Tubes Asylum

Posted by gojamo on November 03, 2002 at 15:50:12

I made an otl amplifier using 4 6hj5 beam power tetrodes , triode connected, much like Andrea Ciuffoli's "totem pole" designs . For my next project, I thought about using 26lw6 beam power tetrodes connected as beam power tetrodes. I would use a bi-polar power supply +150v, -150v. I believe the easiest way to do this is to connect the screen of the lower tube on the totem pole to ground through a low value resistor (500 ohms?), and connect the screen of the upper tube to the plate with similar low value resistor, and to the cathode with a capacitor of a few hundred uf. will anyone with knowledge of tube circuit design comment on the feasability of this? I havn't seen any designs of the totem pole conformation wired in pentode or tetrode mode. I thought that there may be a power output increase similar to conventional push pull transformer circuits, but wonder about how the inherent imbalance of the upper and lower tubes may be detrimental. Thanks for your advice.

Andrew