Jim wrote:
You are not asking for the moon. What you want is a simple, compact,
reliable antenna for both 144 and 440 MHz.. Having done a fair amount of
that sort of RACES/ARES stuff, here's what I'd advise you.
Go down to your local radio parts store, Rat Shack if that's all you've
got
and get yourself a female BNC chassis connector (UG-1094, RS # 278-105).
Get a couple of quality male BNC cable connectors while you are at it.
Unfortunately for you, RS doesn't sell anything but that twist-on
solderless
crap for male BNC, so you may wind up buying them mail order.
Get yourself four 3/8" solder lugs and five 19" pieces of solid #14 copper
wire (strip house romex if you have to).
To each of the four solder lugs, solder one end of the #14 wire. These
will
be the four ground plane wires. THe fifth piece of #14 will connect to
the
solder cup on the bottom of the female BNC chassis connector to become the
radiating element.
Now put those four solder lugs over the radiating element and over the
threads on the connector. Use the nut that came with the connector to
fasten the solder lugs, each at approximately 90° from each other (a small
crescent wrench or dedicated 1/2" wrench needs to be part of your
permanent
tool kit). Bend them down at about a 45° angle.
Take the two male connectors and make an RG-58 cable to run from your
radio
to where you want to put your antenna. Connect one end of the cable to
your
radio and the other end to the UG-1094 connector.
You want to move the antenna? Disconnect the cable. Grab your wrench and
pull that nut off. Take off all 4 ground plane wires. Bundle them up
around the radiating element. Reassemble in the new location. Ten
seconds
up, ten seconds down.
You want to use it in the field outside? Bend a small hook (no more than
1/4" long) in the radiating element. Tie a roll of heavy twine to the
hook
and bend the hook shut. Take the roll of twine and throw it around the
highest tree limb you can find. Hoist that sucker up and you are on the
air.
We can dick around with a mounting bracket on the UG-1094 threads if you
want to make a permanent installation out of it.
(By the way, you are operating close enough to the third harmonic of 144
on
440 that the antenna will perform quite well on both frequencies.)
Jim
I agree -- Chuck isn't looking to work big DX so, a complicated antenna is
not needed. Another simple concept is a vertical dipole. Here's an
illustration from "Simple, Low Cost Wire Antennas for Radio Amateurs", by
William I. Orr and Stuart D. Cowan:
http://tinyurl.com/yzydbo
The bottom section connects to the shield of the feedline. If made from
tubing, it will act to decouple the outer surface of the shield. If cut for
144-148MHz (38-39" overall length), it will work at 432-444MHz as well. To
make it portable, use stiff wire (welding rod, etc) for the top half, and
schedule-40 ½" copper tubing for the bottom half. An insulated coupling can
be fashioned from wood or plastic dowel or plastic pipe. More dowel or
plastic pipe can be used as a carring handle. Like the ground plane, it can
be suspended from an overhead support. It can also be slipped into/onto a
baseplate if you don't have an overhead support available: nonmetallic
umbrella stand, heavy flower vase, etc. With the exception of the feedline,
your home improvement box store will have all the parts you need.
Bryan WA7PRC