreth time and taking the voltage readings I discoveted one of the EL34  was not drawing any current due to a.......defective 1 ohm resistor on the cathode.
When I looked under, the other one wad red plating obviously. Replaced the 1 w resistor by a 5 w. Test ok. No oscillation nice disto.
I am running to my bed.
Title: Re: Oscillation problem solved
Post by: Colas LeGrippa on March 17, 2019, 10:52:53 am
On the way to my bedroom after brushing my teeth ( f...the shower I gotta sleep) I was happy to have solved what I tought to be the biggest problem of my day. I was mistaking: she wasn't sleeping omg.


Pepsi Colas.