Hi Ignacy,
Thank you for your reply. I use gloves for most significant physical
tasks to protect my hands. The strange part is that unlike almost every
other splinter that I have ever gotten, I did not feel this at the time
and can't even imagine what I did to get it. It was in the morning and
I was not doing anything in my house that would have been a risk to my
fingers. The cause will remain a mystery.
I know that DX Engineering also has a 4-square but I am not familiar
with what is different about it or why you feel it is superior to the
Comtek. If I were to get it, would the cabling or the length of the
coax phasing lines be any different? I would appreciate any specifics
that you can provide.
Tnx & 73
Bob, KQ2M
On 2022-07-14 06:42, Ignacy Misztal wrote:
Bob,
Terrible problem with the splinter. We nearly always to remember to do
certain tasks with gloves, but sometimes we forget.
If money is available, the dxengineering 4sq is way above that of
Comtek. If you can reuse the controller, the switching unit is almost
half price of the complete package.
Ignacy NO9E
On Thu, Jul 14, 2022, 00:29 <kq2m@kq2m.com> wrote:
My apologies to all for the extreme delay in responding. I got a
long
wood splinter under my pointer finger nail and it got infected and
ballooned rapidly necessitating a visit to my internist and then to
a
hand surgeon who had to cut open the nail and remove some skin and
the
splinter. Unfortunately he had to cut it open again 10 days later.
As
you can imagine it was a mess, extremely painful and almost
impossible
to type with the multiple layers of bandages. 5 trips to the hand
surgeon and 3 weeks later it is finally mostly healed.
Many thanks to NO9E, NA6O, W5JMW, W4EF and N3AC for their thoughtful
and
very helpful responses.
I had checked the coax, control cables, dummy load, Wire elements
and
feedlines just to be thorough and everything looked fine. And then
I
opened the ACB-80 relay box and spotted a fully charred relay and
partly
blackened circuit board and then noticed that the other two relays
next
to it either had significant corrosion or lichen growth inside, or
both.
Whatever was on the relays likely caused the relay immolation but
it
was surprising to see given that the relay unit was held in place
with
antenna ports facing down and then that was placed under a large
heavy
duty plastic bin to prevent water, leaves, etc. from getting inside.
I am sending the relay unit back to DX Engineering for service along
with the control box. My understanding is that there is currently a
6 -
8 week backlog for repairs. The unit is 27 years old. It would be
great to be able to get another 10 - 15 years out of it. I won't
need
it after that.
73 and thanks for all of your help and information!
Bob, KQ2M
On 2022-06-27 14:17, Ignacy Misztal wrote:
If a mismatch in the 4 SQ should cause high dumped power but
little
SWR change, it suggests that the Comtek box has a problem.
Perhaps during testing with the elements out of order something
has
fried.
Comtek has a reputation of less reliable relays. My 2 year old
Comtek
stack match stopped switching and a KW sent to the stack fixed the
issue.
Ignacy NO9E
On Sun, Jun 26, 2022, 19:23 <kq2m@kq2m.com> wrote:
Hi,
Before WPXCW one month ago, my wire 80M 4-square using the COMTEK
ACB-80
was working very well, with ~ 1500 W out and 100 w reflected at
3.5
mhz
and ~ 1500 W out and 50 w reflected at 3.7 mhz. The F/S and F/B
wer
excellent and about as predicted when the DX station signals were
low
angle.
Between then and now (one month) we had two violent windstorms
and a
few
nasty T-storms, with gusts approaching 50 - 60 mph but tame
compared
to
what it has been through in the past. 2 wire elements broke off,
the
F/B and F/S disappeared and the forward power dropped to ~ 800 w
with
350 w reflected from from 3.5 - 3.7 mhz. That's normal and to be
expected.
However, when I fixed the two elements today, while the F/B and
F/S
improved somewhat, the forward/reflected power did not go back to
the
usual values. That is NOT normal.
I checked each of the connectors and continuity at the bottom of
each
element and everything appeared to be fine. I checked all the
phasing
lines and they appeared normal. All the elevated radials were in
the
air at their normal elevations. I could not find anything wrong.
There
was one sketchy looking connection on the feedline to the shack
and
I
made a new connection with a new Amphenol pL259, but there was -
still ~
800 w forward 350 w reflected from 3.5 to 3.7 mhz.
I seem to remember something like this happening about 10 years
ago
with
high reflected power and loss of F/B and F/S as a result of
multiple
COMTEK external relay box cold solder joints that were not
obvious.
DX
Engineering checked it out found the cold solder joints (that
COMTEK
did
NOT find) and fixed them and priority shipped it back to me so
that
I
would get it before CQWWCW which I did! But the F/B and F/S was
worse
then than it is now so I am not sure that it is the same thing.
What is striking to me is that the forward power has uniformly
dropped
and the reflected power has uniformly risen across the entire
band
as
though the entire array was detuned by 500 khz, suggesting
something
systemic. I suspect that the problem is in the relay box but I
can't
figure out what may be causing this.
Has anyone experienced a similar problem with their ACB-40,
ACB-80
or
ACB-160? Does anyone have any idea of what to do look for next?
Tnx & 73
Bob, KQ2M
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