Re: Weird ideas (tube efficiency)

From: 	Jim Lux[SMTP:jimlux-at-earthlink-dot-net]
Sent: 	Wednesday, December 03, 1997 10:27 AM
To: 	Tesla List
Subject: 	Re: Weird ideas (tube efficiency)

>         Some of the big tube-type broadcast band transmitters ran
> at an OVERALL efficiency (power delivered to antenna divided by
> power from the AC mains) exceeding 90%.  It's no trick at all to
> design and build a Class C tube amplifier with 75% efficiency, and
> the filament/heater needn't use more than a few percent of the plate
> input power.

That last 15 percent (from 75 to 90) is a pretty big challenge though!