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Old April 15th 15, 09:56 PM posted to rec.radio.amateur.antenna
Dave Platt[_2_] Dave Platt[_2_] is offline
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First recorded activity by RadioBanter: Dec 2014
Posts: 67
Default Good DIY antennas for 33 cm use?

I recently lucked into a bin-full of Kenwood TK-981 mobile radios at a
ham swap meet, and bought the lot. One seems to need a new final and
pigtail. The other four had "Works" notations on their yellow
stickies, and all transmit with a respectable amount of power.
Pending further testing I think I've got some useful kit here.

These are, of course, FM radios, mostly intended for repeater
operation. They also have simplex "talk-around" capability. Whomever
tested them, had cloned/programmed in a codeplug configuration which
seems to cover most of the West Coast ham repeaters and a few simplex
frequencies as well.

The likely use for these would mostly be as part of an emergency-
response kit, for helping set up command-net and message-net
structures during an exercise, drill, or an actual event. Due to the
scarcity of 33 cm radios I would not expect that many (if any) of the
individual ARES/RACES operators in our area would be taking part.

So... now I need to buy or make antennas for them. I'm interested in
ideas and suggestions.

I've seen a number of DIY designs on the net:

- Simple ground-plane antennas using an N connector and a few wires
soldered on are easy to make, and quite predictable. Unfortunately
the wires sticking out in several directions makes them not all
that "go-kit-friendly". I could figure out a design using (e.g.)
banana plugs and jacks to connect the elements, so the antenna
could be easily "unplugged and knocked down" for storage, but that
seems like a lot of fiddling.

- Several people have published designs for 33 cm J-poles, often with
a collinear structure for higher gain. Fairly predictable but
need some tuning during construction. Go-kit-friendly if installed
in a fiberglass or PVC radome tube.

- Simple sleeve dipoles (fold back the coax braid, trim for SWR,
heat-shrink) are easy, cheap, go-kit-friendly, and should be fairly
robust.

Yagis would also be useful but aren't as go-kit-friendly due to their
size; Kent Britain's "cheap Yagi" design is easy and the ones I've
made for other bands have worked well.

So, any other suggestions for simple-yet-effective DIY antennas for
this band? Are there commercial antennas good and cheap enough that I
should just buy a bunch? Good mobile antennas?