VH4 bias pot issue

  • Thread starter Thread starter jhaudio1
  • Start date Start date
jhaudio1

jhaudio1

New member
Hi guys,
This is my first post. My VH4 shut off during sound check at a gig last weekend. The main fuse popped so I followed the instructions in the sticky and put in some new tubes after replacing the fuse and successfully powering up with no tubes as suggested. I went on to bias the amp, noticed that I was getting no reading and started blue planing my tubes. The bias pot on my amp is hanging off the circuit board by about an inch, held in place only by some solder covered wires which look patched together. One of the wires was broken where it meets the circuitboard which explains my symptoms (hopefully the fuse is the only damage that happened). It just seems strange to me that the bias pot is not fixed to the board like the pics of other diezel models and I can't find a clear pic of what the bias pot should look like on a VH4. The thing is... I am the first owner of this amp so I know it's never been tampered with. Is it typical for the bias pot to be hanging like this? With the exceptional build quality of every other facet this amp, it just seems completely out of place. Any help or pics would be greatly appreciated.

Thanks!
J
 
How old is the amp? Older VH4's didn't have a bias pot, perhaps yours is a mod?
 
Welcome to the board, J .

What´s the serial number of the VH4 and where was
it serviced last time ?

Thanks,

Peter
 
Thanks for the quick response guys

Serial# 070830

amd never modded

The only person I'd let touch my amp was a friend of mine who showed me how to change tubes and bias the amp. He had pointed out before that you have to be really careful working around this bias pot because of how it's mounted. I just had it repaied today by a reputable amp tech. He said that it was prpbably mounted this way because of the placement of the leads on the pot making it impossible to mount on the board. He made the connection stronger and I'm getting my amp back tonight.

But is there a fix for this problem going forward?
I don't like being seperated from my diezel...
 
You must log in or register to reply here.
Back
Top