[AMPS] 8877 bias curve?

[Phil Clements]

Subject: Re: [AMPS] 8877 bias curve?


> >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?

Looks really close to me, Jim.

> >
> /   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.

I agree, Rich. When running an 8877 at the full 4KV, I have always
used 12 volts of bias to cut the heat in the shack down a bit. I doubt
if there is any measurable difference in feculence.

(((73)))
Phil, K5PC




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