...snip...
>I guess the question I have is why anyone would wish to give up a bullet
>proof workhorse amp such as the AL-1200 for something completely unknown
>with no track record such as the QRO?
Ummmm. A spirit of adventure? There's a Ben and Jerry's on the way to
UPS? The color of the AL-1200 cabinet clashes with the color of the
carpet? He followed the VHF parasitics debate?
>The power output differences are marginal,
--true
>... ...Besides those 4CX800 tubes are in AB1 and require constant ALC
attention.
>
I built and use an 8169 Class AB1 grid-driven amplifier. (to my great
regret and embarrassment, alas, this tetrode does NOT have handles) An
ALC circuit would be as useless as the teats on a boar hog because I made
the 8169's grid bias V adjustable. Long, long ago I set the bias V
adjusment so that my TS-440S could not produce grid current. I have not
re-adjusted the bias V in at least a year. As I recall, the bias V is
set to about neg. 240v. When I switch to a different anode supply V, I
set the ZSAC to 0.4A with the screen V adjust, as Eimac recommends.
Rich---
R. L. Measures, 805-386-3734, AG6K
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