Andy wrote:
"John Livingston" wrote in message
...
Andy wrote:
I have managed to make an mp3 up. The first 10 seconds is on the Cobwebb
followed by another 10 seconds on the MA5B beam pointed in there
direction and then back and forth every 10 seconds. The click is the
antenna switch clicking over.

It can be found here.
http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b4.mp3

If anyone needs to here a clearer one let me know, but it will be best
after the contest has finished.

Andy
This sounds to me as if the MA5B has a very high angle lobe which the
Cobwebb may not. More galactic noise in proportion to the wanted signal?

John



Do you think the 2m/70cm collinear above the beam could cause this?

Andy

Quite possible. The influence of all large metallic objects in the near
field of the antenna will have a marked effect on the polar diagram. Try
removing the collinear to see what happens.

John

On Jul 27, 8:40*am, "Andy" wrote:
The beam is pointed in there
direction. The noise and signal increases every time when switching to the
beam.

http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b5.mp3

http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b6.mp3

I think your antenna system itself is probably normal for the
most part. I do hear some "whine" though on a couple of
them. Not sure what that is, could be puter/monitor related..
How is yours mounted? Flat horizontal? I had to look up a picture
to see what they are, and the one in the picture seemed to be
tilted. ? Maybe that was just to show up better in the picture..
As far as the static in the last one , it sounded like power line
noise for the most part. Either the antenna has a strong lobe
towards that noise source, or you have some noise around you
that is being piped up the shield. But almost sounded more
like it was received by the antenna to me. You should be
able to vary the level of the static, and maybe even find a
null of sorts if you turn the antenna. If not, I would look at a
possible ingress problem, and the noise coming from your
shack or house.
I checked the feed, and they seem to use a matching device,
feeding two elements. I assume they are probably feeding 10m
with a separate DE, or something along those lines.
I doubt this matching device deals with decoupling the feedline.
So the first thing I would do is make a choke out of coax.
You can use the feedline you have now, and just roll a
choke at the antenna end. 8 turns using a 6 inch diameter
coil. You can use tie wraps, tape, etc to secure the windings.
That should take care of most any ingress/common mode
problems, if you have any. At the least, should put a pretty
good dent anyway. If the noise is still strong with the choke,
it's probably normally received line noise, fence, etc in the
area. And other than turning the antenna, not much you
can do about that.
That you seem to have a normal match on all bands seems
to indicate to me that your elements, matching device, and
coax are all probably ok.
I strongly recommend adding the choke though, just to nip
the possibilities of noise ingress in the bud. Just one less
thing to worry about, and just that much less RF you will
have on your coax when transmitting.

Andy wrote:
I have managed to make an mp3 up. The first 10 seconds is on the Cobwebb
followed by another 10 seconds on the MA5B beam pointed in there direction
and then back and forth every 10 seconds. The click is the antenna switch
clicking over.

It can be found here. http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b4.mp3

If anyone needs to here a clearer one let me know, but it will be best after
the contest has finished.

Andy

Judging by the signal to noise ratio, it sounds like the beam is a
better antenna than the cobweb when it's pointed at the transmitting
station. You might be able to tell that more readily if you turned off
the AGC. You can even watch the AGC changing on the Windows Media
Player spectrum scope when you switch antennas.

Quieter antennas are usually quieter both ways.

ac6xg

I have taken down the beam and did a continuity test and re-checked that the
beam is put together correct and all seems to be ok.
Interesting about is could be power line noise. There are some over heads
street power cables close by that supplies power to the houses. Strange how
its just the beam that is effected by this. I have had HF verticals up here
before with no problem.
I have just laid my hands on a Timewave ANC-4. Using its own small antenna
it can cut out 80% of the noise but also cuts down the received signal to
less than being received on the Cobwebb. But at least its a good start in
the right direction. There was no manual with it. Any ideas on how to get it
working better would be appreciated.
I will let you all know how I get on.

73 Andy


"Jim Kelley" wrote in message
...
Andy wrote:
I have managed to make an mp3 up. The first 10 seconds is on the Cobwebb
followed by another 10 seconds on the MA5B beam pointed in there
direction and then back and forth every 10 seconds. The click is the
antenna switch clicking over.

It can be found here.
http://www.hobby.pwp.blueyonder.co.uk/ma5b/ma5b4.mp3

If anyone needs to here a clearer one let me know, but it will be best
after the contest has finished.

Andy

Judging by the signal to noise ratio, it sounds like the beam is a better
antenna than the cobweb when it's pointed at the transmitting station.
You might be able to tell that more readily if you turned off the AGC.
You can even watch the AGC changing on the Windows Media Player spectrum
scope when you switch antennas.

Quieter antennas are usually quieter both ways.

ac6xg

Andy wrote:
Interesting about is could be power line noise.

At my last QTH, the culprit on 40m was a ~33 foot
ground wire running down my front yard power pole
from a transformer and capacitor. It caused my
vertical to have 2 S-units more noise than my
horizontal dipole.
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:
Andy wrote:
Interesting about is could be power line noise.

At my last QTH, the culprit on 40m was a ~33 foot
ground wire running down my front yard power pole
from a transformer and capacitor. It caused my
vertical to have 2 S-units more noise than my
horizontal dipole.

Cecil;

Don't quit there!

Did you ever manage to have it "fixed?"

How did you manage it? Who did you report it to?

Thanks in advance,
regards,
JS

In article ,
John Smith wrote:

Cecil Moore wrote:
Andy wrote:
Interesting about is could be power line noise.

At my last QTH, the culprit on 40m was a ~33 foot
ground wire running down my front yard power pole
from a transformer and capacitor. It caused my
vertical to have 2 S-units more noise than my
horizontal dipole.

Cecil;

Don't quit there!

Did you ever manage to have it "fixed?"

How did you manage it? Who did you report it to?

Thanks in advance,
regards,
JS

Usually the your Electrical Utility, will have a supervisor in the
Distribution Department, that is responsible for dealing with
interference issues. Some utilities are more responsive than others.
When I lived down in the Flatlands, (Seattle, WA) Seattle City Light
had a guy that regularly meet with the local Interference Committee
which also included an FCC Engineer, the local ARRL Section Mgr, and
just about all the Marine and LMR Service Shops. He was also a Ham,
and used the information, developed by the committee, to track down
broken and failing insulators thru out their Distribution System.
The one outfit we could NEVER get to join the committee, was the
Cable TV Franshisee, and they generated MOST of the complaints.
Now I live out in the bush, and generate ALL my own power, so I am
the Utility, and I have to find and fix all the LF/MF/HF Noise if I want
to hear better. I usually have an MF/HF noise floor of less that 1.5
S-Units on my Kenwood TS690. I can hear, way farther than I can Talk,
due to the local Noise at the Receiving Station, masking out my
transmissions. It is frustrating to hear folks on 75 Meters with
S-7 Signals, but they can't hear me, due to S-9 noise at their end.

--
Bruce in alaska
add path after fast to reply

John Smith wrote:
Did you ever manage to have it "fixed?"
How did you manage it? Who did you report it to?

The power pole ground wire didn't appear to be
broken, just radiating like crazy. I managed
it by transmitting on the vertical and receiving
on the dipole. In the process of A/B comparisons,
I discovered that the vertical was never better
than the dipole and usually worse. The EZNEC
comparisons are on my web page at:

http://www.w5dxp.com/dipvsver.htm

To be fair, since receiving was limited to East/
West QSOs, the Extended Zepp beat the socks off
the vertical.
--
73, Cecil http://www.w5dxp.com

Aw, come on Cecil. You just didn't have the vertical oriented right.
Sort of tilt it in the right direction... you know?
- 'Doc


(Yeah, I know I'm gonna regret that, but I couldn't resist.)

Cecil Moore wrote:
John Smith wrote:
Did you ever manage to have it "fixed?"
How did you manage it? Who did you report it to?

The power pole ground wire didn't appear to be
broken, just radiating like crazy. I managed
it by transmitting on the vertical and receiving
on the dipole. In the process of A/B comparisons,
I discovered that the vertical was never better
than the dipole and usually worse. The EZNEC
comparisons are on my web page at:

http://www.w5dxp.com/dipvsver.htm

To be fair, since receiving was limited to East/
West QSOs, the Extended Zepp beat the socks off
the vertical.

On 40m, most run horiz. Horiz-to-horiz is always going to beat
horiz-to-vert.

Knowing you and your strong personality (at least from the news group) I
thought you might had been able to secure a fix from the power
companies' noise emissions. Was just wondering, and probably wouldn't
have helped with my problem anyway ...

Right now, I have an issue with a noise source I cannot even pinpoint
and is very broadband (and no, it is not BPL -- already ruled that out,
lol.) Noise is for blocks and remains fairly constant in strength.
This would lead me to think it was powerlines; however, the powerlines
are all underground! Which leads me to believe some noise IS on the
powerlines and the radiation is coming from the wiring in each
individual home/business. However, a scope, properly isolated and
hooked to my wiring doesn't give me a picture I can correlate to ... :-(

If it ain't one thing, it is another ... keeps life interesting, I guess.

Regards,
JS