Stew Perry Topband Challenge - Spring
Call: K1LT
Operator(s): K1LT
Station: K1LT
Class: Single Op HP
QTH: Ohio EM89ps
Operating Time (hrs): 9.5
Radios: SO2R
Summary:
Total: QSOs = 391 Total Score = 1,638
Club: Mad River Radio Club
Comments:
The fourth running of the Spring Stew Perry Topband Distance Challenge
snuck up on me. I was sure I had another week before the contest.
The plan was to finish the software for my new phased array antenna
and receiver combination enough for the system to be somehow usable.
Since I had little time, I decide to just enjoy the event rather than
frustrate myself. I'll shoot for summer for the new receiver's debut.
So I spent Saturday daytime making sure all of the short verticals
worked. I put up the first short vertical about 12 years ago, using
2x4s to support the antenna wire. Since the 2x4s would rot and break
after 2 or 3 years or the top hat wires would break of the top, I
switched to PVC electrical conduit with extra strain relief for the
top hat wires. None of those have failed. Of 16 short verticals,
only 1 wooden pole remains.
The base of each short vertical has a PVC outlet box with a resistor
to swamp the impedance, an inductor to resonate the antenna, a
capacitor to tune the resonance and an F connector to facilitate field
checking of SWR. The outlet box has a hole in the bottom which I
leave open to allow the box to breath. However, I must place
screening across the hole to keep the ants out. Aluminum screening
seems to be more resistant to the ants than plastic screening, but not
perfect. The ants prefer a dark place, so I switched to using Lexan
covers instead of PVC to let the light in. The gasket material
supplied with the PVC outlet box is useless because the ants love to
chew it up, so I use no gasket material. Thus some of the covers leak
a little. With clear covers and aluminum screening, the ants have
invaded only one box.
Between each pair of short verticals is a "marine grade" PVC box that
contains a relay and a couple of transformers. The transformers
combine the signal from the 2 verticals in an end-fire arrangement and
the relay allows switching the cardioid null one direction or the
other. A coil of RG6 provides a delay for proper phasing. Thus the
PVC box has 5 F connectors: 2 for the vertical feedlines, 2 for the
delay line, and 1 for the feedline to the shack.
I haven't been weatherproofing the coax connectors because all of my
arrays have always been in "development" mode where it has been
useful
to disconnect feedlines and delay lines for experiments. However,
water slowly seeps into the connectors and contaminates the coax. The
40 foot vertical feedlines seem to suffer from this contamination much
more than the main feedline or the delay line, perhaps because the
main feedline is buried in conduit while the short individual vertical
feedlines are just hiding under the grass. I have replaced most of
the short feedlines a couple of times because they often fail.
Finally, I noticed that the second array I built worked great for a
couple of years, then started to show the same signs of decay as did
the first array. Since there were several years between the
construction of the 2 arrays, the decay of the first array was
somewhat not apparent by lack of a comparison.
Thus while performing quarterly maintenance, I decided its time to
transition from "development" mode to "production" mode.
This means
this summer I plan to replace all of the boxes at the base of each
vertical and between each pair to make them new again. Then I will
carefully test each subsystem to verify proper functionality and then
properly seal each coax connection with self-amalgamating tape (yay for
butadiene rubber) and seal each base box cover with RTV. The final
step will be to cover each of the center switching boxes to
additionally keep water out and to keep animals from chewing on the
exposed coax.
I started the contest when I first saw signals on the band about 2
hours before sunset. Nevertheless rates were reasonable although I
wondered why there wasn't any DX because I was thinking in terms of
winter timing and not spring timing. Also the approaching noisy
weather system made the sky prematurely dark. At sunset around 2330Z,
the Europeans started calling. The sunset burst lasted about 45
minutes with 21 13 to 17 point QSOs. Also I made a lot of contacts
receiving on the 2nd radio. SO2V is much easier when using automation
to transfer the frequency from the 2nd radio to the 2nd VFO of the
first radio.
The static from the approaching weather system was quite audible even
during the daylight. When nightfall came, the static peaked early
then subsided somewhat when the rain started. Around 0220Z I had to
take some time off to try to control the wind driven rain coming in to
the house via the back door. That door has always been slightly
leaky, but not to the extent evident last night.
I got back to the radio around 0245Z. The next European didn't come
along until almost 0300Z. KH7B called at 0355Z which I suspect is the
earliest I've ever worked Hawaii on 160. After 0400Z the Europeans
were fairly steady until 0630Z when there wasn't much nighttime left
in Europe. The last G called at 0658Z.
I CQed for a few more minutes without answers so I decided to hit the
sack for 4 hours. At 1111Z I got back to the radio and parked in the
JA subband with the usual muted hope. While tuning with the second
radio I didn't hear anyone working JA, VK or ZL but I didn't listen
very long. Just after my sunrise, VK3HL called for my best DX of the
test with 32 points. I quit at 1155Z.
I didn't hear any South American stations. Sometimes that's a sign
that I am not paying enough attention to signals from the south. I
always appreciate an after the fact notification that I missed a QSO
opportunity because it inspires more effort the next time. Send me an
email if I CQed in your face: vkean@k1lt.com.
DX worked: 9A, DL (11), F (3), FM, G (4), GM, HA (2), HI (2), I, KH6,
KP2 (2), LY, OE, OH0, OK (4), OM (2), ON (2), OZ, PA, PJ2, S5, SM (2),
SP, UR (2), VK, YO, and ZF for a total of 27 entities, a lot more than
last year with a noticeably northern exposure.
Equipment: K3S/100, P3, 8410 at 750 watts, K3/100, homebrew SO2R
stuff, 2 phased array / SDR receiving systems, 12 Beverages (only 1
used), 'tee' antenna 65 feet tall over 75 radials.
Posted using 3830 Score Submittal Forms at: http://www.3830scores.com/
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