PL 259 Connectors

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K8KPO

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We'll start with the TLDR:

Having bad luck with cheap PL-259 connectors and want something that won't make me want to scream.

Full version:

For my job, I've been soldering to DB-9 and DB-25 connectors for over 20 years. Have never had an issue. I bought some LMR-240 cable and some solder connectors (with reducers) thinking no big deal. I tried in vain to get the solder to stick to these things (the shield through the little windows) and had no success. I wondered if maybe they were coated with oil or something from the factory so I cleaned them and still nothing. Next option was to scuff up around the reducer to give some texture and the solder STILL won't stick to these things.

Are cheap PL-259 connectors really this bad or is there something about soldering these that makes them different from all the other soldering I have done? Are more expensive connectors better? If so, can someone please give me an example of something that will hold solder and can be used with LMR-240 cable?

I'm also considering crimp-on kind, but have actually become a little bewildered at trying to figure out how to get the right mix of connectors and tool/die to put on LMR-240 cable, so if anyone can offer hard advice on that I am definitely all ears.

I'm putting two (maybe three) new antennas up soon and I don't want to waste another hour+ trying to get solder to stick to something that apparently has super soldering-avoiding powers.

Any and all constructive advice is appreciated

EDIT: BTW, I have a coupon from www.gigaparts.com to use which would be nice assuming anyone can give links from there that they like, but if I need to buy elsewhere that's fine. I just want something good quality.
 

ka3aaa

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file off or scrape off the plating on the adapter that threads into the sleeve of the pl259, it will make your life a lot simpler. Solder the coax to the adapter first , then thread the adapter into the sleeve while holding the adapter into a pair of pliers , then solder thru the little holes after taking a drill bit through them toremove the palting.
 

fxdscon

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An interesting discussion on solder vs crimp for LMR240:

 
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GTR8000

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I assume that you're soldering the connector to the tinned copper braid, and not to the aluminum tape, correct?
 

W5lz

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I don't think you can get any better than Amphenol connectors, so that would be the brand I would get if possible. I've seen what you're seeing with the ones you have. Only thing that worked for me was to scrape off the coating they have, don't to the brass (or whatever).
 

K8KPO

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file off or scrape off the plating on the adapter that threads into the sleeve of the pl259, it will make your life a lot simpler. Solder the coax to the adapter first , then thread the adapter into the sleeve while holding the adapter into a pair of pliers , then solder thru the little holes after taking a drill bit through them toremove the palting.

Is there enough clearing to screw the reducer into the sleeve with solder on the side of the reducer?

You lost me on the drilling part. Are you saying after you screw the pieces together then you drill a hole through the windows and through the reducer itself and then toss solder through the newly created holes?
 

K8KPO

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I don't think you can get any better than Amphenol connectors, so that would be the brand I would get if possible. I've seen what you're seeing with the ones you have. Only thing that worked for me was to scrape off the coating they have, don't to the brass (or whatever).


I'm ok with paying $4 a piece if they are good and don't make me hate them. Can you offer insight on which reducer to use as the two listed there do not list LMR-240 as one of the options.

EDIT: The center conductor solders perfectly fine. It's just the shield to reducer portion that I cannot get solder to stick to.
 

Tech792

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No drilling. I think he means use a small drill bit like a file on the inside of the small holes to remove any plating.
 

prcguy

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A lot of PL-259s are nickel plated and your success with soldering requires a lot of heat and a good flux in the solder. I've abandoned those and only buy silver plated types these days, which solder real nice. I would also go with a silver plated pin over gold as the gold would be very thin.

On soldering to LMR coax, its very easy to damage it from heat, the foam dialectic will just melt away. Instead of assembling the connector and soldering the braid through the little holes I start with just the reducer and solder the braid to that very carefully first so you can inspect for damage. Then I assemble the connector leaving only the center conductor to solder. Otherwise any damage will be hidden inside the connector and you won't know until its too late.

I also don't pull a lot of braid back over the reducer, you only really need to bend the braid slightly over the reducer, then solder the shoulder of the reducer where the braid touches, then trim off the excess braid.

On LMR400 with no reducer I will prep the coax and braid, then quickly tin the braid before assembling the connector. Then with a silver plated connector and a very hot soldering gun you can solder the braid to the connector very quickly and have less chance of damage.

Better yet, get crimp connectors and be done with all the problems.
 

K8KPO

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Ok, so what about this:


In the notes it says "Notes: Furnished with die set for RG-8X/LMR-240 cables."

And then these:


which says "Fits all standard RG-8X size cables including DXE-8X, LMR-240 as well as RG-59, RG-62 and many others, including Belden 9258, 8241, 1505 and 7808 series"
 

prcguy

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Looks reasonable to me. I would also get some 3/8" OD hot glue heat shrink and use a piece about 1.5" long at each crimped connector as a strain relief.


Ok, so what about this:

[/URL]

In the notes it says "Notes: Furnished with die set for RG-8X/LMR-240 cables."

And then these:

[/URL]

which says "Fits all standard RG-8X size cables including DXE-8X, LMR-240 as well as RG-59, RG-62 and many others, including Belden 9258, 8241, 1505 and 7808 series"
 

WA8ZTZ

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Have used the DX Engineering Next Generation Crimp/Solder Pl-259 connectors with RG-213 coax with good success.
The center conductor is soldered to the pin (easy) but the troublesome soldering of the outer braid is eliminated and crimped instead...
makes a sometimes PITA job a breeze. This connector would be especially nice if you are using foam dielectric cable as the foam will start to melt if the braid gets hot. Crimping the braid eliminates this concern. IMHO, once you have used the DXE connectors you will never go back. ;)
 

iMONITOR

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I don't think you can get any better than Amphenol connectors, so that would be the brand I would get if possible. I've seen what you're seeing with the ones you have. Only thing that worked for me was to scrape off the coating they have, don't to the brass (or whatever).

I couldn't agree more. I used to sell Amphenol connectors back in the 60's for Radio Specialties Electronics in Detroit.
 

K8KPO

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I ordered the DX Engineering set. I shall make a final report once I've used it so that any future askers will know the final outcome.
 

ko6jw_2

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I always get silver plated connectors and use a 250 watt soldering gun. It takes a while to heat up the connector, but the solder flows freely. With LMR-400 I've gone to crimp on connectors. The center pin is soldered, but the braid is crimped. Need a special tool, but way easier than the older types. Stay away from the cheap connectors with Teflon insulation. I've had them melt while soldering the center pin even with a low wattage iron.

Better yet use N connectors. Easier to attach and better at UHF.
 

W5lz

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Soldering the braid, I don't bother. if using a reducer you might tin it first, then just fold the braid onto it, put the rest of the connector together then put a small drop of solder in one or two of those holes. The mechanics will keep the braid in contact and that's all you need. For use without the reducers I just maybe put a drop of solder in the holes, I don't tin the braid, that's never worked for me. I also learned to put those connectors on with a propane torch. That's certainly handy on a tower, for instance. [The reducer for RG-58 will work fine with LMR-240.]
As for the crimp on connectors, I don't use them. I've seen them work just fine, but I'd rather do the soldering.
 

Ravenkeeper

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I've used both, solder/solderless, and still ended up putting some solder down the core, connection was intermittent. Never had any issues with the shielding side of them.
 

prcguy

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I know it might seem like I'm picking on you Bob, but the advice below is not a good idea for a professional long lasting install. If you want to put on PL-259s without soldering the braid on your own equipment, that's great, but there are people here trying to learn stuff and its better to tell them the industry accepted way of doing it. If you hired a professional to install connectors on your stuff and they did what you posted, would you be happy?

And for most people a crimped connector is superior unless the wrong crimper is used. In fact, when I worked on huge aircraft wiring harness, soldered connectors were outright prohibited even though most of our crew was NASA certified in soldering. We could only use crimp type.


Soldering the braid, I don't bother. if using a reducer you might tin it first, then just fold the braid onto it, put the rest of the connector together then put a small drop of solder in one or two of those holes. The mechanics will keep the braid in contact and that's all you need. For use without the reducers I just maybe put a drop of solder in the holes, I don't tin the braid, that's never worked for me. I also learned to put those connectors on with a propane torch. That's certainly handy on a tower, for instance. [The reducer for RG-58 will work fine with LMR-240.]
As for the crimp on connectors, I don't use them. I've seen them work just fine, but I'd rather do the soldering.
 
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