Several people have asked how the 1920's TopBand ham station is coming.
Yesterday I completed the much-needed Beverage receive antenna. I haven't used
Beverages before because I only have one possible location on my property, and
that is towards Northern Europe. The problem is that it requires carving a
tunnel through an ugly Cedar swamp. Winter is the only time you want to be in
there. It cost me a chainsaw, but I now have 500' of #14 THHN strung out, 30"
high. I was amazed when the analyzer said that it is one wavelength long at
1840 kHz, so I guess it meets the classic definition of "1 wavelength or
more..". I built a vintage preamp, but the gain was not necessary, and would
overload the regenerative detector if left in. The existing screen-grid UX222
rf amplifier provides plenty of adjustable gain.
I was hoping that last night would have good conditions & was not disappointed.
I called CQ DX a number of times on 1837 (crystal controlled) & was finally
answered by Tony G4ZCG. It was a FB qso, but I don't know if my "rig is 1929"
comment registered. Thanks, Tony, for Trans-Atlantic #2 on the vintage rig (#1
was F5IN). Later in the evening when things thinned out a bit, I got brave and
plugged in the 1828 crystal. There I worked Kent SM4CAN, who had a very strong
signal on the regen. Later I went back to 1837 where Tom OH2BEN was cq'ing. He
came right back to my reply for another successful completion. Thanks guys!
I originally embarked upon this 1920's vintage quest just to see if I could
work across the Atlantic, but the station is taking on a life of its' own. I
even started a new ARRL logbook just for the vintage station, and have 4 qsos
so far, with 4 different European countries. Things are getting
interesting....I intend to have a photo QSL made up showing the rig, and every
QSO will get one.
One humorous observation was made concerning vintage test equipment. When the
beverage was up, I wanted a resistance measurement on it, to be able to test
integrity without having to go back in the swamp again. I recalled a recent
posting where someone mentioned doing the same on his Beverage & it came out
20K ohms. This struck me as rather high, but as I'd never had a Beverage I
wasn't sure. With a 260 ohm termination, 500' of #14, and a ground rod at each
end, I connected up my new digital DMM and read 0.0 ohms! I looked around for
the obvious short, but it wasn't there. I went back to the shack & brought back
three more DMMs, 2 digital LCR meters, and an old battery multi-meter. Each
piece of digital gear gave a widely different, ranging from 0.0 ohms to (-) 1.8
Megohms! One meter never would settle down. Keep in mind that this was done in
mid-day, and you can't find a decent signal on the AM radio during the day up
here in the center of the Upper Peninsula of Michigan. I
then connected my trusty Triplett 310 multi-meter (which I've had for
decades). On the RX1 scale, it read a stable 560 ohms. Sounds about right. Even
this battery multi-meter got less accurate on the higher resistance ranges, but
nothing bizarre like the digital units. So, old vintage gear wins out again.
I'm tempted to take the "B" battery out of the receiver, connect it to the
Beverage, and measure the resulting current with an old Weston meter. This
should give an even better signal-to-noise ratio. Back-to-basics can be
fun...and educational.
Brian
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