VH4 Biasing tutorial disappeared??!!!

[noiseinurhead]

Hi There!!
A few months back I saw a really cool biasing tutorial for VH4 that was posted By Mr Olaf Krampe I guess.
I was thinking that it was great because I wanted to try to rebias my amp(VH4S) by myself and I can't find it now that the time as come...
Why remove such great thing from the forum?Is it too dangerous to make the operation on a VH4?
:?

 

[duesentrieb]

Are you familiar with high voltages and biasing?

I just took it off here and the website since it can be dangerous, you know . . .

1) Take amp out of headshell
2) post onto two books and flip it
3) hook amp to load
4) hook DMM set to 200 mA DC with croco leads to OT, red to middle of secondaries, black to either side
5) switch amp on, volume =0
6) read DMM
7) adjust bias trimmer

Calculations (you are reading pairs !

EL34 = 25 Watt
6L6GC = 30 Watt

EL34:
25W * 600*2/480V = 62mA

6L6GC:
30W * 600*2/480V = 75mA

8) switch amp off and unhook crocos after you repeated the procedure for the other pair

Olaf

 

[duesentrieb]

btw: Diezel recommends to use an adaptor like

Bias Rite by www.tedweber.com

or

Bias MAster by www.tubeampdoctor.com

or Bias-Adapter by www.tubetown.de

 

[noiseinurhead]

Thanks a lot Olaf YOU'RE THE MAN!!!! :hump:
I will try it next week!!
If you have no news from me then I will be dead héhéhé
Just kidding, don't worry I'll take care I'm not used to do that kind of things but I will do it with a friend of mine who is...
Thanks again,
Cheers,
Christophe.

 

[duesentrieb]

The stereo version also reads pairs, but you have two OTs of course . . . and two bias trimmers . . .

 

[guitarobert]

>|<>QBB<

Are you familiar with high voltages and biasing?

I just took it off here and the website since it can be dangerous, you know . . .

I thought the biasing tutorials were extremely helpful, especially the graphs that were added to show the acceptable voltage range. Any chance you could post them with a disclaimer that says something like "doing this is dangerous and could kill you"? The information was very useful.