>> From: Rich Measures <measures@vc.net>
To: <amps@contesting.com>
>> Date: Tue, 22 Jul 97 03:19:59 +0000
>
>> > it ain't grid current that's the defining
>> >characteristic! it's the linearity! the "transfer characteristic"
>> >should be a straight line. if it bends, then it ain't linear.
>>
>> Agreed. With grid current, the line bends.
>
>No, that is not true. ...
...snip...
> I've seen many PA's get cleaner as grid current appears.
You also said you had seen dozens of Class AB1 grid-driven triode RF
linear amplifiers, and you still have not named even one of the tubes
that was allegedly used, Mr. Rauch.
>An 8877, drawing grid current, can easily be in the mid forty to
>fifty dB down IMD range, ... ... ...snip...
>
This WAS a discussion about grid current in grid-driven linear
amplifiers. The 8877 is not practicable in grid-driven linear amplifier
service. Apples are not oranges.
>Saying grid current always produces more IMD is a good example of
>distortion......... a distortion of fact.
>
I agree that this statement is a distortion of fact, Mr. Rauch.
- In a cathode-driven (Class AB2 G-G) config., grid current is essential
in order to be able to utilize the full emissive capability of the
cathode. However, in a grid-driven config., more grid current results in
more non-linearity. If this were not the case, we would see many tubes
rated for Class AB2 grid-driven linear amplifier service.
- How many tubes does Eimac rate for Class AB2 grid-driven linear
amplifier service?
Rich---
R. L. Measures, 805-386-3734, AG6K
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