VHF radio or antenna problem

[John_F]

I can't tell if my VHF radio is broken, or if the antenna isn't working. I was told to use an SWR meter but can any idiot like me figure this out? I have no electronic or radio background. Would the SWR meter be able to troubleshoot if my issue was with the vhf radio or with the antenna?

Also, a couple years ago I had the mast unstepped so I am not sure if the antenna wasn't connected properly at the top of the mast. Would the SWR at least be able to tell me if it might be the connection before I risk my life and go up the mast?

 

[Tally Ho]

If you have a spare antenna, you could connect it temporarily, with a short cable, and test by talking to a local, close boat ( or your own hand-held). You won’t get as much distance, but you should be able to talk to someone close if the radio is working.

If that fails, then I would think the radio is bad.

if it works, then either the cable or antenna is bad.

Greg

 

[John_F]

Thanks!

 

[Don S/V ILLusion]

Good suggestion to try a different antenna and you could also connect a different radio to your existing antenna system as another way to isolate the problem.

An SWR meter will tell you whether it is a radio problem or an antenna problem as it measures both output power of the radio as well as reflected power from the antenna/coax. The only complication of using an SWR meter to measure power output is that any contemporary VHF radio is d signed to fold back power into a mismatched load which can serve to mislead someone who doesn’t know that.

 

[dlochner]

What are the symptoms that make you question whether the radio or antenna has failed?

 

[Ken Cross]

Stick The stripped end of 18 inch piece of wire into the center where the coax connects to the radio. Do NOT transmit, but tune in something to listen to. While you are listening, remove the wire which should kill the signal. Then hook up your VHF antenna If it comes back you have a somewhat working antenna. The main purpose of a VSWR meter is to determine how good the antenna is. If it weren't hooked up it will be obvious doing this test I just referred to. Your antenna on the boat should work better than the 18-in piece of wire. So it should pick up weaker stations than the wire. If you need help beyond this, send me a PM and I will send you my phone number.

Ken

 

[JohnShannon]

I have the impression that a marginal antenna will receive and fool you into thinking it is OK but it won't transmit worth a darn.

 

[dlochner]

Check the settings on the radio. Make sure you are on US channels and not International or Canadian. The frequencies are slightly different and it will appear that the radio isn't sending or receiving if the setting is on International frequencies. Voice of experience.

 

[Ken Cross]

I have the impression that a marginal antenna will receive and fool you into thinking it is OK but it won't transmit worth a darn.

Technically the effect of a poor antenna or transmission line to a receiver and the effect to a transmitter are exactly identical. That's why you make yourself a small test antenna with a piece of wire to compare it with the antenna on the boat. They boat antenna should be more sensitive than the wire. I know this is a poor man's method and I'm assuming they don't have a VSWR meter. Yes I have done this test and it works very well but then I have a lifetime of radio work behind me.

 

[NYSail]

Another good place to start is your mast fitting where vhf is spliced for mast removal. When I bought my boat had horrible reception. Inspected the fitting and found it looking not so good. Cut out and redid with new fitting and radio works great.


Greg