VHF connector hack

[jwag956]

We have a fairly new VHF radio (Horizon Matrix) - realized that it really wasn’t receiving well (e.g. couldn’t hear/receive WX broadcasts even though our handheld was fine). Unscrewing the VHF coax and wiggling it around - and all was well - until I screwed it back in.
No problem - must be the old coax wire - bought new one and screwed in - alas same thing - which sort of implies that the radios connector is somehow messed up (can’t actually see it since its mounted up high).

I’d rather not replace a newish radio - any hacks that could make this a reliable connection?

Thanks.

 

[Comodave]

When you say you replaced the coax wire, what exactly do you mean? Did you put in new coax from the antenna or did you replace the PL259 connector?

 

[STB]

I'd suggest putting an SWR meter by the radio to check the antenna and path to it. I'm betting there is a high SWR meaning the problem is outside of the radio.

There may be connections or splitters or waterlogged cable or the wrong type of cable between the termination on the radio end and the antenna. Or the antenna could be bad.

I'd measure it before I bet on the radio being the problem.

SWR meters are cheap on Amazon. You can also use an antenna analyzer, also available on Amazon, which can inject a signal so you can test compleey independent of the suspect radio.

 

[jwag956]

So - it's about 2' from the antenna splitter to the radio - the other radio connected to the splitter is great (considering its 20+ years old!). I simply replaced the entire cable with a store bought (seadog) cable. As I mentioned - loosening the cable and wiggling it I can get the 'appropriate' reception.

thanks for the suggestion on SWR tester - I'll look into that.

 

[STB]

The ends on those connectors can be more tricky to get right than one might think. If I had a guess...

 

[Comodave]

I would take the splitter out of the circuit and run the antenna cable directly to the radio.

 

[Olebird]

PL-259 UHF connectors have, for years, have been a curse for most who try install them. First, the quality of the connectors proper varies all over the map. Don't scrimp and buy only from a known HQ source. Installation seems to be simple and intuitive --BUT IT'S NOT! I recommend you buy UHF connectors and cable only from DX Engineering - and pay the price. DXE-PL259CS8U-12

Do not try to solder them on --use only their crimp on design - buy or borrow the recommended crimping tool and follow their instructions or have your local certified tech install them.


I'm a Navy Solder School grad and I screw up the old solder style 7 out 10 times.


Your radio can be a life line and a bad connector is a ten dollar part that can ruin you whole day -




https://www.dxengineering.com/parts/dxe-pl259cs8u-12 (instructions on the same page - no financial interest on my part

 

[Olebird]

PS - most radio performance problems I see are poor pl259 connector installs!



Keep the splitter, it's there for a reason.



SWR meters are handy but not fool proof - you have to know what you're looking at.

 

[psneeld]

I would get rid of the splitter if it is being used for the 2 radios to one antenna.

If you only have 2 radios each should have its own antenna.

If the other radio and the antenna are 20 years old, they would probably go too.

I an not usually one for tossing stuff, but today's radio tech and features outweigh a lot.

 

[Always Late]

The first and obvious thing to try would be swapping the radios before buying meters and pl-259's and see if the newer radio works on the old radio antenna connection.

 

[High Wire]

Connect the antenna lead directly to the vhf in question to see if the problem goes away. Bet it does.
Is the splitter designed for two transmitters?

 

[diver dave]

…..Unscrewing the VHF coax and wiggling it around - and all was well - until I screwed it back in.

No problem - must be the old coax wire - bought new one and screwed in - alas same thing - which sort of implies that the radios connector is somehow messed up (can’t actually see it since its mounted up high).



..,,.

Manytimes this happens with a center to shield short. Hard part is finding it.

 

[jwag956]

Thanks to all - as I posted in #4 - I replaced the cable with a store bought (seadog) one - so hopefully not connector issues. I have swapped splitter outputs - no change. I have not done the other A-B tests that have been suggested. More to explore when we get back on the boat.
As to the 2 radios - 2 antennas - I *believe* both radios are fed from one antenna - the other antenna feeds the AIS?

 

[STB]

Ah. Okay. I've never bought a cable with a connector already on it! I Always out on my own, just so I get the size right.it would be rare for a factory made one to be bad.

If you have two manufacturer's ends, you can flip the ends of the cable and verify that the problem doesnt go away and that the instability doesn't flip ends, just to check the cable to be really sure.

If that's the case, you have really isolated it to that radio. I'd take a really good look at the connector on it to make sure there is no debris that could be causing a problem. Beyond that, I guess options are take it apart and fix it, have someone else take it apart and fix it, replace it, or find a little boy to use his thumb (like the dike).

The splitter between VHF and an AIS receiver is a common solution, well-liked by many (I, personally, prefer a 2nd antenna because it is often cheaper and is more redundant).

Just for a totalnassumptions check, which cable did you replace? (There are at least three, right? Antenna to splitter, splitter to AIS, and splitter to VHF.) On the odd chance that it wasn't the splitter to VHF, try that one.

 

[Duke of Patch]

Obviously if you can get good occasional reception by wiggling the connector, theres something wrong with the connector/wire termination - not the antenna or the splitter. Take the connector off and try again. These are tricky to get them soldered correctly ( the braided shield ground soldering being the most difficult) as it takes a lot of heat to avoid a cold solder joint but you may melt the center wire insulation in the process and create a short. You can use a small propane torch or a 250 watt solder gun. There is a small possibility that the connector on the radio itself is faulty. Try to solder again fist or buy a crimp on style..best luck

 

[jgwinks]

If you narrow it down to the radio, likely there's a wire from the inlet connector to the circuit board, held on to the connector with a nut or something. It could be loose. Ground is usually just the ring nut holding the connector to the chassis. Also could be loose or corroded. There's probably just four screws holding the radio together, opening it up is easy.

 

[alormaria]

I would take the radio out and drop it 2 foot down onto a concrete floor padded with a thin sheet of cardboard.


Always worked for me.

 

[diver dave]

I seem to remember fixing a HF mobile coax connector that the center conductor went directly to the PCB, without benefit of a short coax to absorb stress. A cracked joint there would cause your symptom.

 

[jwag956]

Update - got back on board finally - did some more A-B testing.
Antenna direct to radio - works.
Antenna through splitter (Shakespeare AR-2) - one output works the other doesn’t.

Started looking for what to do - new antenna (most folks on this forum think that is the best solution). Just replace the splitter - easiest by far…
Started reading comments about the AR-2 and it finally clicked - those splitters have a electro-mechanical relay that connects one radio OR the other to the antenna.

I had tried keying the mic - but I had it on the WX channel since that was my ‘test receive’ channel - but of course the radio knows it’s a non-transmit channel!

So long thread short - everything works just as designed - time to update my ‘flybridge checklist’.

Thanks for all the pointers and help.

 

[jgwinks]

I was wondering about the splitter. If was just a plain splitter keying one radio would blow up the other, they don't like 25 watts going the wrong way on the output. So when you key one radio the splitter automatically switches to that input? I'm not familiar with those but it sounds right.

 

[Duke of Patch]

Update - got back on board finally - did some more A-B testing.
Antenna direct to radio - works.
Antenna through splitter (Shakespeare AR-2) - one output works the other doesn’t.

Started looking for what to do - new antenna (most folks on this forum think that is the best solution). Just replace the splitter - easiest by far…
Started reading comments about the AR-2 and it finally clicked - those splitters have a electro-mechanical relay that connects one radio OR the other to the antenna.

I had tried keying the mic - but I had it on the WX channel since that was my ‘test receive’ channel - but of course the radio knows it’s a non-transmit channel!

So long thread short - everything works just as designed - time to update my ‘flybridge checklist’.

Thanks for all the pointers and help.

never was aware the splitter had a microswitch-most people install a separate antenna as a 100 % back up. I used a splitter for a VHF/FM setup. Makes sense if the splitter was designed for 2 VHF radios as damage would occur to the receiving radio without it.

 

[trainermb]

I would take the radio out and drop it 2 foot down onto a concrete floor padded with a thin sheet of cardboard.


Always worked for me.

Percussive maintenance.