I've said it many times, I used to feel like you toward connectors,
until a direct lightning strike to the top of my tower removed all of
the weatherproofing and 15 minutes later I had water running out of my
rig onto the desk top. It didn't hurt the rig, but it ruined the desk
top. 40 years total at 3 locations with nary a problem, but one strike
ruined 200 feet of 9913, IIRC 8 connectors, and a desk top
If you are on HF, Unless it is a long line, or you consider the legal
limit as QRP, as far as I can see, there is little to be gained from
using these expensive cables
I found 1/2" Heliax too fragile for kinking, or being stepped on. I gave
away two 100' runs with connectors. and went to LMR600. Now if I could
have found 7/8ths Heliax at a reasonable price, I would have used it for
VHF and UHF. The only time I saw a good price was a pick up load for
the repeater that was free free, but none as an individual.
Total length from my rigs to the top of the tower was 200 feet with
rotator loops and 28' pigtails to the antennas
73
Roger (K8RI)
On 9/7/2016 Wednesday 7:50 PM, Kevin wrote:
I believe it all started with the superiority of heliax/hard-line from
a loss perspective and since UHF type connectors for such cable are
expensive and rare why not use 7/16 DIN, a commercial standard connector.
On 9/7/2016 10:26 AM, StellarCAT wrote:
Forgive me - I've replied to Gerald's email but this is directed to
the thread in general: WHY all the concern for sealed connectors and
connector types? I've been using UHF for 49 years and the only time
I've had issues with those installed outside it was my fault - either
poor wrap of tape or poor solder job ... I've had cables with
connectors that were out for years with electrical tape wrapped
around them in 2 directions - years later when disassembling them for
a move they were utterly pristine! I don't get it - why so much
discussion?
Gary
K9RX
-----Original Message----- From: TexasRF@aol.com
Sent: Wednesday, September 7, 2016 8:56 AM
To: john@kk9a.com ; towertalk@contesting.com
Subject: Re: [TowerTalk] LMR600 male DIN
John, you bring up a valid concern. I am not aware of any coaxial type
connector that could be considered waterproof. The fundamental reason is
because the threaded connections do not create a hermetic seal when
they are
screwed together.
There are inevitable air spaces inside the connectors and coaxial
cables.
These air spaces will fill with air. When the air is heated (like
outside
in full sun) it will expand, creating a positive pressure.
Conversely, when
the air cools (like at night), it will create a negative pressure. This
negative pressure will suck tiny amounts of water vapor through the
threads of
the connector.
If enough water vapor is present droplets of water can condense
during the
cooling cycle and over the course of days and weeks can collect
inside the
connector. Once inside, there is no escape and the droplets continue to
collect over time.
If there are rain or dew drops of water on the outside of the cable,
they
can also leak through the threads and collect inside the connector.
Gravity
is not your friend here.
Many commercial applications pressurize all of the cables even if
they are
foam filled types to prevent the problem. You may have noticed many
of the
Heliax type connectors have air fittings; that is why.
73,
Gerald K5GW
Over
In a message dated 9/7/2016 5:37:52 A.M. Central Daylight Time,
john@kk9a.com writes:
Is any TX connector really water proof? Are DIN's being professionally
installed with no external butyl rubber and tape? On the two outdoor
DINs
that I have, I weather proofed the connection the same way I did with
UHF
and N connectors.
John KK9A
To: towertalk@contesting.com
Subject: Re: [TowerTalk] LMR600 male DIN
From: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>
Date: Wed, 7 Sep 2016 01:08:48 -0400
Take care!
According to the Amphenol page N-Type are not water proof/weather
proof.
73
Roger (K8RI)
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73
Roger (K8RI)
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