Which PL-259 connector?

[GTom]

I am redoing the VHF and AIS cabling and looking for some nice low-loss, watertight connectors.

I guess i have to look for a gold coated central pin, clamp nut+compressible gasket - something like this one. Anything else?

[Brian.D]

Those are Nickle plated. I would recommend Silver Compression PL-259. Yeah, more expensive, but I think in your environment they might last longer than Nickle. YMMV.

Even those are compression connectors, you are still advised to use double wall adhesive heat shrink tubing.

[Jammer]

No PL-259 connector is weatherproof. There isn't a gasket on the mating faces.


I like the DX engineering crimp/solder connectors where a PL-259 is necessary as when connecting to the radio: https://www.dxengineering.com/parts/dxe-pl259cs8u-12




If the connectors are exposed your best bet is to cut them off and use weatherproof connectors. N and TNC are among the many good choices. Silver plated is good.

[GTom]

Originally Posted by Brian.D

Those are Nickle plated. I would recommend Silver Compression PL-259. Yeah, more expensive, but I think in your environment they might last longer than Nickle. YMMV.

Even those are compression connectors, you are still advised to use double wall adhesive heat shrink tubing.

I'll only have a connector on the masthead and at the VHF kit keeping the cable in one piece. I read somewhere that Nickel becomes an issue at higher frequencies because of its magnetic properties, probably not a serious issue at 160MHz.

Originally Posted by Jammer

No PL-259 connector is weatherproof. There isn't a gasket on the mating faces.
I like the DX engineering crimp/solder connectors where a PL-259 is necessary as when connecting to the radio: https://www.dxengineering.com/parts/dxe-pl259cs8u-12
If the connectors are exposed your best bet is to cut them off and use weatherproof connectors. N and TNC are among the many good choices. Silver plated is good.

Neither VHF kits nor yacht antennas are made with N or TNC connectors. I dismissed the idea to cut the cable at deck level - in case I still do, I'd indeed use an N-connector. The VHF kit is inside anyway, I only need a proper connection to the Antenna, sitting on the masthead.

[Jammer]

Originally Posted by GTom

Neither VHF kits nor yacht antennas are made with N or TNC connectors [...] I only need a proper connection to the Antenna, sitting on the masthead.

1) Many marine VHF antennas come with a pigtail that has a connector on it or that is shipped loose to allow the pigtail to be fished through the mounting hardware. Either way, you can substitute a better connector, and you should, if it is going to be somewhere exposed to the weather.



2) If you have an antenna with a SO-239 connector that is integral with the base of the antenna, then your best bet is to use really good multi-wall heatshrink with an inner encapsulating adhesive over the whole thing after it is assembled.



All outdoor antenna and feedline systems have a finite life. Best practices lengthen it somewhat.


The "radio geek" approach to get maximum performance and longevity out of a masthead installation would be to install bulkhead N connectors through the side of the mast near the top and bottom, with Heliax running inside the mast between them. Then run an RG/400 pigtail from the upper connector to the antenna and from the lower connector to the radio. Done right it would be easily serviceable and the part inside the mast would last forever, and performance wise it would outperform RG/213.


But no one does that on a yacht because it's laborious and expensive, and not worth it.


It is a fairly standard approach on higher power, higher frequency systems on land, like cellular base stations and public safety radio systems.