In line VHF radio coax cable connector.

[john_morris_uk]

BNC are fine, but you need the special crimping tool and they are fiddly.

Post #11 is a good solution, or a pair of solderless PL259s with a barrel connector (given the OP has no soldering facilities).

Plenty of non crimp BNC’s available but they require soldering the central connecting pin. Crimping ones require the proper crimping tool. Best RF performance is with a good quality BNC that’s meticulously put together. There are some poor quality ones around and the best ones are silver plated. However we’re starting to gild the lily a bit here and a pair of PL259’s with a barrel connector will work very well. They’re not as good as BNC’s as far as the RF is concerned but the OP won’t notice the difference. Again, the centre connector really ought to be soldered.

Many years ago when I worked at the Royal Radar Establishment as a junior scientific officer I used to measure the performance of RF connections. Of course N connectors are even better but their quality also varies and who is putting it together actually makes a difference….

There are non solder 259 connectors ....

I would not use a BNC .... not really designed for this job ...

I’ve not seen a non solder PL259. BNC is perfect for this job and they were designed to connect small diameter coaxial cables. No idea why you suggest they weren’t.

 

[Refueler]

Plenty of non crimp BNC’s available but they require soldering the central connecting pin. Crimping ones require the proper crimping tool. Best RF performance is with a good quality BNC that’s meticulously put together. There are some poor quality ones around and the best ones are silver plated. However we’re starting to gild the lily a bit here and a pair of PL259’s with a barrel connector will work very well. They’re not as good as BNC’s as far as the RF is concerned but the OP won’t notice the difference. Again, the centre connector really ought to be soldered.

Many years ago when I worked at the Royal Radar Establishment as a junior scientific officer I used to measure the performance of RF connections. Of course N connectors are even better but their quality also varies and who is putting it together actually makes a difference….

I’ve not seen a non solder PL259. BNC is perfect for this job and they were designed to connect small diameter coaxial cables. No idea why you suggest they weren’t.

Non Solder 259 .... the centre pin uses a tiny screw to lock the centre wire .... had a few over the years ... they are longer due to this.
Of course if access to soldering - then soldered versions are easy to source.

Why I am against BNC ... most BNC over counter are poor quality and often not corrosion proof / resistant. Its fine if you can get good quality. Second that usual over counter are 75ohm not the 50ohm we need. BNC are of two versions .. 50 and 75ohm.

 

[Refueler]

On my 25ft boat - until a few years ago - it had survived with a 'spliced' co-ax ..... had been done by one of the previous owners and then later when I changed antenna - I repeated it.... then later replaced it with a continuous cable from deck plug.

Basically the two centre wire ends had been solder joined .... then old insulation folded back over and taped to recreate the cable ... SWR meter showed exact same readings of that - as later with a new continuous cable.

 

[john_morris_uk]

Non Solder 259 .... the centre pin uses a tiny screw to lock the centre wire .... had a few over the years ... they are longer due to this.
Of course if access to soldering - then soldered versions are easy to source.

Why I am against BNC ... most BNC over counter are poor quality and often not corrosion proof / resistant. Its fine if you can get good quality. Second that usual over counter are 75ohm not the 50ohm we need. BNC are of two versions .. 50 and 75ohm.

All true but you said they’re not designed for this application? Easy to make sure you buy a 50 ohm impedance one.

Regarding quality, you get what you pay for.

 

[RobWard]

Just sayin' - I bought a gas soldering iron for about £40 from F4, as well as soldering it's surprisingly useful as a blow torch (heat shrink etc) and rope cutter...

 

[Refueler]

Just sayin' - I bought a gas soldering iron for about £40 from F4, as well as soldering it's surprisingly useful as a blow torch (heat shrink etc) and rope cutter...

Butane / Propane soldering irons can be found much cheaper than that and likely same manufacturer !

But they are a great tool .... especially if you buy the set that has hot knife and other attachments.... not only for soldering.

I also have a 12v iron ... which amazed me when power lead to starter solenoid failed one trip ... while drifting - with 'tongue in cheek' tried the 12v iron to join the lead back to the connector on the solenoid ... it not only worked but that lead was good for rest of season !

 

[CJU]

I have bought various bits & pieces from this company. They are knowledgeable and easy to deal with, especially over the phone. Marine

 

[Dunx]

The way co-axial works is that an RF Field travels along the cable in the dielectric between the inner and the outer. The cable is 50 ohms, if the field encounters a different impedance (caused by say a different size inner or dielectric, a gap in the shield, a change in shape), some of it is reflected back towards the transmitter. So your connection would work, but it would decrease the power being transmitted, and if the mismatch is big enough, could cause the radio to reduce power to protect the output.

Much easier to solder a decent connector on each end and add a barrel.

Can anyone advise please. I need to make an emergency repair to to coax for my AIS. The cable has been cut directly below the antenna where it exits a stainless tube. The coax cannot be replaced to the antenna base as it is moulded in. I cannot fix a connector to join the cable as there is not enough cable left and on anycase it also runs through a stainless tube. Can I solder the inner cable together as a temp fix to get me home or does that put the AIS unit at risk?

 

[Daverw]

Its not an easy one to do, but can be done if you have enough slack, you need to solder the inner core and place a short section of the insulator around it, then span the gap with tin foil to connect the outer braid and they cover with tape, your AIS is low power so should still work and if the swr is way off will tell you, just make sure you keep inner and outer separated