ARRL 160-Meter Contest
Call: K1LT
Operator(s): K1LT
Station: K1LT
Class: Single Op HP
QTH: Ohio EM89ps
Operating Time (hrs): 31
Summary:
Total: QSOs = 1495 Sections = 82 Countries = 32 Total Score = 380,874
Club: Mad River Radio Club
Comments:
Death by a 1000 Paper Cuts
Well, not really death but perhaps a sub-optimal performance and no
paper cuts, but a slew of issues.
This past summer I built another broadside / end-fire phased array
because the first one works so well. The first array switches between
NE and SW which covers most receiving chores. The new array covers NW
/ SE, primarily to handle W7, KL7, and JA which have always been
problematic from here. Either array can have multiple, simultaneous
beams.
I had the new array ready by the Stew Perry Warmup, and it works,
although I did not have it properly integrated with my station at that
time. The challenge was to allow both arrays to feed my limited set
of ears in any reasonable combination without a lot of switching
effort. The current software uses all of the numeric keypad buttons
to select from 16 pre-programmed directions. The desired improvement
was to have the optimal phased array selected by direction, and allow
2 choices of direction to be arbitrarily selected, one for each ear.
The solution is just a simple matter of software to be added to the
existing system.
Just before the contest I finished implementing the audio routing and
direction setting software changes. However, in my haste to perform
this chore at the last minute, I made a significant mistake which
caused the I and Q audio channels (parts of the digitized audio
stream) for the right ear to be crossed with the I and Q channels for
the left ear. Since the streams are phase locked, this problem didn't
show up when I tested on an empty band but did show up for real
signals when switching to any direction other than the default (Europe
and US East Coast). Since I didn't understand my error yet, I was
studying my software changes while operating the contest. Eventually
I realized my mistake and began correcting my error, while operating.
During this period I used the beverages to receive in directions other
than NE.
Meanwhile, about 2 hours into the contest, K5RX transmits on my
frequency "clixs, pse qsy up". This was a very disturbing message.
A
few years ago K5RX emailed me that I had bad key clicks which prompted
my decision to retire the IC-765 and buy the K3. (The key clicks are
"designed in" to the 765 and would have been very difficult to fix
without major changes). While operating, I assembled a temporary
antenna for the KX3 and listened to my signal. Since a clip lead is a
very short, high impedance antenna, there was lots of hand capacitance
effects and perhaps RF was coupled into the KX3 via the tuning knob.
My signal didn't sound perfect, with hum and some clicks, although the
hand capacitance effect made me unsure. I unplugged everything
non-essential from the K3 and turned off the AC supply to allow the
battery to carry the radio. The hum and clicks remained. So I
decided to swap out the ETO 91B for the Alpha 8410 and put up with the
noisy fan.
I cleared off the space around the amplifier and cleared a path so I
can carry heavy objects. I unplugged the keying line and operated low
power for a few minutes. I paused the CQ machine, unscrewed the rig
to amp jumper cable and moved the antenna cable to the radio and
resumed the CQ machine. I swapped amplifiers and hooked up the keying
cable. To preparation to swap the new amplifier into the line, I
unscrewed the PL259 shells and held them against the sockets. Then I
pressed ESC to stop the CQing machine to swap the cables. Just as I
pulled the coax from the radio, someone goes "??" on my silent run
frequency. Gack! What timing! I decided to continue the cable swap
rather than try to defend the frequency. So while I'm tightening the
shells on the PL259s, K5RX starts CQing on my former run frequency.
Sounds like a devious plot except that there is no way anyone could
expect to acquire a run frequency by telling someone that they have
key clicks and starting a chain of events.
I found a new frequency and resumed running, but my signal on the KX3
sounded unchanged. So, apparently, the amplifier isn't causing hum
or maybe key clicks. I noted via the band scope that other people
were not avoiding the frequencies adjacent to me. I connected my
oscilloscope to a spare beverage feed and observed that my waveform
looked reasonable. I texted K8ND (who was not on Curacao) and asked
him to listen to my signal. He replied that he heard no clicks. I
emailed my contest club to solicit observations. I received 3 emails
of "clean signal". While executing these steps, two more people
complained of clicks on the air. Do I have key clicks? Should I
suspend my operation to investigate?
To make a long story shorter: I had to stop briefly twice more to
correct errors in my software for audio routing. By Saturday night,
though I had it working properly which allowed me to receive from east
and west simultaneously and switch directions at the touch of a
button, without (hardly) any dead spots. (Due north and due south are
still weak directions.)
Conditions were better the first night although the Europe sunrise
enhancement was more prominent the second night. Noise was low, and
my neighbor only forgot once to not turn on his track lights. The
track lights noise caused a 20 minute "outage" Saturday night around
0237Z. Around 0500Z some broadband impulse noise that did not sound
like line noise began to raise the noise floor by ultimately 6 db, but
by the time the noise reached the worst level, most of the action had
shifted west.
Saturday night the band got very full. It looked almost like the CQ
160 on the band scope. I found myself calling CQ on 1832 at one
point, but then I felt guilty. I checked the rules and they still say
"1830-1835 *should* (not *must*) be used for intercontinental QSOs
only". So I abandoned 1832 without receiving any replies. My
apologies for not causing any QRM. No apologies for squeezing in
somewhere else.
HK1MW was the surprise multiplier. Worked all states by 0549Z, all
but PR and NT by 0709Z (NNY was the last "easy" section). NP4A
called
Saturday night and never I heard or expected NT. Did not hear any
evidence of VK and ZL. Heard a couple of 5's running JAs.
DX worked: 9A, C6, CE, CT (2), DL (20), EA, F (9), FM, G, GM, GW (2),
HA (2), HK, I (9), LY (3), OE, OH (2), OK2, OM (5), ON (3), OZ, PA
(2), PJ2, S5 (3), SM (5), SP (7), T32, UA, UR (7), V3, VP5, and XE
(2).
Equipment: K3, P3, 8 element and 6 element SDR receiving system (still
need a name for this concept), ETO 91B (thanks K8ND) and Alpha 8410
with added noisy fan to override the sporadic noisy fan, 6 2-wire
Beverages for coverage every 30 degrees, 65 foot Tee antenna with 75
125 foot radials under the grass.
Posted using 3830 Score Submittal Forms at: http://www.3830scores.com/
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