[VHFcontesting] W1RT/r UHF post-mortem

John D'Ausilio jdausilio at gmail.com
Mon Aug 6 07:52:34 PDT 2012


I guess I should have learned from last time ... no matter how much
time allocate, it will take at least 10% longer than that to complete
any given project ;)

Last year I decided that it was time for a change in Jitney design ..
I wanted to increase the depth of the operating bench to allow a K3 to
fit comfortably, and I wanted to move the battery box from just behind
the front seats to the center of the operating bench opposite the
rack. I started the project in late May since I knew I was not going
to be operating in June, and Xtof made plans to come out for the UHF
'test since he was going to need to be in Belgium for the September
'test. The inside work went pretty smoothly, but the integration took
quite a while as many things changed location. Ultimately we were
still working on the thing Friday evening at 11PM ...

Saturday morning I decided things appeared to be working well enough
to head towards Camelback. We got on the road around 10AM, dodged a
bullet by detouring to the Tappan Zee (Cross Bronx was a disaster with
construction and accidents), but then about 10 miles shy of the PA
state line I80 came to a dead stop in all lanes. My Iphone traffic app
showed that the road was entirely closed right at the state line. We
maneuvered out to the left lane and took a handy dirt path across the
median to the eastbound side .. not recommended but in the heat of the
moment it seemed like a good idea ;) This got us onto local roads, and
we were able to skirt the problem area entirely and come up to
camelback from the south on US33 .. arriving only one hour behind
schedule.

Once we got cranked up and started making contacts it was evident that
the jitney was not ready for operating ..
- low band station was experiencing the Elecraft ALC problem (junk
getting into TX port and shutting down power)
- 903 RX no TX (fixed on site before leaving)
- 3G TX no RX
- 10G all around weak
- logging computer lost it's mind, so no logging, beam heading calc, etc

Then the storms started popping up .. they mostly went around the
mountain but I was nervous enough that we cranked down for a while and
drove down to Cameltop and hung out there for an hour or so until
things cleared up a bit. Sundown arrived and we headed back home
(skipping the planned alamuchy stop due to grumpiness from all the
problems).

Sunday morning we took a look at some of the issues with a clear head
and decided we'd be better off hanging out at home and fixing stuff
than heading to Mohawk. 903 we fixed up there (disconnected RF input
to amp), 3G turned out to be a bad cable inside the microwave box
(between transverter and barrel on back of box), 10G is still a bit of
a mystery but Xtof thinks it may be the input fet is blown. Low bands
just need new cabling and maybe a low-pass filter in the TX line ..
and ultimately I need to set up my own switching and abandon the
Elecraft common IF system in favor of regular relays. Computer is
still giving me problems .. we've been using a multiseat solution from
userful.com with ubuntu to enable a single computer to serve as
logging for both seats, and it somehow got messed up .. then I
realized that they had pulled the old versions of the tool from the
Ubuntu repositories so we couldn't get it going again. I'm having to
do a manual multiseat setup, which should be done for Sept ..

Anyway, we got a bunch debugged and should be in much better shape for
Sept VHF .. I don't have much in the way of logging from this past
weekend, I lost the microwave log entirely though I have Xtof's paper
log from 222/432, so no log will be submitted ..

de w1rt/john


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