VHF not hearing long distance

[Xavierp]

Hi all
This morning I did a radio check with the USCG.
Their boat was next to me and we could converse via the radio
However their main station was hearing me but I could not hear them

AIS working fine

Simrad RS40

Thx!

[Jammer]

Feedline problems, most likely at the connectors.

[Tin Tin]

Have you got an emergency antenna? If so, swap it out and see what happens. Check connections. Try by-passing AIS splitter and see it it works (Ie connect antenna directly to radio) If in port buy a SWR meter to check your antenna about $30 for a cheap one.

[ohgary]

What do you consider long range?

An antenna at the top of a 50ft mast talking to a coast guard stations with an antenna at 100ft, only gives you around 24miles of range. Longer range is possible and common
but has some limitations as well. Local noise, coax quality or state of repair can affect those as well.

Issue could also be on the coast guard side, to many signal and your not the top signal they are hearing.

[Xavierp]

Originally Posted by Jammer

Feedline problems, most likely at the connectors.

I changed one this weekend. And took apart the other to see how to do install the new one
I probably didn’t put it back correctly and/or not installed the new one correctly

Thx!

[Xavierp]

Originally Posted by Tin Tin

Have you got an emergency antenna? If so, swap it out and see what happens. Check connections. Try by-passing AIS splitter and see it it works (Ie connect antenna directly to radio) If in port buy a SWR meter to check your antenna about $30 for a cheap one.

No spare antenna and not sure where the ais splitter is. I guess I have to unmount the radio
Will consider the SWR meter

Thx!

[Xavierp]

Originally Posted by ohgary

What do you consider long range?

An antenna at the top of a 50ft mast talking to a coast guard stations with an antenna at 100ft, only gives you around 24miles of range. Longer range is possible and common
but has some limitations as well. Local noise, coax quality or state of repair can affect those as well.

Issue could also be on the coast guard side, to many signal and your not the top signal they are hearing.

Hey Gary. The coast guard office was less than 5 miles.amd they could hear me. I need to look at the connectors but it’s not easy to see if they are good enough or not

[Jammer]

Only way to know for sure is with a vswr meter or a VNA. You can get cheap ones, or borrow one from a friend.

[leecea]

Is it possible that a high squelch setting could cause this?

[S/V Illusion]

The symptoms of bad or poor connection or bad coax would manifest more during transmit than receive. Either would cause reduced power and therefore reduced range while a problematic feed line would still receive albeit not as well.

The actual cause of what you describe can’t be ascertained with the limited info you mentioned although that apparently doesn’t prevent some people from making wild guesses.

Simply “looking at the connectors” won’t reveal a poor solder connection, moisture in the braid, etc…

[hjohnson]

Originally Posted by ohgary

What do you consider long range?

An antenna at the top of a 50ft mast talking to a coast guard stations with an antenna at 100ft, only gives you around 24miles of range. Longer range is possible and common
but has some limitations as well. Local noise, coax quality or state of repair can affect those as well.

Issue could also be on the coast guard side, to many signal and your not the top signal they are hearing.

It can really depend on atmospherics too. A couple weeks ago, I was sailing off the Brooks Peninsula on the north-west coast of Vancouver Island, and we started seeing AIS contacts from the Columbia River and Portland. We later heard US Coast Guard Station Tilamook announcing the bar conditions, so for gits and shiggles, we called them back with a signal reception report. I think we confused the hell out of the poor woman when we gave our position as somewhere that wasn’t even on her charts.

Those epic conditions lasted for about two days.

[Xavierp]

Originally Posted by leecea

Is it possible that a high squelch setting could cause this?

Squelch level is all the up
I’ll bring it down

[hjohnson]

Originally Posted by Xavierp

Squelch level is all the up
I’ll bring it down

That would do it. You want the squelch just high enough that the radio isn’t busting into static all the time.

[Xavierp]

Originally Posted by S/V Illusion

The actual cause of what you describe can’t be ascertained with the limited info you mentioned although that apparently doesn’t prevent some people from making wild guesses.

I think people are genuinely trying to help by throwing ideas. And I really appreciate that

What do you think I could do?

[lifeofreilly57]

Theres no magic bullet here.
Basically, if the radio itself is not suspect then it's somewhere in the cabling or antenna itself.
Easiest is checking the connectors, including the one at the antenna at the mast.
Since your going up the mast, use an ohm meter to test the cable end to end. The easiest way is to use a long piece of wire and the meter, have the meter connected to the wire down on the deck, where the person helping you can use it. The person down below can attach it to the center conductor while you do the same up above, then move the connection to the outer conductor/ shield. Compare the values.
Most coax cable has 50 ohms or 90 ohms of resistance depending on the type.
RG 6 is popular but there are a couple different types. You can usually tell the type by looking at the cable itself, it's usually printed on the cable.
This will serve the purpose of inspecting the connections and testing the cable at the same time.
In the past I've had both bad connections and cables. Once corrosion sets in it's just a matter of time.
If the connections and cable are good, then test the splitter, is it a powered splitter or not? Yes I've had one of those fail too.
Trouble shooting is a process of eliminating what isn't failed, til you find what did fail.
If your taking the trouble to test the mast top cable connection/cable take some dielectric grease with you, use it liberally on the connection before screwing it back to the antenna.
Rust never sleeps, on a boat everything corrodes eventually.
Just for giggles I kept stripping back one failed coax cable once, the corrosion extended 11 feet back from the connection at the mast, much of it just crumbled when I stripped the covering off.
Don't know how the previous owner didn't pick up on his lack of range.
Just a thought, could it possibly be the mic on the radio? Yup, had that happen too. If your radio has a remote mic, try it and see if there's an improvement.
Oh, I also have had an antenna base fail from corrosion. There's not much to them but like all things on boats they can corrode and cause issues too.
I usually pull the mast every few years for inspection and servicing, at that time I'll just replace the mast wiring, it's cheaper than trying to fix it once the mast is stepped.