Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Colas LeGrippa on September 19, 2012, 07:01:09 pm
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Hi buddies ,
VVr installed in a new build. When taking the reading onto the standby switch, when off, VVR works perfectly. When standby is thrown to ON, VVR reading decreases to 15 V or so. Whitout VVr, amp works just fine but I'd prefer to lower the voltage to a certain degree. Any idea with this issue ?
Colas
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1'st off, where you been buddy? I've been worried about you. :icon_biggrin:
2'nd not enough information. Output stage, PP or SE, cathode or grid bias, B+ voltage at plate and screen. What is the set up you have for the VVR, what's the mosfet, how's it wired, is it heat sinked....?
Please post a schemo with all the #'s and how you have it wired up, including what is VVR'ed.
Brad :think1:
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Hi Colas
are you sure the VVR is by itself in good shape ?
K
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Thanx for worrying, guys. You are so great and experienced ( not the Hendrix way, I hope ) that because of all you all of my builds are trouble free! :worthy1:
The VVR was working in that particular amp until i swap the OT for a stronger one. Then the VVR busted. When I put back the original OT, VVR was still out of order.
I have followed installation instructions with diodes at the B+ in and out and as I said, everythiong was working fine. I think the mosfet can't supply enough current ( rated at 10A, but my amp doesn't draw even 1 A ). I will swap the mosfet and get back to you. For now I am running this SE with too high a voltage ( 420V )
Regards
Colas
P.S. did you kiss your wife this morning ? don't get no bad habbit: she'll get frustrated and start throwing peanut butter jars to you. By chance , they're made of plastic now.
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Hi, I just checked the SS post about the NE2973 mosfet transistor. No reliable device, it seems !
Colas Coca.