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ZNFB UL Transformer Coupled Amp Questions

11/5/1999 6:24 AM
Morris	ZNFB UL Transformer Coupled Amp Questions Greetings all. I'm interested in building a ZNFB UL amp powered by a pair of cathode-biased 6V6's. I also want to use a transformer for phase inversion. I have a Hammond 1608 OT and a 1:3 interstage transformer I got from AES (10 MA, 10,000 to 90,000 primary to secondary impedance). What driver tube should I use? B+ for the PI transformer? Ground the center-tap on the PI transformer secondary? Plate and cathode resistor values on the driver tube? Can I connect the PI secondary wires directly to the 6V6 grids, or are series resistors necessary? Thanks in advance for all your advice.

11/5/1999 6:24 AM

Morris

ZNFB UL Transformer Coupled Amp Questions

Greetings all. I'm interested in building a ZNFB UL amp powered by a pair of cathode-biased 6V6's. I also want to use a transformer for phase inversion. I have a Hammond 1608 OT and a 1:3 interstage transformer I got from AES (10 MA, 10,000 to 90,000 primary to secondary impedance). What driver tube should I use? B+ for the PI transformer? Ground the center-tap on the PI transformer secondary? Plate and cathode resistor values on the driver tube? Can I connect the PI secondary wires directly to the 6V6 grids, or are series resistors necessary? Thanks in advance for all your advice.