VHF Radio No Range

[gearyg]

Hello, I have a Shakesphere 3' Powered antenna connected to a fixed mount VHF radio. When I am out, I can hear and talk to another boat, but only if they are no farther than 50 yds away. I can hear them, but they can't hear me up to about 150yds away. I need to get this fixed, but cannot figure out if it is the Antenna or the Radio that is busted....anyone out there ever experienced the same...thanks.

 

[madgadget]

Re: VHF Radio No Range

Most likely antenna/coax if both TX and RX are poor.

 

[gearyg]

Re: VHF Radio No Range

Most likely antenna/coax if both TX and RX are poor.

Thanks but please excuse my ignorance, what is the TX and RX?

 

[Splat]

Re: VHF Radio No Range

Transmit and recieve.

Is your antenna mounted uprigh when using it, and not in the down stored position?

Are your connectors in good clean condition. Did you install your connectors yourself, or were they installed on the cable for you?

Bill

 

[gearyg]

Re: VHF Radio No Range

Transmit and recieve.

Is your antenna mounted uprigh when using it, and not in the down stored position?

Are your connectors in good clean condition. Did you install your connectors yourself, or were they installed on the cable for you?

Bill

It is in the upright position when I am out. The connectors look ok...no rust or corosion. I did not install them myself, they were there when I bought the boat. Based on the replies that I got, it seems that I should start with the connectors (replace) and then work torwards the antenna before I replace the VHF unit itself.

 

[madgadget]

Re: VHF Radio No Range

I would say with the kind of reception your getting there may even be a short in the coax. Its acting as if it doesn't have anything connected to it at all.

I would advise not to try and transmit (RX) on that until you have it working better or you risk frying the output in the transceiver.

 

[jhebert]

Re: VHF Radio No Range

...I have a Shakesphere 3' Powered antenna ...

I have never heard of a "powered" antenna. Please give more details.

You can evaluate the receiver portion of your radio by listening for NOAA Weather Broadcasts from distant stations. I explain the method in an article:

Assessing VHF Marine Band Antenna Performance Using Remote NOAA Weather Radio Broadcasts

http://continuouswave.com/whaler/reference/antennaRange.html

 

[Overnighter20]

Re: VHF Radio No Range

just curious, is your radio of the most common 25w/1w variety, and if so is it possibly only working on 1w instead of 25w?

 

[Boatist]

Re: VHF Radio No Range

It is most likely the antenna or the coax but some details of what you have would help.
To help isolate the problem a SWR Bridge and a dummy load would be the ideal way.
Assume you do not have either so here a few thing your can do to help isolate the problem.

First a good Idea to check the voltage at the radio's power plug.
It should be between 11 and 14 volts.
If you do not have a volt meter either then try this.
Remove the radio from it's mounting and take a piece of wire like 12 guage house power wire and about 39 inches long.
On the end double it and push it into the center pin where the coax attaches to the radio.
Then about 1/2 inch behind the connector bend the wire 90 degrees so the wire will go straight up.
Put the radio in 1 watt mode and turn it on. Do not transmit. Make sure your new wire antenna does not hit anything metal.
If you are in an area with a lot of VHF activity then put the radio on Channel 16,or 68, or scan if it has a scan feature.
You should be able to here other boats for a couple of miles.
If your area does not have a lot of radio traffic then set to the weather channel and try all the Channels.
For good reception radio and antenna should be up on the deck or at least out of any metal cabin.

Make sure the volume is turned up and set the squelch to the point where static just stops.

If the radio recieves in this mode better than it did with the antenna then the problem will be the antenna or Coax.

If you have a friend who is a Ham Radio operator then they will likely have a VHF SWR Bridge and can help you.
A CB SWR BRIDGE will NOT WORK.

When I go to the Ocean on a Fishing trip I always take 50 of Coax, a VHF SWR bridge and
a dummy Load plus a PL258 connector so I can help people with their radios.

I will tell you 90 percent or more of the people I have helped the problem was the Coax or Antenna.
Commons problems are the PL259 connector soldered on is shorted.
Either the braid is shorted to the center connector or they used too much heat and melted the center coax insulation.
Another problem is where the coax goes thru the cab or deck to get out to the antenna.
Again it is shorted to the aluminum deck or window where it comes out or the coax cover is broken or cracked and water got into the cable.
Another place that fails a lot is where the Coax flexes when the antenna is layed down.
People make that bend to sharp the coax breaks inside in short time.
Another very common problem is the small felexable antenna the Radiator inside the antenna breaks.

Is your radio new enough to have the DCS button?
What brand is the radio? What brand and type is the antenna?