>
> Anyone,
>
>
> Ok, Ok, I can't stand it. It may be a dumb
>question but just what is the 'G2DAF' design,
>and the principles behind it?
>
>Mark WB8JKR
>
Two of my pals built DAF's. They called 'em Class C linear amplifiers.
Instead of 60 percent efficiency, the efficiency was allegedly 75 to 80
percent. They used tetrodes. The grids were driven well into the grid
current region. The screen supply voltage varied with modulation. With
no modulation, the tubes were cut-off. With voice modulation, total IMD
was c. -22db. Both pals eventually realized that the DAF circuit was
DAFT and converted the amplifiers to grounded-grid operation, which
improved the IMD by over 10db.
- later, Mark
Rich. Measures. Web site: www.vcnet.com/measures
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