Ah, just like an o/p TX then!Nick wrote:...think of it as a impedance converter instead.
Re 'Transformers bad', I wonder what the original Circlotron designers were trying to achieve ("best amplifier in the world?" Dave!!) in the 1st place bearing in mind that most of the early designs used o/p TX's like you said. The Wiki page just makes mention of the fella's going after the patent and how later by //-ing o/p tubes the Circlotron evolved into OTL's.
6AS7 seems a popular choice and I read that a pair in // can easily drive high Z headphones in OTL amps...
Then I remembered thats sorta what I've got I've got an early 'Little Dot' headphone amp, it's a cheapy Chinese OTL headphone amp that runs Chinese 4P1S which are close I believe to Russian 4p1L directly heated pentodes in OTL IIRC.
Funny that.
Yeah Mike, if thats from Rainer's book of Elektor ccts, yeah I saw that, It my eye too.MikeH wrote: Somewhere got an Elektor circuit, it's got a complicated driver cos it has to do the whole primary Voltage for the o/p transformer. It's got EL34's but they just work as big CF's, all the Voltage swing has got to come from the driver.
DTB