On Thu,12/18/2014 1:18 PM, Doug Turnbull wrote:
I appreciate some guidance with this matter. I would like a
radial field which would take me to within 0.5/1 dB of the maximum
achievable for reducing near field losses.
Some of the best work I've seen published on this topic is by Rudy
Severns
On Thu,12/18/2014 4:59 PM, Ralph Parker wrote:
I have a 64' self-standing tower with a 3 el Steppir on it (insulated
elements) and a 40m linear loaded dipole (also insulated) on top of that.
I've worried that any high voltage on the ends of the boom might be harmful
to the drive motors in the dir
A few years ago, I put up a low, non-resonant dipole, about 150 feet long
and 10 feet high for use as an auxiliary receiving antenna on 160. My main
receiving antenna was and still is an array of short verticals. What I
found at my W1 location after I installed the dipole is similar to what N5IA
>>>My question is; If this is a contest inviting worldwide participation, why
>>>is there not at the minimum a full 24 hours of competition period?
Same questions from me and others UA0/RA0 Russian stations...
73! de Eugene RA0FF
http://www.qsl.net/ra0ff/
Thu, 18 Dec 2014 08:10:46 -0700 от "M
Concerning voltage breakdowns using yagi-loaded towers on 160 meters... I
have heard stories of arcing to beat the band, that included a fair amount
of destruction. I have heard stories of nothing needed for good operation,
even at QRO. All these stories have to exist in the same logical space.
A
Good question, Stan. I've wondered the same thing.
I have a 64' self-standing tower with a 3 el Steppir on it (insulated
elements) and a 40m linear loaded dipole (also insulated) on top of that.
I've worried that any high voltage on the ends of the boom might be harmful
to the drive motors in the
Preparations Under Way for January DXpedition to Iran
Preparations continue on the part of the Rockall DX Group to make Iran -- #33
on ClubLog's DXCC Most Wanted List -- available through a DXpedition to Kish
Island (IOTA AS-166). Look for EP6T beginning on January 16. While the emphasis
will be
Hello Doug,
The 50-60% figure depends on your soil conditions, so may vary quite a bit.
With my poor, sandy soil, the Vf is 67.7% with the radials laying on the
ground. When I buried them 6", the Vf was 39.8%. Using these shortened
radials, there wasn't much improvement going beyond 16 radials
Hi Doug,
As I understand it, the velocity factor of 50% applies for radial wires that
are simply laid atop the ground, & not buried in any way...
But of course, I COULD stand to be corrected..!
~73~ de Eddy VE3CUI - VE3XZ
On 2014-12-18, at 4:18 PM, Doug Turnbull wrote:
> Dear OMs and
Dear OMs and Yls,
I am replacing raised radials for 160M inverted L with ground mounted
radials mostly because I could not readily get the raised radials up high
enough in my wood and also because of maintenance problems.
This inverted L goes up 100 feet at its top before levellin
Jim
" What I am asking is if anyone has any, on-the-air experience and would
recommend one antenna system over the other for *most conditions*. In other
words, will an antenna that has a less lower elevation pattern generally
outperform an antenna that has a narrower beam width, but a higher ele
Judging from my own observations and feedback that I get I would say that
using a low dipole or horizontal polarity antenna would also depend on what
Latitude/Longitude your station is located and how close you are to the sea.
Here above 45 degrees Latitude and 200 miles from the sea, I seldom
" Since Rick correctly stated that RDF doesn't account"
Jim
RDF is everything ! The RX antenna system is the only way to improve
signal to noise ratio. All electronic device is not perfect and introduce
noise and deteriorate the signal to noise ratio, including your radio too
RDF is one way
Thanks JC,
I agree that the RDF number is significant when evaluating a receive
antenna. I agree that no one antenna system will work all of the time.
Consider we have two scenarios: One RX antenna system that consists of two
parallel antennas (Broadside) , and the other is the same antenna conf
" Since Rick correctly stated that RDF doesn't account"
Jim
RDF is everything ! The RX antenna system is the only way to improve
signal to noise ratio. All electronic device is not perfect and introduce
noise and deteriorate the signal to noise ratio, including your radio too
RDF is one way
Understanding what Bruce has posted would support the theory that a cage
feed tower is indeed fatter with a lower impedance and thus less
proclivity to arc over on the insulated elements.
Herb Schoenbohm, KV4FZ
On 12/18/2014 12:33 PM, k...@myfairpoint.net wrote:
One of the factors for arc
I'm considering insulating elements on large yagis and would like to
understand pro's and con's of various boom to element plate insulating
materials - RF insulation, physical strength, creep, uv resistance,
etc. These raw material properties are easily found, but have some had
longer term in
Not wanting to distract from this thread too much, but I'd like to ask a
question of the group.
If one had the opportunity to install two receiving antennas (such as loops
EWE's etc.) for Topband in either a series or parallel configuration, which
would be preferred. Since Rick correctly stated
One of the factors for arc over is the diameter of the tower and
top support pipe diameter & length.
A really FAT 1/4 wave tower may have 1000 ohms at the top, while a
skinny tower would have much more.
The higher the impedance, the higher the voltage to cause arc overs.
73
Bruce-K1FZ
Stan - For about 8 years, up until this past spring, my shunt fed tower
for 160 had a KT34XA (insulated elements, later upgraded to a KT36XA same
insulated elements) at the top and I never experienced any issue at all
running 1500 watts, even during a few contests where, as you know, you are
runnin
Milt,
Thanks to share with us your experience during XZ0A. When I started playing
with the HWF I was surprised to hear XU7ACY almost every day between 11:10z
and 11:20z SSW, during 2010 and 2011 , that happened 50% of the day from
October to April.
This kind of propagation I called it TELP, Tran
I once fed a tower with a klm 40m beam with an insulated DE on it with and the
coax taped to the boom. The insulation on the coax broke down and the coax
caught fire. I grounded the DE. Problem solved.
John K9DX
> Date: Thu, 18 Dec 2014 05:43:06 -0600
> From: wa5...@gmail.com
> To: topband
Vlad,
Although it is difficult to work Russian stations (UA0 excepted) from my
location in southwest USA, I find it very strange that the hours of the
contest operation do NOT include any night time hours at my location.
The sun sets at 0010 UTC at my location this time of the year. Conseque
Hi David and Don
I understand your point. Gain is cheap and quite easy to get with a good low
noise amplifier, but to keep the common mode noise out of it is very
expensive, and could be very complicated. The beverages are very forgiveness
and does not requires much amplification. It is an ideal a
Jim,
If the arrival angle of the signals is high, then definitely the low dipole
will perform stupendously.
At XZ0A in 2000 we were having trouble the first few evenings receiving
signals at our sunset and for a couple of hours afterwards. The Beverage RX
antennas were working very effectiv
I noticed JC's comment below about a low dipole as a receiving antenna.
Did I interpret that correctly? I've read of a Dipole on the ground as a low
noise receive antenna for 160 but.can a non resonant dipole installed
at low heights be better, as a receive antenna, than a vertical or
I have never had an issue with this on any tower I have shunt fed that had
a Yagi at the top with insulated elements, but then again my insulators are
probably a lot better than the average ones used on commerical antennas. I
am thinking about shunt feeding a tower that is not mine and wanted to k
Dear friends,
RUSSIAN 160 METER CONTEST will be held from 20.00 to 24.00 UTC, on the 19th
December 2014.
The Rules of the Contest are at
http://www.radio.ru/cq/contest/rule-results/index2012.shtml
Current Rules were approximated with RDXC Rules, and any RDXC software may be
used in this
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