The installation video agrees with you.
PL259s: The problem with solder type PL259s is usually not the braid
that so many complain about, but rather the center pin. Most apply heat
to the pin. This often results in solder getting on the outside of the
center pin. There is little room in the female SO239 for the now
oversize center pin. This causes the expansion of the receptacle to the
point where future PL259s with no excess solder do not make a good
connection. Extend the center conductor through the center pin far
enough that the heat can be applied to it and the tip of the center pin
of the PL259. The copper center conductor will carry the heat and thus
the solder down into that center pin of the PL259. Solder will
generally tend to flow toward the heat source. Heating the center pin
usually does not heat the center conductor until the solder connects
both. So heating the copper wire and the tip of the center pin "usually"
causes the solder to flow to where you want it.
This mismatch can be difficult for the average ham to find as the
connection may be intermittent and is often not visually evident leading
to trouble shooting the antenna and or tuner.
The ARRL Hand Book has a pictorial of how to properly install PL259s,
but there seem to be lots of variations out in the wild. If the braid
isn't installed as per the directions, it can create a much larger
impedance bump if installed on the outside of the PL259. You now have
the entire length of threaded portion serving as an over size shield
rather than the short gap between the end of the braid and the shell.
making the area that is no longer 50 ohms many times that of a properly
assembled PL259. It's handy on FD, or a temporary installation to just
screw the connector over the braid rather than solder the braid in the
connector basically creating a permanent connection. This "usually"
works, but I've lost count of how many I've found in permanent
installations, usually when there's a foot of snow on the ground.
I know that many of us need to save our pennies, but saving a few cents
on a connector, while ruining many feet of coax is costing rather than
saving. "Most" coax runs only have a couple of connectors, so they are
by far the cheapest part of the installation. Here, using "good"
connectors and taking the time "Properly" installed them will likely
give better performance while saving money in the long run..
As many have said, the loss from the connectors does add up. Properly
installed PL259s, crude as they are have very little loss. One
improperly installed connector can have the loss and impedance bump
equivalent to quite a few properly installed connectors. Add to that
what damage they may cause to the coax over time along with degraded
performance. The SWR improving with time is not a good indication of
things getting better with age!
Today's top end coax cables often have a foil shield with fine Al wire
for a braid. Water can cause that foil and braid to completely
disintegrate in just a few months or less. True, much of that was done
to save money, but the foil gives good coverage and the coax is lighter
than one made using copper.
There is the approach touted by many, including me at one time, that
water will be no problem if you properly weatherproof the connections.
It only takes one lightning strike to remove the best of weatherproofing.
One strike to the top of my 100' 45G removed all of the weatherproofing
and silver plating from the connectors "up there" and within 15 minutes
My 200' 9913 hose had water running out of my rig onto the desk top.
73
Roger (K8RI)
On 9/6/2016 Tuesday 9:51 AM, Kelly Taylor wrote:
Far be it for me to argue with someone in the industry, but…
The DIN install videos I’ve seen suggest the centre conductor is soldered into a
shallow well inside the connector, almost the way a conductor would be soldered to the well
inside a chassis-mount SO-239. Considering the centre conductor of a PL-259 passes through to
the end of the connector and is soldered there, with perhaps a greater degree of
conductor-solder-connector contact to grip the conductor, and given the crimp-and-solder
style PL-259s employ a similar clamping scheme to DINs, I’m just curious about the
statement regarding mechanical superiority.
It seems the centre conductor might be the weak link. Can you clarify, Steve?
As for the crimp-crimp style PL-259s, is there a valid reason the instrux
typically warn against soldering the centre conductor?
73, kelly, ve4xt,
On Sep 4, 2016, at 10:33 AM, Steve Maki <lists@oakcom.org> wrote:
On 9/2/2016 0:33 AM, Jim Brown wrote:
I've been gradually converting to all DINs everywhere that it's
reasonabl
Why? Are all your systems at UHF?
No. In my business we use nothing but 7-16 DIN nowadays and it does not take
long working with them (like 5 minutes) to realize how superior they are, even
if just mechanically (at HF). And of course I have a good supply on hand, being
in the biz.
So when I ran all new hardline out to the towers a few years ago, it was an
easy decision to switch to DINs on the main lines and on jumpers - at each end
of the hardlines - to the point where I encounter a device with a UHF connector
that is inconvenient to replace, like a wattmeter, balun, etc.
-Steve K8LX
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73
Roger (K8RI)
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