- Forwarded Message
From: George Badger [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Monday, November 3, 2008 7:26:13 PM
Subject: Fw: [NCCC] Sunspots and SS
- Forwarded Message
From: George Badger [EMAIL PROTECTED]
To: R. Dean Straw [EMAIL PROTECTED]; James Michener [EMAIL PROTECTED]
Cc: NCCC [EMAIL PROTECTED]
Sent: Monday, November 3, 2008 7:08:30 PM
Subject: Re: [NCCC] Sunspots and SS
Dean
Like insulated wire, SteppIR elements are well enclosed in dielectric tubes so
they may not suffer from precipitation static. Can anyone confirm this?
73
George W6TC
- Original Message
From: R. Dean Straw [EMAIL PROTECTED]
To: James Michener [EMAIL PROTECTED]
Cc: NCCC [EMAIL PROTECTED]
Sent: Monday, November 3, 2008 1:40:36 PM
Subject: Re: [NCCC] Sunspots and SS
Jim:
I've heard anecdotal reports that Beverage antennas made of insulated wire
work better than Beverages made with uninsulated wire. Just because the
reports are anecdotal doesn't mean that they are untrue, of course. When I
had a station in New Hampshire, I made my Beverages with insulated wire. The
Beverages worked in a predictable fashion on 40 and were worse, pattern
wise, on 20. But they were definitely quieter than the Yagis when there was
precip static going on. So the SNR was better for receiving.
I would think that insulated-wire Yagis would be better for precip than the
usual bare-tubing Yagis. That seems to be the conclusion you're coming to
also. And yes, the top Yagi in a high stack acts as a precipitation drain,
shielding the lower Yagi(s) some. Even a snake kind of antenna, with
insulated wire lying on the ground (as W0YK mentioned), can help reception
when precipitation static is happening.
I'd caution you that if you live on a hilltop, placement of the your
antennas compared to the upslope(s) to the hilltop can make a difference in
precip problems. At one time, I lived on a tall hill in San Francisco, with
about a 45 degree slope downwards in the south direction. Storms would come
up from the south and swirl winds violently up that slope, hitting the
antennas from below and creating real precip static (as well as breaking
lots of antennas -- ask W6NL about this too). I didn't have the luxury of
having another antenna on my small lot. But if I did have another antenna
and if it were located back from the slope I would imagine that it would be
better in terms of precip static.
So, the difference between your dipole and the wire Yagi may also involve
placement on your terrain, as well as the use of insulated wire. These
things get complicated.
I've been in whiteouts in southern New Hampshire, but nothing like what you
get in/near VE2. I remember disconnecting coaxes and hearing the arcing
inside the PL-259s when precip static was going on.
73, Dean, N6BV
-Original Message-
From: James Michener [mailto:[EMAIL PROTECTED]
Sent: Monday, November 03, 2008 12:53 PM
To: R. Dean Straw
Subject: Re: [NCCC] Sunspots and SS
It rained here hard all Saturday night. I have wire antennas. The
40 meter 2 element beam. The DE is a folded dipole and the Reflector
is insulated wire at about 60 feet. The other an 80 meter cage
dipole made with multiple #12 AWG not insulated copper weld wires at
about 100 feet. They are not at all close together. Both are fed
with open wire and both are tuned with (separate) old KW Johnson
Matchboxes. The rain static noise on the dipole was awful. The 40
meter beam didn't any problems. I wonder how much having an
insulated antenna helped in keeping down the rain static. I did
more contacts on 80m in the final hour than I did Saturday night...
(I gave up early Saturday night due to the 80m static.)
With vertically stacked Yagis, this top antenna can acts as a static
drain... In my case with 100 feet of horizontal separation, there is
little static draining effect... so some of the difference was
height... but some of the difference maybe insulation.
I thought the difference was largely due to insulation and not
height... but I could be wrong.
BTW... I went to college up near Quebec and when they get a dry snow,
you have never heard static so bad. It wipes out local 50KW AM
stations. There isn't insulation thick enough that would help. I
had a 2m whip on the car and the static would arc the coax while
corona balls jumped off (or on) the end of the whip. You really
shouldn't be driving in that, since it was a white out.
Jim K9JM
At 11:55 AM 11/3/2008, you wrote:
I wasn't talking about powerline interference when I spoke about
precipitation static. The noise comes from the electrical charges on
individual raindrops (or snowflakes) in a storm. These raindrops
discharge
when they physically strike your antenna. At K6TA, which is located on a
hill, the precip static was often S9 + 20 dB and would typically
last for 10
minutes or so before gradually fading down. Then the next wave
of rain would
come
