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[3830] 7QP K4XU SO MobileCW LP

To: 3830@contesting.com
Subject: [3830] 7QP K4XU SO MobileCW LP
From: webform@b4h.net
Reply-to: k4xu@arrl.net
Date: Tue, 07 May 2019 05:04:02 +0000
List-post: <mailto:3830@contesting.com>
                    7th Call Area QSO Party - 2019

Call: K4XU
Operator(s): K4XU
Station: K4XU

Class: SO MobileCW LP
QTH: Oregon
Operating Time (hrs): 17

Summary:
 Band  CW Qs  Ph Qs  Dig Qs
----------------------------
  160:                   
   80:  171              
   40:  327              
   20:  337              
   15:                   
   10:                   
    6:                   
    2:                   
----------------------------
Total:  836     0       0  Mults = 55  Total Score = 145,290

Club: Willamette Valley DX Club

Comments:

Things started off very slowly. 20m was not open at 6AM local. 40m was the go to
band until well after 8AM. 20m never really produced as it has in past years.
Virtually no DX, nil from the east coast until way after noon, and it closed as
soon as the Back East crowd could use 40m. 15m was a non-starter.

This year I could not find a driver. Except for Charlie, KI6Y (SK), nobody who
has driven for me in the past has ever volunteered to do it again. I can't
imagine why.... So this year I did a solo route again, all in Oregon. It's a 512
mile circular route covering 11 counties in Central Oregon's high desert. I
posted the route and schedule on the N7XU QRZ page. It’s no fun going solo and
potentially dangerous. I can copy and send CW in my sleep, but multiplexing that
while driving at speed, usually 9mph over the limit, is taxing. You have to
forget about logging so I did. A simple splitter in the headphone line sends
audio to a small Olympus digital recorder. One problem is keeping track of what
band you’re on, helped by the TS480’s band change beep and a paper list kept
when changing antennas. The other is you must endure the entire contest over
again without scenery while transcribing the recording into N1MM. There ought to
be a way to couple something like Skimmer with N1MM to automate this task but it
eludes me.

For the past 10 years I have used a Hustler 40/20/15m pitchfork mounted on the
rear fender of the Jetta. Doing some modeling based on accurate physical
measurements of the Hustler coils, I was blasted by the inefficiency of this
setup. On 40m, the antenna efficiency is just 18%. This is neglecting ground
loss. EZNEC calculates efficiency as 1- PLoss/PIN. That is -7.5 dB! 20m was a
little better at 52% and 15m was 73%. Sure, it makes changing bands easy to keep
N6MU happy, but radiating just 18W on 40m is a major handicap. So I designed new
antennas. It starts with a 5/8” diameter x 31” mast topped with a Breedlove
elbow. The top of the 80m antenna is at 14 feet, the legal max in Oregon. The
coil Q is 620, with a 24 inch diameter top hat. EZNEC says its efficiency is
55%. It must be guyed two ways – to each doorpost – so I usually operate 80m
while parked. The 40m resonator has a similar Q, no top hat and max height of 11
feet, also about 57% efficiency. The 20m coil has a Q of 600, 96 inch stinger,
and efficiency of 69%.

Disaster: I left the 40m coil/stinger on the trunk lid at the base of the rear
window after a fast band change to 20m. I drove off and lost it somewhere in
Wheeler County. Fortunately I had packed Hamsticks for 40 and 20 in case I hit
something like the overhead limit at the Wendy’s drive through. A 40m Hamstick
mounted on a 31 inch mast works pretty well. Though I have not modeled it, its
impedance is 22Ω at resonance so it is far better than the Hustler’s 50Ω. 

But I digress. I made as many Q’s on 40 as 20m, about 332 each and 171 on 80.
The single QSO on 15m caused me to ditch the pitchfork antenna for good. Later
in the day I heard a few DX stations working the ARI test. Snagged an IT9. CE2LR
begrudgingly gave me a report. Got called by JO7WXN three times. Missed ND and
MS, AB and the rest of the rare Canadians. 836 and 55 mults for a final score of
145k. That’s 30% better than last year on basically the same route. Yes
Virginia, antennas make a difference. Next year I will add a ball mount on the
other fender so I can use the ANT 1-2 feature on the 480.

As a sponsor of the 7QP, I've got "skin in the game". I hope by giving
a good description of my gear it will encourage more mobile operations in next
year's 7QP. I'd be happy to help you.

73, Dick K4XU  ...N7XU/m


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