RG6 connector???

[stephen_h]

Hi,

I have had to move my stand alone AIS aerial and re-route the coax cable.

In order to achieve this I had to cut of the fitting that goes to the aerial.
Pictures below - black outer cover removed while trying to remove the plug but it seams to be glued in?

I believe the cable is RG/Series 6 coaxial - 6mm diameter.

This plug just gets pushed into the underside of the aerial and then has a seperate plastic cover that screws on the holds it in place.

Any idea what the plug is and where I can get some?

Thanks, Steve

 

[ProDave]

That looks to be crimped on and by someone without the proper tool using pliers and a vice.

I would not have cut it short like that, I would have left more of a tail and used an in line BNC plug and socket.

Heaven knows where you will find a replacement non standard connector like that. Post a picture of the receptacle.

Try an F connector in line socket to socket or sometimes known as a couple, that might not be far off and could be the basis for modifying it to fit?



If the centre pin of that is the right size but the body is wrong you could turn one end down on a lathe to fit then a standard F plug would go in the other end.

Just s suggestion might be totally wrong but I can't think of any other female connector of similar size

 

[stephen_h]

That looks to be crimped on and by someone without the proper tool using pliers and a vice.

I would not have cut it short like that, I would have left more of a tail and used an in line BNC plug and socket.

Heaven knows where you will find a replacement non standard connector like that. Post a picture of the receptacle.

Try an F connector in line socket to socket or sometimes known as a couple, that might not be far off and could be the basis for modifying it to fit?

View attachment 183157



If the centre pin of that is the right size but the body is wrong you could turn one end down on a lathe to git then a standard F plug would go in the other end.

Just s suggestion might be totally wrong but I can't think of any other female connector of similar size

The damage was done by me trying to remove the cable

 

[PaulRainbow]

Looks similar to one of these, might be adaptable ? VTronix and Shakespear ACC158 Solderless Connector Termination Kit YSC

What AIS do you have ?

 

[wonkywinch]

Try an F connector in line socket to socket or sometimes known as a couple, that might not be far off and could be the basis for modifying it to fit?

I strongly recommend you don't use an F connector. After buying our boat, the AIS transceiver received traffic within a mile or two but was not visible to any boats close to us nor the ground stations that feed Vesselfinder etc.

All connections were sound but I found an F connector with joiner as per your post in the ceiling at the base of the mast. I swapped it for a PL259 and the difference was astounding. Receive AIS traffic 20 miles away and the transmit function worked perfectly. The VSWR of the F connector must have screwed things up at the VHF frequency used by AIS.

 

[rogerthebodger]

The F connector is used on satellite dish being a much higher frequency that VHF

 

[wonkywinch]

The F connector is used on satellite dish being a much higher frequency that VHF

They, and the RG6 cable also has a design impedance of 75 ohms. Marine radio antenna design is based around 50 ohm so the connector and cable are creating a mismatch.

 

[stephen_h]

Looks similar to one of these, might be adaptable ? VTronix and Shakespear ACC158 Solderless Connector Termination Kit YSC

What AIS do you have ?

That's the one, exactly the same fittings - one on order now

Thanks for all the answers

 

[ProDave]

I strongly recommend you don't use an F connector. After buying our boat, the AIS transceiver received traffic within a mile or two but was not visible to any boats close to us nor the ground stations that feed Vesselfinder etc.

I was trying to suggest a possible connector or one that could be adapted for what I thought was an unknown unobtainable proper connector. the link subsequently posted may be the correct thing.

The F connector being 75 ohm instead of 50 is not perfect but no worse than a PL259 and that on it's own would not result in massively poor performance, you must have had a poorly made or corroded connection.

 

[wonkywinch]

you must have had a poorly made or corroded connection.

Nope, it was clean, dry and freshly made up when I reconnected everything after mast step.

Friends who are electronics comms experts suggested changing the connector and to my surprise it had such a drastic effect. Nothing else altered so only speaking from first hand experience.

I am also a radio amateur and should have known this but my exam pass was more than 50 years ago.

 

[ProDave]

I am also a radio amateur and should have known this but my exam pass was more than 50 years ago.

In which case you will surely know a PL259 is not a defined impedance connector and regarded as pretty rubbish for VHF. For just joining 2 small cables I would have used a BNC plug and socket available in 50 ohm and 75 ohm (different pin sizes) and for larger cables, N type.

 

[st599]

In which case you will surely know a PL259 is not a defined impedance connector and regarded as pretty rubbish for VHF. For just joining 2 small cables I would have used a BNC plug and socket available in 50 ohm and 75 ohm (different pin sizes) and for larger cables, N type.

Sometimes you're lucky and a PL-259 is almost 50 ohms, but a 75 ohm connector would be better as you suggested. With a 50 to 75 mismatch you'll be losing a small but not insignificant amount of power being reflected (my brain is saying 5%)

 

[wonkywinch]

In which case you will surely know a PL259 is not a defined impedance connector and regarded as pretty rubbish for VHF. For just joining 2 small cables I would have used a BNC plug and socket available in 50 ohm and 75 ohm (different pin sizes) and for larger cables, N type.

I thought I'd use 259s as this is what B&G chose on the AIS and splitter I was wiring up. Plus I had some to hand and no N types nor BNCs.