Posted by Damir [ 213.202.69.77 ] on May 02, 2005 at 07:32:06:

In Reply to: DRD 300b set amp posted by Forty2wo on May 01, 2005 at 21:38:30:

Not tried it in the real world, but it`s the pleasure to SPICE it and look at the clever & tricky way this amp is made. Anode current for the 300B is ~70mA, and Ia for the paralelled input tubes ~14mA. Direct coupling, bias voltage for the 300B "made" partly from Rk, partly from DC voltage drop across Rw (about 1k4) of the choke... Tricky, but simple enough!
The only concern is high B+=700V and even higher HV PT winding- 1110 Vct...
Many people already built this or similar "Monkey/DRD" amp, I found lot of info in the DIY archives... Good luck, and post about the building it, photos, etc

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