It has been some years since I worked at ITT's Mackay Marine division. But I
know that back in the 80s there were a few commercial HF amps that were
designed to be driven by 100 mW exciters. Mackay (and several of the
competition) had an HF amp which consisted of a 3CX1500 driven by a
broadband solid state brick amp. The solid state amp was mounted underneath
the tube in the plenum assembly. A separate 2-30 MHz 100mW exciter drove the
thing and was mounted in the same rack. These things were mounted on ships.
Anyway, it would seem to me that a broadband solid state 100W PA (something
the CB crowd has had for years) could be used to drive a tetrode like the
4CX1600 (or one of the other Russian tubes) in grid-driven service to
provide a reasonably simple legal limit amp suitable for use with a 5W
radio. Of course it adds the complexity of a 15-20A supply for the solid
state amp, but switching supplies are lightweight and cheap these days.
73,
Doug, K4DSP
> At 12:02 AM 7/17/02 -0500, Mike Krzystyniak wrote:
> >I'm researching an amp project for a friend. He wants a legal
> limit or near
> >legal limit amp that can be driven from a Yaesu FT-817. It's
> been 25 years
> >since I rolled and amp so I thought I'd ask the gang here. Does
> anyone have
> >a suggestion for a tube or pair of tubes that when driven with 5
> watts will
> >run up to a KW out?
> >
> >Thanks... Mike K9MK/5
> >
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