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[3830] ARRLDX CW K5GO M/M HP

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Subject: [3830] ARRLDX CW K5GO M/M HP
From: K5GO@ALLTEL.NET (K5GO@ALLTEL.NET)
Date: Tue, 20 Feb 2001 13:31:59 -0500 (EST)
                     ARRL DX Contest, CW
                    
Call: K5GO
Operator(s): K0RWL, K0VBU, K5GO, K5LG, KJ5WX, KM5G, N0EHW, N5DX, N5OE, W0JOE, 
W5RZ, ALSO K5ALU, K0DEQ (IN SPIRIT)
Station: K5GO

Class: M/M HP
QTH: AR
Operating Time (hrs): 48
 

Summary:
 Band     QSOs  Mults
----------------------
  160:     79     39
   80:    173     62
   40:    857     96
   20:    967    117
   15:    936    104
   10:   1472    108
----------------------
Total:   4484    526  =  7,075,752

Club: Ozark Contest Club

Comments:

Following is a long story describing an unusual weekend for us on the mountain:

The day before the contest everything was set up and working as it should. Upon 
arriving at the site a couple of hours before the contest I found that the 
weather on the mountain was a little different from the cool, crisp afternoon 
downtown.  ICE was forming on everything.  I checked the SWR on the antennas 
and they were high but perhaps usable. In an attempt to keep things moving I 
rotated all the antennas about every 10 minutes.  

Everyone showed up about 30 minutes before the opening bell.  It was then that 
we discovered that the 5L48 20M yagi at 120' was completely dead.  The only 
other 20M antenna was a four element job at 60' pointed toward JA.  Also the 
15M yagi had an SWR that measured about 25 to 1.  SWR on 10M and 40M was 
"great" - 2-1 and 4-1 respectively! At that point in time I was considering MS 
or M2, but N5DX talked me out of it. We had imported K0RWL for 20M and K0VBU 
for 10M from up north and since Kevin was the designated 15M operator and was 
willing to give it a go, with an antenna that produced question marks from JA's 
that would probably have been twenty over nine on a good antenna, I agreed to 
enter MM as planned. 

A Matchbox was placed in line on 40M to make the amplifier happier and the 
contest began.  An hour into the contest we had a total of 128 contacts in the 
log and at the end of the first night, we had a total of 34 contacts on 15 and 
50 contacts on 10M.  With 160-20 still "going strong" we had time for a few of 
us to contemplate our problems and look for solutions.  

The questions and answers:

What was wrong with 10M?  SWR with the ice was only about 2 to 1 and only 50 
contacts in the log for the first night.  The band should have been good enough 
to run JA stations at a rate of 100 or more per hour. The answer was that mast 
was iced to the thrust bearing and top of the tower and had stayed stationary 
while the antenna was initially rotated. We were off 60 degrees and beaming 
Europe.  Easily compensated for before the next morning as the antenna was now 
turning.

What was wrong with 20M Yagi?  Surely 3/8 inch of ice wouldn't create a TOTALLY 
dead situation. The answer was that the next day in the daylight K0RWL saw the 
coax sticking out from near the top of the tower.  Iced up limit switch on the 
Telrex rotator had failed while I was running around the room turning antennas 
before the contest and coax was broken in the loop at top of tower.  Weather 
forecast was for sunny and about 45 degrees - enough to melt some of the ice 
off the tower.  Shaking guy wires helped shuck some of the ice off the tower 
and it was pretty clear up to about 100 feet.  Hammer in tow, up the tower I 
went with a roll of electrical tape to do the temporary splice job.  Hammered 
the ice off the rungs one at a time and got the antenna to work about 23:00Z on 
Saturday..

What was wrong with the 15M antenna?  The 10M yagi SWR had only climbed to 2 to 
1 with all the ice and yet the 15M yagi had an extremely high SWR. The answer 
is still not known, but a broken center conductor from the 75 ohm coax (jumper 
to the hardline) iced to the tower is likely.  KM5G climbed the 15M tower on 
Saturday and used a log piece of PVC to de-ice the elements to no avail. 
Realizing that Kevin would have no fun and the amplifier didn't like the high 
SWR we brainstormed ideas for something with gain that could be put up in the 
middle of the night without climbing an icy tower.  Ideas included de-icing 
three sections of 25G, building a yagi and putting it all up at 4:00AM all the 
way down to making a dipole and putting it up 15 feet between a couple of 
trees. K5LG (a guy who is always thinking) came up with the best idea - A 
vertically polarized wire yagi stretched between a rope on the 10M tower and a 
tree.  We would have to use RG-58 coax from the feedpoint to the ground in 
order to not weigh the thing down. Fifteen minutes after his idea we YO'd a 
design for a 5 element yagi with 50 ohm impedance optimized for CW band with a 
prejected gain of about 9.5 DBI gain and flat SWR curve (pretty much needed in 
order for the RG-58 to survive the legal limit we planned to deliver. N5OE, 
KM5G, N0EHW and I went to work to cut the elements to length and make loops in 
the top rope and in another rope on the bottom to hold the elements in their 
proper places. About 25 feet of RG-58 was coiled up for an RF choke and the end 
was barrel connected on the ground to RG-214 and then run to the amplifier.  
The top of the reflector element was at about 50 feet and the bottom of the 
third director was at about 10 feet.  It was pointed down, but it looked 
"professional." The antenna was rotatable from Europe to JA by moving the end 
ropes to different trees. Antenna was built and put up by 4:00AM in 10 degree 
weather (they always work better when the weather condx are bad) and we came in 
to try it out - Get this...1400 watts forward and 1 watt reflected at 21.025!  
Thanks to K6STI! Final results on 15M with this rather simple antenna only 
pointed in one of two directions - 936 QSOs and 104 countries! You know when a 
couple of HS0 stations answer CQ's over Europe that the antenna is working! 

Shunt fed tower works very well on 160M, New Bobtail curtain on 80M seemed to 
work pretty well. Computer network, thanks to W0JOE, works perfectly all the 
time. 


Final results were that everyone worked really hard, had a good time, and set 
an ALL TIME RECORD FOR ARKANSAS in the multi-multi category :)... I can't think 
of anything more we could ask for!

Stan, K5GO         


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