At 04:42 AM 8/12/97 -0800, you wrote:
>My copy of *Care and Feeding....* does not appear to contain such curves.
Please go to www.eimac.com/c&f.htm and read what it says. Too much for
me to retype.
>
>IMO, there is no direct relationship between anode current and grid
>current. According to the characteristic curves for the 8877, grid
>current is primarily a function of minimum anode voltage during the
>conduction half of the cycle. Significant amounts of grid current do not
>flow until the anode voltage decreases to under 900v.
At a constant current, Ep and Eg vary with time. By plotting along the
chart with the operating values we are interested in, we establish what
is known as the "operating line." The use of a DC amp meter from B- to
ground in a GG amp allows us to monitor the complex goings-on at the
grid, and keep it from being used as an expensive dummy load.
>If this be the case, then why doesn't Eimac specify a maximum DC current
>rating for the 8877's grid?
Because the DC component is such a small portion of the total Ig it would
never be the prime limiting factor.
(((73)))
Phil, K5PC
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