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Lifting heaters above cathode.

PostPosted: Thu Mar 17, 2016 12:16 am
by gavinhaley
I know that someone has done this my question is where on the PCB to put the voltage divider to get the 50vdc or so that I need. I thought about taking the voltage right after the choke might be a good place but I'm open to suggestions. I have some really nice Hashimoto output transformers on the way and a whole slew of nice parts for a really nice Clementine.

Gavin

Re: Lifting heaters above cathode.

PostPosted: Thu Mar 17, 2016 2:24 pm
by Geek
It's real simple. You need two resistors and a capacitor (to bleed noise).

First, you have to find out where your cathode is at for bias. Then calculate about +30-40V above that.

Re: Lifting heaters above cathode.

PostPosted: Fri Mar 18, 2016 12:37 am
by gavinhaley
Geek wrote:It's real simple. You need two resistors and a capacitor (to bleed noise).

First, you have to find out where your cathode is at for bias. Then calculate about +30-40V above that.


You don't understand. I know how to do it but I was looking for a convenient place on the board to do it. It looks to me like I could solder the voltage divider all together and place it between one side of J7 and the other to the GRD eyelet and then solder the center tap lead of the heater winding to the voltage divider. I would need 1/8th the voltage of the 396 VDC to lift the heaters high enough to clear the cathode voltage of the 6L6s.