[BC] Re: Unique VP-50

[Xmitters@aol.com]

In a message dated 1/2/06 5:09:48 PM Central Standard Time, 
broadcast-request at radiolists.net writes:

<< I never ran into a VP-50, but I did run into Ampliphasers.   How did the 
VP-50 work that made it unique?  Tell more.... >>

Conventional plate modulation (class B modulators, two 3CV30000H3 vapor 
cooled triodes), Vapor phase cooled. 7480 PA (which is a vapor cooled version of 
the 6697) Third harmonic resonators in the PA plate and cathode to significantly 
improve PA efficiency. So low power consumption for a conventional plate 
modulated AM.

 I heard, but not sure, but the VP-50 may have been Hilmer Swanson's first 
transmitter project when he thought, why do we have to keep building AM this way 
and he dreamed up PDM while on his lawn tractor mowing his lawn. The VP-100 
which was one more cabinet wider than an MW50, was the first PDM Harris 
transmitter 100 kW. I also heard that the VP100 (not the VP-100A) that was the 
prototype, was bought by the VOA and is still in Quincy in moth balls. Story had it 
that about every five years or so, someone at VOA would decide they wanted it 
and it would be set up and tested, only to be put into moth balls again. 
That's what I was told, who knows if true. Maybe I heard that on this very list, I 
don't remember.

Anyone know if it's still there? I would like to have it to experiment with 
on 160 meters if VOA does not want it. (my neighbor is a ham too so I can blame 
the interference complaints on him) If neighbors near me hear my 500 kW 
generator running, I'll tell them that I'm hot rodding my Chevy Blazer and doing 
engine testing. I need an excuse to go to Quincy anyway and have dinner at 
Sprouts (or The Pier) If the FCC comes knocking' I'm pleading insanity. Who in 
their right mind would run 100 kW on 160 meters?  I got it all worked out. What 
does Harris want with that old thing anyway?

Anybody seen the movie Power 98 about the late nite talk show host? I would 
swear that the transmitter room picture in that movie (which showed an AM-19 
and other actual working gear) looks like either a VP-50 or maybe a phasor built 
into the same kind of cabinets.


Jeff Glass, BSEE CSRE
Ham Call WB9ETG since 1970 (but maybe not for long if I get caught)