[Antennaware] Question

K9AY k9ay at k9ay.com
Fri Oct 31 14:06:39 EST 2003

I also have had problems over the long term with "sealed" connectors. Back
when I was in broadcasting, I was always getting water in supposedly
weatherproof N connectors, even when sealed with rubber tape or RTV type
sealant.  This would develop over a couple years' time, so I suspect it is a
problem with temperature swing.

Now, I do not seal my connectors, hoping that they will dry out easier in
warm or dry weather.  I try to install them with protection from direct
exposure to rain, usually with loops that can be covered with a hood (like
an upside-down bucket). Other ideas are welcome.

I will be starting on a new antenna farm next year, so this is subject of
great interest.  I have obtained a number of surplus DIN 7-16 connectors,
and hope that their design will allow them to stay sealed over time.

FYI, this was not an issue when I lived in Coloado! But it was a big deal in
Georgia where there was plenty of rain, fog, dew etc. I never saw bare steel
rust as fast as it did down there. Now I'm in Wisconsin, where temperature
change is more of an issue.

73, Gary

PS -- This is probably more appropriate for Tower Talk but I'm glad to see
the traffic on this reflector, and the 'noise level' on TT is awfully high.

> Mike etal,
> Sealing an RF coax connector is a constant problem. When I moved to New
> England (from San Jose) in 1974, everyone up here said "get some silicon
> grease (I think they called it DC-4?) and squeeze it into the connector to
> keep out water and then seal the connector with electrical tape.
> I did what they recommended but a few years later I started to have
> problems. It turned out that small droplets of water did somehow got in
> migrated into the silicon grease. Eventually it caused an RF path and I
> flash overs that blew up the connectors on VHF with moderate power (500
> What I found out is that (what I think) is the proper technique is to not
> apply the grease inside the connector but instead lightly apply a thin
> layer of silicon grease (the compound you find in a small packet as you
> described) sometimes enclosed with expensive connectors or antennas to the
> connector threads and then apply tape on the outside of the connector to
> seal it. If all goes well, and water intrudes, the grease will usually
> confine it to the threads. A small amount of water inside the connector
> usually doesn't hurt.
> 73,
> Joe W1JR
> At 04:02 PM 10/15/2003, Mike Switzer wrote:
> >I am getting ready to put up my new tower and antennas (been 20 years
> >I have had a real antenna).  I have used in the past a "filler" to keep
> >moisture out of my connectors.  I forget what I used can anyone let me
> >what is advisable.  By the way I have used this on some and not used it
> >others and never noticed any difference.  I worked for Motorola years ago
> >and with every installation we got a little packet of "grease" to put in
> >connector.  I don't remember who the manufacturer was.
> >
> >
> >
> >mike
> >
> >
> >
> >K8ZE
> >
> >k8ze at charter.net

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