Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: PharmRock on December 29, 2021, 11:59:07 am
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Hope everyone is having a Happy Holidays. I'm using my time off to finally tackle this JTM45 build that's been a pile of parts on my bench for the good part of 3-4 months.
I understand that the bias supply tap comes off one of the HV secondary wires at the rectifier tube socket. However, I am also running elevated heaters, which the circuit is adjacent to the bias supply (see attached image). Should I tap the other HV secondary wire to supply the elevated heaters, or can I use the same tap that I am using for the bias supply? That is, just tie the two circled turrets together and connect to single HV secondary?
Hope this makes sense. Thanks!
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There’s no benefit that I can see in heater elevation having a dedicated rectifier.
What’s the rationale for doing it like that?
See how Friedman does it with the Dirty Shirley https://ampgarage.com/forum/viewtopic.php?p=432913#p432913
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There’s no benefit that I can see in heater elevation having a dedicated rectifier.
What’s the rationale for doing it like that?
See how Friedman does it with the Dirty Shirley https://ampgarage.com/forum/viewtopic.php?p=432913#p432913
I am implementing the same design that I successfully used in a 50W SS-rectified Plexi build I did last spring: https://el34world.com/Forum/index.php?topic=27216.msg298901#msg298901 (https://el34world.com/Forum/index.php?topic=27216.msg298901#msg298901)
IIRC, because I am using a standby switch, tapping the HV secondary directly and then rectifying it with the diode on the board will allow me to have elevated heaters any time the amp is on, whether in standby or not.
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Ok, there may be a benefit (possibly minuscule) in keeping the loading on each half of the HT winding even :dontknow:
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Thanks...it won't be much more effort to run separate wires, even if the payoff is small. I'll tap from each half of the winding.