Hi VHFers,
I should have changed the name of the 222 MHz Sprint up here to the "222
MHz Stagger", because that's what I was doing all night. I had serious
equipment issues that started up just about 23:45 UT. I have had this
problem before and I was sure that I had fixed it. Right in the middle
of the Sprint, all of a sudden, my K3 would stay in transmit and that
made receiving impossible. I did all the typical things to see if I had
a bad cable somewhere, but everything checked out except the 12
conductor cable that goes from the K3 to my homebrew band decoder box.
The cable has band decoding lines along with other handy accessory
features from the K3 that can be utilized on a per band basis. Last
Fall, I had the same problem and took the whole system down to the house
and found a broken wire inside the multi pin DB-15 connector. It was
free to move inside the connector shell and was causing problems. I
thought I had fixed it as it has given me no trouble all winter....until
last night at 23:45 UT. I ripped things apart in an effort to fix it and
keep going in the Sprint, but the problem got worse, and it defied
explanation. It appeared that the cable itself was at fault, but a
physical check showed all the pins were properly connected on either
end. I bagged the Sprint and took the K3 and the band decoder out of the
shack and brought it down to my workshop. When I connected it all up, I
saw the same problem. A closer look and I could see 3.5 to 5.5 megohm
paths between all the pins in the connector. The value drifted around
and I suspected that the leakage in the cable might be fooling the K3
into going into transmit. A check with a bath of alcohol and heat gun
isolated the problem to one end of the cable at a DB15 connector. A bit
of hot air made the resistance drop quite a bit. (?) The next morning, I
was at it again and unsoldered the 15 pin connector. A quick check with
a DVM showed the cable and other connector were fine, but the DB15 was
suffering from some weird internal leakage paths all by itself! No
amount of cleaning could alter that fact. A simple resistance check of
all the wires looks fine with good connections thru the cable and no
direct shorts are seen anywhere. The leakage was the only problem I
could see.
The weird thing is that a quick check of the K3 keying showed that a 10K
resistor to ground on the key line would key the radio, but a 33K
resistor would not key it. I was seeing resistance leakage values of
maybe 500K at the worst. I am not sure that the leakage caused the
failure. Maybe it had to do with something I am not aware of, but I just
know that the DB15 should *_not_* show leakage. Remember that this setup
is in a cold and damp shack and the gear does take a beating as a
result. Maybe evil mice are involved? Have I mentioned that mice do
not deserve to live on this planet?
As far as my effort in the 222 MHz Sprint goes, I was on for almost an
hour and about another one half hour after that trying to fix things.
Making contacts with the fault was almost impossible. I worked 27
stations, and found QSB to be severe. I listened to VE3DS work K1TEO,
and called right after Dana worked Jeff. He was about S2, but peaked up
at 579 when he turned his beam towards me. Of course the rig quit and I
could not hear his answer, so I tried again later when the errant keying
had quit acting up, and then VE3DS was just a whisper in the noise. He
was barely copyable. N2JQR in WNY was pretty loud when I worked him,
and W8ZN at 482 miles was easy copy from FM09te. We had a bit of
trouble with the QSO as there was line noise on the VA end, so we had to
repeat things for awhile. I heard AA2SD OK on SSB from his FM29 location
early on, but too much QRM & splatter prevented me from trying with him.
222.102 was a busy spot! I was not on long enough to really get a good
idea of conditions. I suspect that they were down a bit. WA1RKS and
W1AUV were easy contacts this time. Due to the rig problems I missed a
whole bunch of the regulars. Not sure how many grids I ended up with in
the first hour. When I check the log, I'll post it on 3830.
I was really bummed at the rig failure, as I had expended much effort to
get the array put back in shape after the big ice storm. WA1T and his
son Nick dropped by to help with the tower work. I had climbed the tower
in the morning and rigged up a rope and pulley system. I also managed to
straighten a few elements with an aluminum tweaking arm. When the
helpers showed up, Nick and I were up on the tower and managed to slide
the big H frame sideways to get access to the antenna with a broken boom
truss. We got that repaired and sraightened a few more elements. It was
quite windy and of course it was raining only when we were on the
tower!! We quit at about 4:30PM on Monday and I see on;y two badly bent
elements left, so I was hoping to give the antenna a good workout on
Tuesday. Unfortunately, that did not happen.
So now I am testing my band decoder with a new DB15 plug and hope that I
made some progress.
73
Dave K1WHS
On 4/17/2024 10:14 AM, Ron Klimas WZ1V wrote:
222 MHz Spring Sprint 2024
Call: WZ1V
Operator(s): WZ1V
Station: WZ1V
Class: Single Op HP
QTH: FN31RH
Operating Time (hrs): 3.5
Total: QSOs 44 Mults 19 Total Score 836
Club: North East Weak Signal Group
Comments:
Good activity on 222, although several regulars were MIA.
Missed a few easy grids as a result. Conditions mostly average,
except signals from the north east seemed to be depressed.
Nice to work several WNY and VE's. No new Q's after 10 PM.
Hope to work some of you again next week on 432.
73 Ron WZ1V
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