Stew Perry Topband Challenge
Call: K1LT
Operator(s): K1LT
Station: K1LT
Class: Single Op HP
QTH: EM89ps
Operating Time (hrs): 13
Summary:
Total: QSOs = 642 Total Score = 2,477
Club: Mad River Radio Club
Comments:
The Stew Perry Topband Distance Challenge is my favorite contest, so I
was very disappointed when the severe noise that blankets the NW from
got even stronger during the contest.
The noise is impulse noise with a much steeper rise time than I have
seen on other power line noise. The impulses have a very high
magnitude but are extremely narrow (like ignition noise), yet they are
synchronized to the 60Hz line. My noise floor is typically about -140
dBm in 250 Hz, but this noise raises the floor about 16 dB.
With the 8 element phased array, I can listen at 240 or 270 degrees
which just about perfectly nulls out the noise. The noise peaks at
about 310 degrees. So, most of the time I can use the phased array
over 3/4 of the azimuth and only hear the noise when pointing close to
due south. The noise is annoying on about half the Beverages, and
audible on most of them. The European Beverages are usually clean.
I've gone hunting for the noise in the car, but I cannot hear it in
the car. I've hunted for the noise on foot, but the only way I an
hear it is by putting an AM broadcast receiver next to any ground
connected wire or antenna. The phased array elements furthest to the
NW get a stronger dose of the noise than do the elements to the SE. I
can hear the noise, albeit less clearly on one particular power line
feeder in front of the neighbor's house. So, maybe the noise
originates in his house. He is a part-time farmer, so I need to get
permission to go poking around in his sheds to see if I can locate the
source.
For the past couple of seasons the noise has been a mostly evening
annoyance, and it usually goes away in the early morning. So the
noise would largely stay out of the way, being worst when I'm
listening for Europe.
For the Stew Perry, the noise got strong enough to begin to be
annoying even when listening to Europe. Furthermore, it stayed on
non-stop. So, after an initial burst of what sounded liked good
conditions, activity settled to a rate lower than I expected and the
extra negativity from the noise almost got me to quit.
Fortunately, I found that if I listened to the west using the 150
degree and 180 degree Beverages, I could hear most people who called
me from the west and northwest, as well as the usual plethora of
caller from Florida. In fact, using these two Beverages on the K3's
two receivers and the phased array receiver turned out to be fairly
effective for hearing most callers. Of course, I would never know
about people I couldn't hear, so if you called me and I didn't answer,
please email me! (vkean at my callsign .com) There were several
stations this weekend that I just could not hear well enough to log,
and I apologize. Conditions are not normally this poor.
The operating style is thus: I have the phased array (mono audio) in
my left ear, and the 2nd K3 receiver in my right ear. After each CQ,
I would briefly listen to the phased array while staring at the
waterfall display (which is more sensitive than my ear). Then I flip
a switch to put the K3 main receiver in my left ear (using the K3
diversity mode) and twiddle the RIT knob to find off-frequency
callers.
As European sunrise approached, the expected European rate did not
materialize, so I decided to take my 2 hour nap about 2 hours early,
and maybe work more Oceania. I took my nap 2 hours early and was
rewarded with contacts with CE1/K7CA, ZL3IX, and FO8RZ.
Both K7CA and ZL3IX popped up in my right ear while nary a peep in my
left ear until I flipped the switch. Chile is almost due south, which
is where the Beverages I was using are pointed, and the phased array
was listening due west. ZL3IX was strong enough on the 120 and 150
degree Beverages that I didn't even think to look for him on the
phased array, which was pointing 270 degrees. But there was a solid
trace on the waterfall so he should have been extremely solid at 240
degrees. After that QSO, I chose 240 degrees as the default direction
(hoping for a VK). While CQing, I kept my eye on the waterfall for a
dim trace around 1833 and after a while, I saw one. Tuning there (one
click) I found FO8RZ with no callers. I don't know why he has so much
trouble attracting attention, as his signal has been very regular for
3 contests in a row.
I found KL7RA by tuning and worked him through the awful noise. I
just had to be careful to make sure he actually responded to me. He
had a better signal to noise ratio by actually pointing a Beverage in
his direction than by listening off the side of a Beverage, as I had
been doing with other West Coast stations (signal arrival angle,
maybe?).
At dawn I didn't expect to be able to hear any JAs because of the
noise. But the noise was gone! The sun was already up but I could
hear JA3YBK. He came right back when I called, although I wasn't sure
he had responded to me. But the response was obvious when he called
again. Sorry for the delay! I wanted to be sure.
The noise didn't stay away very long. Any suggestions about how to
track it down?
So, despite the seemingly poor conditions, I was able to make all of
the normal long-haul contacts. 160 propagation remains an enigma.
DX worked: 9A, CE, DL (2), E7, EI, EW, F (5), FM, FO8, G (8), GD, GM,
I (3), JA, KH6, KL7, KP4, KV4 (2), LY (2), OE, OH (2), OK (2), ON, OZ,
P4, PA (3), S5 (3), SM (3), SV, UA, UR (4), and ZL.
Equipment: K3, ETO-91B (thanks Jeff), 65 foot "T" with 75 radials, 6
2-wire center-fed Beverages, 4 element broadside array of 2 element
end-fire arrays steerable via software radio (see Dec. 2009 QEX), and
Writelog.
Posted using 3830 Score Submittal Forms at: http://www.hornucopia.com/3830score/
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