VHF - No Sound

[Jimske]

Originally Posted by hellosailor

Jim-
Along Vasco's suspicions...RTFM first. Get that manual and make sure it isn't something terribly simple just set wrong. But I'd also emphasize, DO NOT PRESS TRANSMIT unless you know there is a working antenna on the radio. While most modern radios will protect themselves, some can easily burn out if you transmit without a working antenna connected to them. So if in doubt--keep it to one quick click, or don't transmit at all.
In a pinch, you should be able to take a wire coat hangar, a two foot long alligator clip (jumper wire), or other piece of wire and press it into the center hole of the antenna socket, and if the radio is working at all, it WILL receive something from strong local signals. If it still receives nothing, makes no noise?
The radio is set up wrong, or broken.

It can be something as simple as the internal connection to the internal speaker breaking loose. Or the transmit switch in the microphone being stuck. Or, the power lead to the radio may be corroded, chafed down to one strand, or a bad fuse. Sometimes there's one fuse in the power cord and another at the breaker panel "oops" so it helps to check the power cord, make sure the radio is getting proper voltage with enough power to at least light a test light or small cabin light bulb.

When all else fails...some marine electronics shops will still "take a look" for free.

Incidentally, for under $20 you should be able to get a "VHF emergency antenna" that comes in a plastic tube. Maybe a dozen feet of cable and a short antenna you can stick on the rail, etc. Makes a good way to test that your radio/antenna is good, even if you never use it for anything else.

Great advice. I will start from the beginning and check each step but am already leaning to me blowing the transceiver by attempting to transmit without antenna. This since the monitor screen is lit and shows the unit is working (channel changes and tx flashes when pressing the PTT).

I think I have enough information from members here to find out what is wrong - I will let you know what it is when/if I determine the problem.

Thanks again, Jim

[senormechanico]

Even in the unlikely event you fried the transmitter final stage by transmitting without an antenna, there's almost a 100% chance it would not affect sound output on receive.

[knottygurl]

sounds like its on hail, or like mine was, a cold solder joint at the speaker and a 5 second repair with a soldering iron and 30 mins of little finger playing to put it back together, those tiny screws are not for big fingers

[Jimske]

After some scrutiny checking various simple things I found the solution - bought another radio!

I took it to an electronics repair and the guy said it was a bad capacitor on a circuit board and showed me a white spot and said moisture caused the problem.

I didn't believe him and still don't but . . . only so much I can do!

The manual does say NOT to use the PTT more than a brief moment (as does the new radio manual) if the antennae is not working. I got to assume that I broke it myself. Breaking stuff is one of my specialties - sometimes expensive education!

Thanks again for all the help.

Jim

[fairbank56]

I don't believe him either. If he found the problem and he's a repair tech, why didn't he just fix it? I'm a marine electronics service tech with LOTS of VHF component level repair work under my belt. Transmitting without an antenna is extremely unlikely to cause a problem in the receiver other than possibly blowing the first receive RF amp. The white noise you hear when the squelch is turned off is "receiver noise" generated almost entirely from within the radio's receiver circuits, regardless of antenna status. The possible faults here are, bad speaker, bad solder joint, bad audio amplifier, faulty volume pot, faulty squelch pot. Anyway, good luck with your new radio.

Eric

[Jimske]

Originally Posted by fairbank56

I don't believe him either. If he found the problem and he's a repair tech, why didn't he just fix it? I'm a marine electronics service tech with LOTS of VHF component level repair work under my belt. Transmitting without an antenna is extremely unlikely to cause a problem in the receiver other than possibly blowing the first receive RF amp. The white noise you hear when the squelch is turned off is "receiver noise" generated almost entirely from within the radio's receiver circuits, regardless of antenna status. The possible faults here are, bad speaker, bad solder joint, bad audio amplifier, faulty volume pot, faulty squelch pot. Anyway, good luck with your new radio.

Eric

Yup. I will keep the old radio and when I bump into someone who can look at it I will still try and get it fixed.

In the meantime perhaps you can help with this: The new radio installed about 8 inches from breaker panel gets interference when the Nav Lights (and only the Nav Lights) are on. Do I have to move the radio to stop this or is there a way to prevent this? I'd like to keep the radio where it is but if I ahve to or it is easier to move it I will.

Jim

[fairbank56]

Are you using led type lights? This has become a very common problem with more folks using led fixtures. Disconnect the VHF antenna cable and move it away from the radio to determine if interference is being picked up by the antenna.

Eric

[Capt Phil]

Jimske, if you are mounting a new VHF unit and have or plan to install an autopilot at some stage, make sure you mount the VHF well away from the fluxgate compass location of the autopilot. The radio signal will play havoc with your autopilot operation if you don't. I've troubleshot several autopilot problems that had the root cause of ambient radio signals interfering with the autopilot performance... cheers, Capt Phil

[Jimske]

Originally Posted by fairbank56

Are you using led type lights? This has become a very common problem with more folks using led fixtures. Disconnect the VHF antenna cable and move it away from the radio to determine if interference is being picked up by the antenna.

Eric

Yes, I just changed all my lights to LED. Nav lights on top of mast still can cause interference? I will check it out. Cabin lights, too. Grrrr!

Jim

[fairbank56]

Originally Posted by Jimske

Nav lights on top of mast still can cause interference? I will check it out.

Yes, because the VHF antenna is so close to the fixture. LED's require a constant current source, so there is circuitry in the fixture and/or bulb to provide for this. There are many complaints about LED fixtures causing interference on VHF radio's.

Eric