[TowerTalk] Hardware Question

[Mahlon Haunschild]

Jack, a proper electrical connection requires metal-to-metal contact of 
sufficient pressure to keep oxygen out of the connection, thereby 
preventing oxide formation, which would increase the resistance of the 
connection relatively quickly.  Soldering gets around the pressure 
requirement because the wetting action of the soldering process prevents 
oxygen entry at the contact point (assuming, of course, that the 
connection was soldered properly).  If you just screw the shell onto the 
cable, you don't have good high-pressure contact between the braid and 
the shell, which will eventually lead to failure.  It may work for a 
little while, but eventually it will fail.  Incidentally, the PL-259 was 
never designed to be installed this way.

By contast, consider the design of a type N or BNC conntector: a 
high-pressure cable clamp exerting its force on a relatively small area 
of the cable braid (the part that's fanned out over the lip on the front 
of the clamp ring).  No chance of oxides forming there.  There's no way 
that a "dry" PL-259 can perform as well as this over time.

On the subject of soldering "weapons" for PL-259s:  Master Torch and 
Weller used to sell a rather large butane torch/iron (not to be confused 
with the "PortaSol" brand products).  I used one of these years ago for 
soldering PL-259s, equipped with the biggest soldering tip available. 
Worked GREAT until the catalyst in the tip burned out...

regards,

Mahlon - K4OQ

Jack Berry wrote:

> I have used a combination approach. A 100 what gun
> with the PL-259 resting on the hot gun tip and a
> Weller butane at the hole for localized heat.
> 
> Going the other direction - What are the potential
> consequences of NOT soldering the connector to the
> shield? I have two non-soldered connectors in service
> now with no problems so far. Both are in fixed
> service, zero coax movement.
> 
> --- Mahlon Haunschild <mahlonhaunschild at cox.net>
> wrote:
> 
>>Tom,
>>
>>Wussy irons like you describe will do what you
>>describe:  melt the cable 
>>without making a good solder connection to the
>>connector.  I used to use 
>>a Weller 200/240-watt soldering gun for PL-259
>>shells, but not even that 
>>beast put out enough heat.  These days I use a
>>butane mini-torch.  Much 
>>lighter and therefore easier to control.
>>
>>More heat is better than less in this case, at least
>>in my experience. 
>>The idea is to get the "hole area" of the connector
>>hot enough quickly 
>>enough so that you can solder the braid to the
>>connector shell quickly 
>>enough that the jacket/dielectric (esp. foam
>>dielectric) doesn't have 
>>enough time to melt.  Use a mini-vise to hold the
>>cable to position the 
>>connector so you can solder two holes with one
>>set-up.
>>
>>OK, you caught me at a weak moment:  here follows my
>>mystical PL-259 
>>installation procedure, developed painstakingly over
>>a LONG period of 
>>time:   Strip jacket/braid/dielectric CORRECTLY. 
>>Flux the braid with a 
>>small amount of GOOD flux (not that Rat Shack crap;
>>I use strain gauge 
>>flux).  Tin the braid with a soldering iron; use
>>only enough solder to 
>>do the job, excess will prevent installation of the
>>connector.  Cool the 
>>cable/braid w/damp rag.  Double-check the end to
>>ensure that no stray 
>>braid strands are where they shouldn't be.  Flux the
>>braid again.  Screw 
>>connector onto cable.  Place connector into vise
>>with the cable wound up 
>>1/2 turn.  Heat w/torch and solder holes 1 & 2. 
>>Release vise; the cable 
>>will by itself position for holes 3 & 4.  Heat
>>w/torch and solder holes 
>>3 and 4.  IMMEDIATELY quench the connector with the
>>damp rag.
>>
>>Using this method, I have not had a connector
>>failure in something like 
>>18 years.
>>
>>5 cents, please.  I accept PayPal.
>>
>>Oh, by the way: results not guaranteed on vinyl
>>cable jackets (but 
>>surely you don't have any of that, do you?).
>>
>>regards,
>>
>>Mahlon - K4OQ
>>
>>Tom Anderson wrote:
>>
>>>Fellow Tower Talkians:
>>>
>>>Any suggestions for a high wattage soldering iron
>>
>>good for using on 
>>
>>>PL259s (100 watts or so??)?   Most of the 25-40
>>
>>watt irons found in the 
>>
>>>mass hardware places (Home Depot/Lowes) seem to
>>
>>melt more die-electric 
>>
>>>than solder.  Anyone use/have any luck with opne
>>
>>of those Sears  100/400 
>>
>>>watt soldering gun?
>>>
>>>Tom, WW5L
>>
>>_______________________________________________
>>
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>>Towers", "Wireless Weather Stations", and lot's
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>>
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