PL 259 CONNECTOR

Has anybody ever had a problem with the good old PL259 where the insulation between the 'ground' side of the plug and the centre feed breaks down? I bought ten from Amazon and found them to appear well made. I used a couple for patch leads and found them to be a good connection. I then made my own antenna and couldn't understand why I was getting a complete rebound on the SWR. In my experience this relates to a 'dead short' between the two elements of the RG58 I was using. On checking the continuity this was confirmed. Checked the brand new previously unused coax and could find no obvious nicks or damage. Put another 259 on and same result. Dismantled the whole lot and had the idea to check the 259. Direct continuity between the centre pin and the body of the plug. I suspect that the soldering of the centre wire into the pin had 'melted' any insulation between the pin and the body. Has anybody come across this? Checked several of the supplied 259 and found a further three with the same problem even though I hadn't used them.

I ordered a couple of T-piece connectors from a third-party Amazon supplier and they are junk. The PL259 connector centre is a rod which just makes pressure contact with the "top of the T" metal bar between the two SO239s.

They weren't even particularly cheap!

I bought mine through ebay from uk4x4centre specifically because they said "Our PL259 have the Brown inserts which DON'T melt when soldering (unlike the cheap and nasty white inserts)"

I get decent ones made by Amphenol, not some generic no-name crap. What UK 4x4 Centre said was a load of horse manure and theirs are crap too.

Once you've had the Amphenol ones you'll soon realise that pretty much all of the ones that you can buy from the usual suspects are crap.

PL259 connectors get a bad rap because there are so many terrible ones out there!

The white inserts are good only if they are true 'Teflon', (capital T, usually with a 'trademark' or 'registered' mark), otherwise they're usually polypropylene which melt the moment you touch them with an iron!
The 'brown' inserts are typically polypropylene too! The myth being the white ones are rubbish but "our brown ones are best"......only if they are Paxolin or Tufnol are they actually better.

A lot of them today are 'stamped' out on some mass production Far Eastern factory, you can usually see the double seam along the thread....a decent cut one will not have such a seam. They usually have pressed inserts too causing the problems you stated.

When you consider having a decent radio, decent coax and a decent antenna, the chain breaks down with rubbish connectors!!!

I've always bought the best I can obtain, usually true Teflon and silver plated. Seems over the top but silver plating is a heck of a lot easier to solder to than trying to solder to cheap nickel plate, believe me.
You can also get PL259's with 'O' ring seals that are just the best if exposed to the elements such as SO239 connectors on commercial antennas.

Silver plate? 'O' rings? That equates to expensive, right?

The "useless" type are a couple of quid each? Expect to pay two to three times as much for decent connectors.


A price I think is worth paying for an important function such as your antenna connection

Avoid the cheap eBay rubbish, but also don’t just trust a connector because it is more expensive....a lot of shops just sell the same cheap, Chinese crap as the eBay sellers but at a far higher price!

I use only crimp/solder connectors these days (centre soldered, but crimped braid), and Amphenol (from somewhere like mouser.com) is a good compromise on price vs quality.

Just remember, your feedline is everything.....no point losing half your power into cable, a mismatch or a crap connector!

Just come 'back' to cb and was also thinking of amateur radio. Love to listen and try to learn. In my days (70s) there was very limited choice of where to get accessories from. I used to rely on my mates electrical shop in Salford (front for cb and Ham radio) but things were expensive. Seem to be spoiled now with outlets. Thank you for replying above - it's opened my eyes a bit. I suppose you get what you pay for.

Blue Boy wrote:

Thank you for replying above - it's opened my eyes a bit. I suppose you get what you pay for.

The thing is that until you try something better you don't realise what you were using was really like. I'd spent decades using probably the same PL259s as everyone else does and didn't think anything of them and that maybe it was me doing something wrong when I struggled soldering braid through the four holes on a PL259. Someone suggested using the Amphenols and as I was feeling flush I thought what the hell, I'll buy 10.

Even just putting the RG213 in you could tell the difference. Amphenol provide information showing you exactly how long to leave the centre exposed and the braid exposed and you put it in and it fits perfectly. A very slight resistance on coax outer insulation as you put it in. The shoulder just above the holes is the exact size so the braid goes through but the outer insulation fits flush. Proper silver plated too so soldering the braid through those holes takes seconds to do instead of you sitting there with an iron wondering if the coax will melt.

mind the new lead free solder is awful so I have good supply of the older solder and with the lead
is far better quality and I have the hard brown insulator pl259s and there very good i bought up lots when I seen them for sale the newer ones were very iffy .

stephen Gunrunner wrote:

mind the new lead free solder is awful so I have good supply of the older solder and with the lead
is far better quality and I have the hard brown insulator pl259s and there very good i bought up lots when I seen them for sale the newer ones were very iffy .

Yes the lead free is awful Stephen, I also have a stock of lead solder for when needed!

Ahh, you old farties
Solder was better in my day...made of proper stuff...poisons and lead and things...

Hee, hee!

Luckily ROHS compliance didn't cover the hobby use of 60/40 tin lead solders and is freely available
Mind you, the dishonest b*ggers that overcharged for it when the lead-free "scare" started was unbelievable!

Just looked around for different PL259's and was shocked at how much some places are charging for the rubbish ones!
Looks like these sort of problems aren't going to go away soon.

Right, this old fart is off to see if I have some old selenium rectifiers I can blow up and sniff

Ha Vic, you can't beat the smell of Rosin core solder flux! Mmmmmm!

Hee, hee! Couldn't agree more Gary.

God knows what they used on the old valve gear, those solder joints smell flipping remarkable when a hot iron touches them! Mind you, love the smell of old valve gear overall....my missus always gives me a strange smirk when she catches me breathing in the old valve radios!

It could be worse Vic, the mrs should count herself lucky!!!

I only have one bit of valve kit left a linear amplifier, when I fire it up which isn't very often the smell reminds me of our television when I was a kid, thank goodness for Radio rentals eh! Showing my age now Vic!!!

73's Gary.

Ha, ha, ha!!
Yeah, could be worse, maybe that's why she smirks

Love a good valve linear, you must try and hang on to it Gary.

Radio rentals.....threw me back. We had Granada round here, (with their massive offices too!), and I think Rediffusion as well.

Back in the day we only had three TV channels don't you know.

Just realised, it was the 'times' that caused all this! Weren't paying for a rental TV, fixed an old B&W set that cost me nothing and probably kicked off my electronics path. Plus there was usually nothing of interest 'on the box' so you switched on the old radio

Ahh, gonna wallow in some reminiscing for a while.......better check me pants, might be wallowing in something else!

Three channels??? You were lucky

Do you remember getting the new bbc 2 aerial fitted instead of the old H type one.(i do )

Ha, I'd completely forgotten about those H aerials but not the dot and whine from the screen on shut down!!

H antennas were awesome as everyone had one bolted onto their chimney, a veritable sea of antennas
Loads survived years after the VHF 525 service shut down......made it much easier for your transmitter antenna to go unnoticed

At least with the old TV service you could still watch your favourite program through the interference snow and odd lightning flash white line. Now the damn things stutter, pop up random coloured squares then up pops the 'no signal' box!
Even so called 'on demand' has you gritting your dentures at that s*dding magic ring buffering nonsense.

I think they call it "progress"

I do miss the simple pleasure of giving the old telly a thump and 'fixing' it though.