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Old December 15th 05, 07:20 PM posted to rec.radio.amateur.homebrew
Bill Turner
 
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Default To build or not to build

On Thu, 15 Dec 2005 04:42:33 +0000, Highland Ham
wrote:

That's a 20dB amplification ...a bit much for a single stage amp.


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That's true in grounded grid mode, but quite doable for grid driven.
According to the Amperex data sheet, a pair of 3-1000Zs in class B
grid driven mode will give 3560 watts out for 28 watts of drive. For a
single tube, that scales down to 127 watts out per watt in. 10 watts
in will give 1270 watts out, a power gain of 21 dB.

That's the only tube I've looked at so there may be others that will
give a full 1500 out for 10 in. On the other hand, 1270 is close
enough to 1500 that you'll probably never notice the difference.

You will have to neutralize it of course, lest you end up with a high
power VFO. :-)

73, Bill W6WRT