It is Tuesday and that means that there will be all sorts of activity on
222 MHz. If you want to check out the latest update to your 222 setup,
tonight is THE night to check it out. KA2LIM in western New York will be
checking out some mods that he made, and I will be trying out version 3
of my high voltage power supply. Version 1.0 was just ugly and crude.
Version 2.0 was very pretty and used 12 X 2200 MFD 550 volt electrolytic
capacitors in a big capacitor bank. After having a very robust arc
event that took out my HV fuse, I calculated the energy stored up in
those capacitors, and decided that I had gone overboard a little bit. I
mean 183 MFD at 5500 volts does seem a bit big! 1600 joules of energy
is not trivial. I also had a failure of one of the 12 equalizing /
bleeder resistors, and that got me to thinking that using a bunch of low
voltage capacitors in a high voltage power supply was not a good idea.
Yeah, I know, everybody does it, but I felt more comfortable having a
single high voltage rated capacitor and a honkin' 200 watt wire wound
bleeder resistor. Hence Version 3.0! I now have a 30 MFD at 5 KV non
PCB capacitor installed along with an 80 Kohm 400 watt bleeder
arrangement all set for this evening on 222 MHz.
Yes, I know that there are many areas of the country where activity is
rather sparse. All it takes is two stations to get on and make a
contact. With the availability of chat pages now, it is a simple matter
to find someone at a suitable distance and try a difficult sked over an
un believable distance. You might surprise yourself. I know that
Marshall, K5QE (Bless his soul) gets on for Tuesday night, and has no
local activity, so he tries to drum up a meteor scatter, EME, or tropo
scatter sked every Tuesday. We need many more stations to be active in
out of the way places to try to extend our collective range. This is how
we can maximize our stations. Try something difficult! 900 miles is a
good meteor scatter distance. Tropo scatter can work out to 400-600
miles depending on your station and whether you can catch a tropo peak.
Last week, I managed to work KO4YC at 525 miles while running 80 watts
here. I don't know how Cornell managed to copy my flea power, but he did!
I will be QRV at about 7 PM (2300 UT) on 222.1 or thereabouts. Try to
make an appearance and make a contact or two. It should be showery along
the East coast, so it is a good time to be inside and on the radio.
Dave K1WHS
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