Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Oddvar on September 11, 2016, 03:43:49 pm

Title: AC30 layout and heaters on board
Post by: Oddvar on September 11, 2016, 03:43:49 pm
Hi again.

I am building a Vox AC Hoffman at the moment and I am a bit puzzled on how the heaterconnections are.  On the board there ar two squares indicating heaterconnections.  Is it going from the PT to the pilotlight to the two points on the turrretboard?

There is also a cut potentiometer with indications of a strip connected to it, is that special pot or just  regular grounding?
Title: Re: AC30 layout and heaters on board
Post by: sluckey on September 11, 2016, 04:08:07 pm
Quote
On the board there ar two squares indicating heaterconnections.
Connect the PT heater wires to the indicator lamp. Connect a 20AWG  twisted pair to the indicator lamp and also to the tube sockets. Connect another twisted pair (can be small wire like 22 AWG) to the indicator lamp and the board. There will be 3 wires on each of the lamp socket lugs.

Quote
There is also a cut potentiometer with indications of a strip connected to it, is that special pot or just  regular grounding?
It's not a special pot and it has nothing to do with grounding. There is a small terminal strip conveniently soldered to the back of the pot. This is used only to connect that cut cap to the orange wire. The terminal strip could even be screwed to the chassis. Or, you could put one more turret on the board and completely do away with the terminal strip.
Title: Re: AC30 layout and heaters on board
Post by: Oddvar on September 12, 2016, 04:36:43 am
Thanks.