At 08.51 1997-12-22 -0800, you wrote:
>>At 03.38 1997-12-22 -0800, you wrote:
>>>>>Grandfather Measures used to say: "There is no such thing as a free
>>>>>lunch."
>>>>
>>>>Rich,
>>>>
>>>>Are you suggesting that things have changed, and that there is such a
>>>>thing as a free lunch?
>>
>>AG6K:
>>no. The g2daf promises a free lunch. There is no free lunch and no
>>Class C linear.
>>
>>Wrong. G2DAF never promised a free lunch (at least not for me....)
>
>It promised higher efficiency in a linear amplifier. It delivered higher
>effiency. The trade-ff was linearity.
>
>>Right. I agree that there is no linear class C amp, but with floating
>>class of operation there are several examples...
>
>The only class of grid driven linear service is AB1 -- {although the
>4cx1500B and 4cx600J can tolerate up 0.5mA of grid current, yet remain
>linear}.
>... ... ...
>>Not that you have asked for it, Rich, but I guess I cant resist to send
>>you the plotted linearity-graph (using HP spec.) as a special xmas gift
>>for You! ;)
>>
>Thanks, Lars. I read the graph over. However, the IMD test that really
>counts is dynamic -- i.e., how many db down is the SSB voice splatter in
>the two windows adjacent to the fundamental signal. This is what your
>fellow amateur radio operators are going to hear.
>- It seems to me that grid bias supplies and screen supplies are pretty
>easy to build. The AB1 bias supply produces zero current, so regulation
>is not needed. The 723 IC and power FETs make screen regulation a piece
>of cake. 60% vs. 75% efficiency hardly makes a difference on the Rx
>S-meter.
>Rich...
>
No offense Rich, but it seems to me that "you`ve hit the wall..."
/Lars
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