Hi Roger,
Thanks for your thoughts. Yes, the RCS-4 is the model that puts an AC
voltage on the coaxial cable and does not use another control line.
The relay box that I'm suspecting trouble with is a new one that worked fine
for several months since my tower re-build in late July, 2008. The original
unit that I had up there for a long time was Ameritron built and of course
the current one is MFJ built. It has been suggested by another member that
I may want to re-solder the relays on the board as he found some cold solder
joints on his. I will crank the tower down and have a look at that issue
after I exhaust some other suggestions today.
Thanks again for your inputs and HNY!
Regards,
Jon-K6EL
k6el@comcast.net
------------------------------
Message: 6
Date: Wed, 31 Dec 2008 17:42:58 -0500
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Subject: Re: [TowerTalk] Ameritron RCS-4 and noise?
Cc: towertalk@contesting.com
Message-ID: <495BF572.8020407@tm.net>
Content-Type: text/plain; charset=windows-1252; format=flowed
Jon Casamajor wrote:
> I have used the Ameritron RCS-4 to switch antennas on my tower for
probably
> 19-20 years with zero issues. I recently re-worked my single tower stack
and
> while we were doing that, replaced the RCS-4 switch components. My stack
is
> on QRZ so I won?t describe it here. In the past few days I have a S9+60dB
> noise level on 40m that is pretty much constant. The noise on my SteppIR,
> 20m tune, starts off about the same but settles down to maybe S2 or less,
> about what I would expect for conditions.
>
Is that the RCS4 with a control cable or the one that gets its signal
from the coax? I have two RCS-8s that are direct controlled (IE separate
wires) and I have added jumpers to short out all connectors but the
active one. I did rebuild one, but that was replace all the coax
connectors. They were in really bad shape. The threads of the PL-259s
were just about bonded to the connectors which pretty much destroyed the
RCS8 connectors when I removed the PL259s. Even if they look pretty, if
the threads are ruined they aren't much good for reuse.
I now put a thin coating of silicone on them, the mating threads, and
use flooded heat shrink tubing over the whole works. I make sure not to
get any of the silicone on the coax jacket as I want the flooded heat
shrink bonded to it.
> My 2 el 40m Yagi loads up fine and plays with a 1.1:1 SWR at the low end
> which is where it is tuned. I am suspicious that I have a problem with the
> relay box at the top of the tower that is causing the extreme noise.
(makes
> 40m completely useless) I?ve swapped out shack consoles for the RCS-4 with
a
> spare. If I leave it on the 40m position for an hour or so, it will
> eventually blow the 1A fuse in the console with the +60dB noise level.
>
Sounds like a relay is not closing which would cause excessive current.
If your's is the direct wired unit, check each lead for current. If one
relay isn't closing it will show a higher current. Often the relays have
to be adjusted when first installed.
Good Luck,
Roger (K8RI)
> I feed the tower with a buried ?? hard line to the tower and low loss
LMR400
> up to the switch. I also have VHF and UHF Yagi?s on the stack that are fed
> with separate hard lines and nothing has changed with those feeds.
>
> If anyone has any ideas I would sure appreciate the input. I am
suspicious
> that the relay may be hanging up and putting the AC switching voltage back
> onto the feed line somehow.
>
> I?ve had Pacific Gas and Electric, our power provider, out here and he
took
> a ?picture? of the noise and agreed it was horrible. They are still
looking
> for problems and have found a very noisy pole maybe a mile away. They have
> been great with their response and support in looking for the problem. I?m
> out of ideas! :-(
>
>
>
> Regards,
>
> Jon-K6EL
>
> k6el@comcast.net
>
>
>
> _______________________________________________
>
>
>
> _______________________________________________
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