>
>Hi folks,
>
>Doing some tinkering here, I worked out a polynomial based on
>Eimac's GG constant current curves for the 8877 to calculate static
>plate current based on a given bias voltage. Does anyone have
>any data they'd be willing to share based on real measurements?
>I'd like to check my work, to see how far off it might be from
>a real case. The Eimac data is spotty at higher plate voltages,
>(thus not a lot of points) although the curve fit seems pretty fair.
>
>Here's a sampling, based on a constant plate voltage of 3900:
>
>Bias (V) Plate (ma)
>------------------------
>19.4 Cutoff
>18.0 18
>17.0 33
>16.0 51
>15.0 70
>14.0 92
>12.0 142
>10.0 198
>8.0 262
>
>Does this look anywhere close to real?
>
/ As I read it, 8.2V of cathode-grid bias produces c. 185mA of ZSAC.
However, even at 90mA of ZSAC, an 8877 is so much cleaner than today's
transceivers, it would make
virtually no audible on-the-air difference in IMD.
cheers, Jim
- R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
end
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