A-4S Issue
 

My A4S is acting wierd and I cannot figure it out.

20 meters its got great SWR. 15 is so so but tunable with a tuner
and stays relatively flat.

However 10 meters, the SWR stinks and I can try to tune it with a tuner
but then it goes out again. And I can swing the beam and hear the
Noise pick up and go down with the turning of the beam and when it stops
it wiggles a bit and the SWR changes. The tube and trap connections all
see secure.

Do I have a bad trap or ?????


Scotty W7PSK

A-4S Issue
 

On Nov 15, 12:43*pm, "R. Scott" wrote:
My A4S is acting wierd and I cannot figure it out.

20 meters its got great SWR. * 15 is so so but tunable with a tuner
and stays relatively flat.

However 10 meters, the SWR stinks and I can try to tune it with a tuner
but then it goes out again. *And I can swing the beam and hear the
Noise pick up and go down with the turning of the beam and when it stops
it wiggles a bit and the SWR changes. *The tube and trap connections all
see secure.

Do I have a bad trap or ?????

Scotty W7PSK

Do you have the water drain holes pointing down?

A-4S Issue
 

First thought is a 'not good' electrical connection somewhere. A
'joint' may seem secure but be a bad electrical connection. No idea
if you have a bad trap. Making sure that they are not filled with
water or whatever else would be a good idea (drain holes pointed
down??). I would think that having to use a tuner means that maybe
the antenna isn't adjusted correctly? If you can get it to a point
where you can do all that checking of joints, etc, why not just take
it apart, clean it, and put it back? (Easy for me to suggest, I ain't
the one doing it, right? ;))
- 'Doc

A-4S Issue
 

"R. Scott" wrote in message
...
My A4S is acting wierd and I cannot figure it out.

20 meters its got great SWR. 15 is so so but tunable with a tuner
and stays relatively flat.

However 10 meters, the SWR stinks and I can try to tune it with a tuner
but then it goes out again. And I can swing the beam and hear the
Noise pick up and go down with the turning of the beam and when it stops
it wiggles a bit and the SWR changes. The tube and trap connections all
see secure.

Do I have a bad trap or ?????

Coax connectors or water intrusion are often a problem.

A-4S Issue
 

R. Scott wrote:
My A4S is acting wierd and I cannot figure it out.

20 meters its got great SWR. 15 is so so but tunable with a tuner
and stays relatively flat.

However 10 meters, the SWR stinks and I can try to tune it with a tuner
but then it goes out again. And I can swing the beam and hear the
Noise pick up and go down with the turning of the beam and when it stops
it wiggles a bit and the SWR changes. The tube and trap connections all
see secure.

Do I have a bad trap or ?????


Scotty W7PSK

I have an A3S (a similar design). It sounds to me like either...
1) oxidized connection(s) between tubing section(s): disassemble, clean and
reassemble tubing joints.
2) moisture inside a trap(s): remove trap(s), drain and "bake" the moisture
out, and reinstall with drain holes pointing DOWN.
3) a bad 15m trap (actually resonant on 10m): replace if resonant frequency
is not approximately 28 MHz.

Bryan WA7PRC