Posted by hurdy_gurdyman [ 4.229.162.146 ] on September 04, 2005 at 22:52:04:

In Reply to: Re: Fisher 500C-how hot is too hot? posted by Damir on September 04, 2005 at 18:59:52:

Thanks for the help. I've never been any good at math formulas.

I changed the resistor on the bias bridge rectifier-to-ground from 15 ohms to 2 ohms and got the voltage to -24 VDC. This also, unfortunately, raised the fillament voltage on four 12AX7's higher than what is good for them, so I added a 16 ohm resistor in series whith them and have them right where they should be.

I'm a bit worried about reducing the bias resistor anymore. Not sure if the transformer tap and rectifiers are up to a lower resistance than this or not (not sure if it's up to the valule I have on it now.) Is -24 V close enough, or should I try an even lower resistor?

Dave

Replies:

• Re: Fisher 500C-how hot is too hot? - Damir 06:43:48 09/05/05 (2)
  • Re: Fisher 500C-how hot is too hot? - hurdy_gurdyman 10:45:56 09/05/05 (1)
    • Re: Fisher 500C-how hot is too hot? - Damir 12:32:51 09/05/05 (0)