Silver Lining

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Posted by Tnuctipun [ 64.12.116.14 ] on February 16, 2005 at 09:50:36:

Hey-Hey!!!,
One of the things I have run up against with low B+ Class A amps is a lack of headroom for a driver stage( and I've been watching *WAY* too much Stewart Little).

Two power TX's are a bit of a PitA. The Guinevere Iron, when built into a PP 6V6 amp would run the power stage B+ on the 325 taps. The drivers could be done on the 400v taps.

It would be dificult( close to impossible I think ) to do an E-Linear driver at different DC w/o a tertiary winding. A resistive hook-up from plate to grid *IS* possible. The two B+ supplies do require a bit more realestate and expense.

For something low mu like a pair of 45's the additional headroom would be a useful feature. A 10k a-a OPT would do PP 45 quite nicely and with reasonable PS headroom. 45's are a bit small in the power department. 3W is what I would expect. I'd suspect that we could get away with a bit more than 100 mA with an L-C PS, and taking the load for the rectifiers off the core. 2A3's would be cool and a reasonable maximum. 6 or 7 watts with a 6k a-a OPT. They'd be a good 6 or 7W...
regards,
Douglas



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