Having gone through a similar process over the last couple of years, I have
some strong feelings about this question.
I assume that you are interested in contesting :-)
Your number one issue is antennas. They help on both send and receive. If
you are using a small trapped tri-bander like a TA-33jr, the first thing
that I would do is upgrade to something like a C-3E from Force 12. No
traps, highly efficient, good gain on each band. Check out the tribander
comparison report from Champion Radio.
The next thing I'd do is get that antenna up higher. 30 feet is way too low
for 20 meters. You can pick up a used 50 foot tower for not much - it will
cost you something to get it installed, but you should be able to put in a
decent 50' crank-up with a 10' mast (60' total height) for under $1,000 all
in if you scrounge for a good used tower.
The next thing I'd do is upgrade your amp. Get a good SB-220 or one of the
4x811 amps. You should be able to find one in very good shape for $600.
For contesting, if you like high rate, you need at least a kilowatt of PEP
output. If you enjoy low power or qrp, then sell the amp and use the money
for one of the other items.
The last thing I'd worry about is the radio. I swapped my older rig for a
TS-850. They are great contesting radios, and available used for $800 in
good condition. The '850 has a great receiver, and a computer interface.
Add a set of Inrad filters when you can afford them.
Bottom line - don't try to do it all at once. If you can spend $100 per
month, you can make a big difference over the course of a couple of years.
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