Sounds like 10 lbs of tripe.
Or, knowing Henry Radio, possibly 190 lbs.
The first amateur amp Henry ever built to cover 160m was the 3K Classic Mk
III using a single 3CX1200D7, in ~1986. I had to bully them into it, by
working with Ted S. (Shannon) Henry and giving him a cash-up-front order for
12 amplifiers. Ted told me they never added 160m to their amps because of
physical limitations, and how the enclosure would detune circuitry and
they'd never accomplish a reasonable Q, blah blah. I had already built a
4-1000A for 160 years earlier, on a much smaller chassis than the 3K, and it
had no problem delivering 1750W output with about 60% efficiency; I provided
Ted with the details of my circuit, which were largely lifted from an old
Radio Handbook. The amps were finally delivered about 4 months later, and
the 160m bandswitch position had been added, along with a huge piece of B&W
stock, padder caps (doorknobs) all over, a 160m tuned input, etc. The
resultant Q seemed reasonable, based on the half-power BW of the output
tank...tuned broadly and easily, and one setting would cover about 30 kHz on
1.8 MHz, not bad.
The _problems_ with that amp, which ultimately led to my selling it, were
acoustic noise (JT9D), too much time to make a band change (crank, crank,
crank, crank), and the silly roller inductor has a mean time to failure of
about a year or so of casual operating, before the contact jumps off the
track and wedges itself between turns.
WB2WIK/6
"Each success only buys an admission ticket to a more difficult problem." --
Henry Kissinger
> -----Original Message-----
> From: Doug Hall [SMTP:doug@nc.rr.com]
> Sent: Thursday, October 18, 2001 8:04 AM
> To: AMPS
> Subject: RE: [AMPS] Re: 8k ultra/ "tuned input"
>
>
> Rich wrote:
>
> > - Back in the days when Henry Radio did not build a 160m amplifier, a
> > friend dropped by the Henry Radio booth at a ham convention. He asked a
> > Henry engineer why they did not build a 3-500Z 160m amplifier. The
> Henry
> > engineer said that they tried it, but they discovered that 3-500Zs have
> a
> > cutoff frequency that's above 2MHz, so they don't work efficiently on
> the
> > 160m band. (sic)
>
> Rich,
> What was the name of the engineer who made this statement? Was he actually
> an engineer or just a sales guy doing booth duty?
>
> Doug, K4DSP
>
>
> --
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