Oops -- some clarificaton needed.
The load is 50 ohms, non reactive.
The coil is 3/8" tubing, not 5/16".
Sorry for the confusion. 73, Arliss
Rich Measures wrote:
> >I think the efficiency of my homebrew 6m 8877 amp is
> >lower than it should be (currently about 50 %), and am
> >looking for some suggestions on how to improve the
> ? What is the resistance of your termination R when measured with a DMM?
> >The amp runs about 2800 V key down at 1 amp, with 50 mA
> >of grid current, into a 50 ohm load. Idling current
> >(set with a 12V Zener) is about 75 mA. The plate
> >circuit is a Pi-L network patterned after Lauren Libby's
> >(W0LD) HR article from July 1986, using a vacuum variable
> >tuning capacitor, 3/16" copper tubing for the coil,...
> ? Due to skin effect, the circumference of conductors needs to be
> greater as f increases. IMO, for good tank efficiency, 3/16" tubing is
> ok for an 8877 on 160m. For 10m, it is not.
> - later, Arliss
> R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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