>> Why would one need to tune for grid-current ? Minimal grid current does
>> not give a correct tune. Maximal grid-current does not give a correct
>> tune. A correct tune is max out with the drive needed to produce 1A of
>> anode current per 8877 -- which coincidentally results in c. 100mA
>> grid-current per grid, which could be seen on a 0-500 scale. However,
>> there is no need to measure grid-current on a cathode-driven amp.
>> Grid-driven, yes.
>
>When I tune an 8877 amp, I tune everything for maximum power out.
>I then tweak the PA loading cap slightly to give a needle-width decrease
>on the wattmeter. I need to see the grid current at this time to make sure
>it goes down and not up when making this adjustment. This slight reduction
>in suds makes a nice increase in clean.
True, Phil, but the 8877 is so clean that there are no transceivers even
in the same league.
>...
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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