Aloha and have a great 1998!
Let me first introduce Vance Friend, KH6JAW.
Vance has long been out here in the Pacific. Was on Guam
for many years. He is now nearly 82; he and his wife make
music at various Hawaiian VFW events, among others. Vance
plays the slack key guitar, an old Hawaiian tuning method
they preferred long ago to the traditional Western tuning
scales. Vance's wife plays the keyboard.
Now Vance was a technician type in the service, working
on radios, radars, nav gear, all the usual stuff.
Shortly after his 81st birthday last year, he decided to
build up, what he called, " a new afterburner" for his
rig.
He had a couple Hawaiian Electric Co. pole transformers and
various odds and ends, such as we all have, accumulated over
the years. This included some 30+ year old 4-400 tubes.
First he built up the power supply using one of the pole
transformers in reverse; he got about 4000 volts DC that
way. He went to work on the amp next. At the semiannual
QCWA meeting of the Hawaiian Chapter last October down
in Hilo Town, Vance was showing off his amplifier blower
cooling assembly. He had scavenged the blower from an
old microwave oven, and fashioned a new shroud for the
assembly, as in the oven the back plate forms part of
the blower set up.
He disassembled one of the pole transformers, as he wanted
the "wire" from it for his amp and power supply. The wire
actually looks more like buss bar, real heavy conductor stuff,
and the transformer contains hundreds of feet of the stuff.
However, and this I could not believe anyone would do,
Vance used RG8 through out the amplifier in the RF circuit
sections!!
About this time, late Summer, I was in the middle of my V-beam
set up project, and had found an old E F Johnson kW Matchbox someone
had for sale and ported on the .swap news group. So I made an offer and
bought it. It didn't seem to operate just right, so Vance suggested
he ought to have a look at it. I sent it down to him, as he lives
in Pahoa on the Big Island. He dug right in, and found that only about
1/3rd of a first turn of the primary/link coil was being used.
Someone had tried to modify it, and evidently did not get it right!
Anyway, about this time "LB" Cebik, W4RNL (see his web pages:
http://funnelweb.utcc.utk.edu/~cebik/radio.html) began posting thoughts
about link coupled antenna tuners on the towertalk reflector. Vance
and I soon decided the Matchbox ought to be brought up to LB's spec ideas,
including adding a primary circuit variable C, and tapping the
primary link coil at several turns for optimum matching. Vance
offered to do the mechanical work, and I located the components
for the update; most came from Surplus Sales of Nebraska, where I
found Johnson type caps, etc. Vance then split his building time
between his afterburner and the Matchbox rebuild. He found the
Matchbox had been owned by a smoker, as it was really coated on
the inside with ick. He completely disassembled and cleaned
everything to look as new. Then he told me he was re-wiring it
with RG8!! Oh well, we will see how it works! He is till fooling
around with it. He has also found that the magnetron filament by-
pass capacitors from the microwave oven are about 500pF, and
might be useful in the tuner update! I cautioned that
they might not have the current carrying capacity needed in the
tuner primary series circuit, but we will see about that also.
By early December, Vance introduced his afterburner performance on
the Hawaiian Afternoon SSB net, meeting at 0200Z on 7088, an
allowable SSB area out here in the Pacific. It performed very
well. However, just a couple of weeks before Christmas, and
probably with only a few hours use, one afternoon his signal
became strange, then vanished! He came back up, barefoot, and
announced that one of the 4-400's has gone SWOOSH and died. His
voice ached with disappointment. One of his decades old tubes was
gone, and so was the usefulness of the amplifier along with six
or seven months of work.
Later, I got to thinking about what Vance was doing gratis for me
rebuilding the Matchbox. So I posted a short note on .swap group
wondering if anyone had a pair of 4-400's. Almost immediately I
began to receive responses. There seemed to be plenty out there!
(Three weeks or more later I am still receiving offers of tubes).
I quickly decided to get a pair from Harold, W4PQW down in
Pensacola, he asked a very fair price and even offered to pay
the shipping to Hawaii -- that later turned out to cost
$52 UPS Blue, so we shared the cost!.
I got the tubes just afetr Christmas, checked them over. Looked
to be absolutely new, unused Eimacs. If I read the date code
correctly, they are dated 9618, which I take to mean the
18th week of 1996, just about the time Eimac was getting ready
to close down the glass tube fab operation. So Harold seems to have
supplied what he offered, new Eimacs, a pair of 4-400A's.
I sent them on down to Vance. He had no idea they were coming.
They arrived yesterday, mid afternoon. You should have heard
Vance, with the afterburner flaming away on the Afternoon Net.
His voice was choked with emotion and gratitude for the tubes.
I tell you it made my Christmas season for me all over again.
Ever hear a guy nearly 82 years old almost cry?
What a thrill it is to do something nice for a friend, and have
it so warmly and joyously accepted and appreciated!
73, Jim, KH7M
On the Garden Island of Kauai
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