Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: MWagemaker on November 27, 2023, 08:56:37 am
-
Hi, I recently picket up the hobby of repairing my old amplifiers myself, then I got to the Vibr/trem channel of my vox ac30 nTB Bass issue.
I very much like to check if all values are still in range. I measured some phase shifts through the system, but it is hard to value this for me, because I have no reference.
Anyone measured actual the phase shift and amplitude at Point A and B, when refering to the point where the presumed phase shift is 90 degrees in the Wurlitzer mod 44, and is fed to the mod tube? at different frequencies?
Point is, I want to check the vibr.trem system in my vox ac30-6 nTB, without desoldering all components to check if they are in range.
Anyone an idee? or some actual data for comparison?
greetings
-
This was posted in the wrong board
moving..........................
-
Does the amp function to your satisfaction?
-
sorry, EL34, first post and I have to get used to the navigation. Do I have to do anything? you already moved the post.
The amp is Okay on bright and normal is best (both been modded by some former owner I can see from some treble caps and cathode bypass cap. But the vibr.trem channel is not okay, its dark, little muddy en general. I have checked all resistors as good as I could. Elcos are renewed. Couldent find any strange things.
Than I measured some fase shift through the system and I wondered how it is suposed to be, because only on some places, ie. frequency spectrum, I come to some degree of 90.