Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: offabit2001 on October 30, 2019, 09:35:20 pm

Title: 12V Heater Question
Post by: offabit2001 on October 30, 2019, 09:35:20 pm

Could you guys tell me which way to wire the 12v heaters from the 12v regulator. Do I add an extra wire coming off the positive (+) side of the regulator and hook up one of the positive wire to lug 5 and another + (positive) wire to lug 4 on the tube or does one positive wire coming from the regulator goes to lug 5 and the ground wire coming from the regulator goes to lug 4 on the tube? See picture attached. I circled in red the 12v heater hook-up like A or like B?  Another question is, does the negative lug of the regulator get grounded to the metal case or somewhere else? Thanks

Title: Re: 12V Heater Question
Post by: PRR on October 30, 2019, 10:15:31 pm

"A" puts dead-zero across the heater. Nothing happens.

"B" is what you want.

Title: Re: 12V Heater Question
Post by: offabit2001 on October 30, 2019, 10:25:59 pm

Thanks for the info.

Title: Re: 12V Heater Question
Post by: glass54 on October 31, 2019, 12:19:50 am

Hi Offabit
I would run the DC Closer to 12.6V DC (Not ultra critical but nice).
Please see attached drawing that I used for a Double Bass Tube Preamp some years ago and still going strong.
You can use the 4700uF and LED as per your drawing.
Kind Regards
Mirek

Title: Re: 12V Heater Question
Post by: offabit2001 on October 31, 2019, 12:05:27 pm

Awesome, exactly what i was looking for. Thanks

Title: Re: 12V Heater Question
Post by: glass54 on October 31, 2019, 08:23:16 pm

....and don't forget your 33k (or something suitable) grid stopper at Pin2 on input tube V1  :laugh:
Kind Regards,
Mirek