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Hoffman Amps Forum image Author Topic: 12V Heater Question  (Read 2099 times)

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Offline offabit2001

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12V Heater Question
« 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

Offline PRR

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Re: 12V Heater Question
« Reply #1 on: October 30, 2019, 10:15:31 pm »
"A" puts dead-zero across the heater. Nothing happens.

"B" is what you want.

Offline offabit2001

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Re: 12V Heater Question
« Reply #2 on: October 30, 2019, 10:25:59 pm »
Thanks for the info.

Offline glass54

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Re: 12V Heater Question
« Reply #3 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
« Last Edit: October 31, 2019, 05:31:57 pm by glass54 »
"To measure is to know"

Offline offabit2001

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Re: 12V Heater Question
« Reply #4 on: October 31, 2019, 12:05:27 pm »
Awesome, exactly what i was looking for. Thanks

Offline glass54

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Re: 12V Heater Question
« Reply #5 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
"To measure is to know"

 


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