need advice on firing up new board & caps 1st tim

[Geezer]

  Hoffman Amplifiers
    > Tube Amp Building - Tweaks - Repairs
        > need advice on firing up new board & caps 1st time      
 
<< Prev Topic | Next Topic >>  
Author  Comment  
bzzzt
Junior tube assistant
Posts: 1
(4/24/04 4:00 pm)
 need advice on firing up new board & caps 1st time
--------------------------------------------------------------------------------
 I just finished wiring up a new Hoffman board & filter caps assembly on a '59 Bassman reissue. The filter cap kit instructions say I should current limit the AC & charge the new caps for 20 minutes, but I don't know if I can do this without the tubes in place.

In order to safely install the tubes, I need to turn on the amp first without tubes & check all my voltages & bias current. But I shouldn't turn it on without first charging the caps properly...

....chicken or the egg here.....

How should I proceed?

Thanks!
 
GroundhogKen
Forum Moderator
Posts: 2353
(4/24/04 5:41 pm)
 Re: need advice on firing up new board & caps 1st time
--------------------------------------------------------------------------------
 I usually just triple check my work and then go for it.

Keep a hand ready to flip off the power if necessary.

Just because caps are new doesn't mean that they've never been charged up before.

One cheap way to limit the power is to put a 60w light bulb in series with the power cord. There are links to this little trick around the web.


Ken
 
bzzzt
Junior tube assistant
Posts: 2
(4/24/04 7:11 pm)
 thanks
--------------------------------------------------------------------------------
 Thanks for the help Ken. I've got the series bulb trick ready to go. ....gonna go ahead fire it up now.
 
EL34  
I got your parts right here.
Posts: 2278
(4/26/04 10:26 am)

  Re: thanks
--------------------------------------------------------------------------------
 The board kit instructions on the library page give full details on firing up a new build.
 
 
 << Prev Topic | Next Topic >>

 

 Topic Commands
 Click to receive email notification of replies
  
jump to:  Tube Amp Building - Tweaks - Repairs (New)New Product Suggestions (New)Praises - Complaints - Suggestions (New)Buy - Sell- Trade (New)Archives (New)    
 

- Hoffman Amplifiers - Tube Amp Building - Tweaks - Repairs - Hoffman Amplifiers -



Powered By ezboard® Ver. 7.32
Copyright ©1999-2005 ezboard, Inc.