On 22 Feb 2005 10:41:15 -0800, "dave.harper"
wrote:


Buck wrote:
On 22 Feb 2005 06:38:53 -0800, wrote:

I'm tracking a high altitude balloon on 2m via a handheld scanner,
and
in the past have used the standard rubber-duck antenna that the
scanner
came with. However, reception isn't too great at times. What kind
of
gain increase could I expect to see if I were to replace the current
rubber-duck antenna with a quarter-wave antenna (designed for 2m and
70cm)?

Significant. I don't have a number, but it will definitely improve.


On the balloon, is the antenna vertically polarized? I would assume
so. If not, consider a dipole.

Also, to improve the reception further, build a 'rat-tail'. Its a
1/4
wave wire that hangs from the ground of the rig making your 1/4 wave
antenna more of a 1/2 wave. You may find adding that will help even
with the duck.

Really? Any point on the ground? Or does it need to be connected
somewhere on the antenna?

Thanks for the advise!
Dave

most commonly they are connected to the bnc ground, but anywhere that
is grounded to that connector will work. Since this is a scanner, you
might consider a piece of computer ribbon cable. Cut each wire in the
ribbon to 1/4 of your favorite bands or frequencies until you run out
of wire. If you have left-over strips, just remove them or leave them
for later use.

Just a thought.

Buck

--
73 for now
Buck
N4PGW