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[VHFcontesting] ARRL Jan VHF N8RA Single Op LP

To: "YCCC reflector" <yccc@yccc.org>, <vhfcontesting@contesting.com>
Subject: [VHFcontesting] ARRL Jan VHF N8RA Single Op LP
From: "Chet S" <chetsubaccount@snet.net>
Date: Mon, 25 Jan 2010 11:27:37 -0500
List-post: <vhfcontesting@contesting.com">mailto:vhfcontesting@contesting.com>
Call: N8RA
Class: Single Op LP
QTH: FN31 in CT
Operating Time (hrs): 18

Band  QSOs  Mults
-------------------
    6:   135    23
    2:   138    26
  432:   36    11
-------------------
Total:  309    60  
Total Score = 20,700

Club: Yankee Clipper Contest Club

During the weeks leading up to the contest, I did not feel the station would
be ready- there were a number of  antenna problems to be solved, and my time
was limited, plus I did not feel inclined to climb the tower during very
cold and windy days. During one break in the weather, the problem of
antennas pointing in a direction opposite the rotor indicator was traced to
a loose rotor clamp around its rubber shock damper, and that was easily
fixed But the big mystery was why had the SWR on a 6M antenna changed? It
had been 1.6 to 1 but was now 1:1. Relay DC switching paths and coax
continuity looked normal from the shack. It also seemed that the Philly
beacon was not coming it too well. Something seemed wrong...was 6M going to
be NG for the contest? 

A number of line noises had appeared in new directions around the
neighborhood, affecting both 6 and 2M. The noise blankers, which in the past
had been pretty good with them, now had little effect. What is that about?

Earlier in the week I changed out the remote mounted Demi 2M preamp for a
Ramsey one. Though the Demi unit promised a lower noise figure, it was prone
to spurious oscillation and also overload by the 6M signal. The Ramsey unit
offered a 3 section tuned input section and helical output filter and did
eliminate the overload problem, allowing me to listen on 2M while CQing on
6. 

Friday night, I discovered to my panic that the Orion would not transmit! A
frantic search thru the connections with the sequencer did not show anything
amiss. Dropping back to a simple configuration showed that the problem must
lie within the radio. When was the last time it worked OK? Aha, I had
reloaded a previous version of firmware a few weeks ago but had a hiccup
during that load. So I did a master reset and reloaded the firmware again,
and voila, the transmitter section came back to life. 

After a late night, Saturday morning came too early, and I was still not
ready. I found again that some of the antennas were not pointing in the
indicated direction. Another trip up the tower revealed that rotor clamp was
again too loose. This time I removed the rubber damper sheet between the
clamp and the chain drive shaft. The damper was a good idea for shock
absorption but was not holding tight enough to the shaft during cold
weather.  

The 6M SWR had changed back to its normal 1.6. Outside temps were above
freezing now. I wonder if there had been ice on the driven element. 

Started the contest on 2M. Signals seemed weak and it was difficult to be
heard. My CQing was not producing any answers. After a couple of hours of
this, a local stopped by the freq to tell me that my audio was not real
clean. That was odd since it seemed good in the monitor, but did have a
slight rasp. SWR on 2M was abnormal too. To make a long story short, I think
the problem was due to a recently introducing extra line length in my 50 ohm
shack cabling to the 75 ohm CATV feedline. This caused the SWR at the
amplifier to be such that it may have been badly mis-tuned or unstable. Even
the transverter barefoot did not like the load. By adding a few more feet of
50 ohm coax, the amp and indicated SWR settled down and I got a clean bill
of health from the local, and now I was making contacts again. A lesson here
is to locate the SWR meter right at the output of the amp, rather than at an
intermediate connection point so to have a better idea of what impedance is
presented to it. 

The strange line noises were still there making weak signal copying
difficult. Band conditions seemed quite poor, and at this point, I had the
feeling that the contest had passed me by. Well it was a learning experience
anyway. But by evening, things were looking up. The log was growing.
Interestingly, the more I operated, the quieter the line noises became. By
late evening, the noises were back to "normal". Were these new sources kiddy
toys or touch lamps that were now going berserk from my RF, so their owner's
pulled the plug? I can only hope. 

So there were low points. But there were plenty of high points too, and
that's what keeps bringing us back. 

-2M: if you like digging for weak signals, and I do, this was a good weekend
for it. It was exciting to work a couple of VE2's on 2M, and also down to
FM07 and FM16 (400 miles) from here. This is part chance, if you are
listening at the right part of the band and pointed the right way, you can
sometimes luck out. Those last two grids I only heard once and only for a
couple of minutes. Overall, activity on 2 seemed to be down, perhaps due to
poor conditions, or maybe I missed a lot of casual ops during the opening
hours when I was having problems.

-6M: Here I struggled to be heard on Saturday but seemed to have an easier
time on Sunday, yet signal strengths did not seem much different. Maybe when
all the strong signals are logged, us low power guys can get through better.
A nice surprise was working a few stations on WSJT meteor scatter during the
wee hours. I've gone through contests with nothing worked or even heard on
this mode but managed a few contacts this year.

-70cm: Now that my sequencer design had settled out, I had neatened this all
up and put it all in one chassis. That worked well as did the antenna put up
earlier this year. It is a PITA though to have the 70cm antenna pointing 180
deg from the 2M one, requiring turning the antennas when moving someone from
2 to 70. Yes it is on the list for summer.

- chatting with the locals: always nice during a contest like this. 

It is becoming obvious that the shack needs to be stripped down to a bare
operating table again and the equipment rearranged and reinstalled, paying
attention to bonding, separation and routing of cables, and ease of
reconfiguration for HF vs VHF vs multioperator use. The addition and removal
of equipment and accessories in the last few years has made it a bit of a
mess. Sounds like a good winter time project if I can find the time. 

Thanks for all the Q's. 

Chet, N8RA, FN31 in NW Connecticut

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