VHF Radio Troubleshooting

[oreana123]

I have an older marine radio I'd like to use. After installation, I tested the radio with another handheld that I know is working. The radio in the boat does not RX. It does TX quite nicely. I changed antenna from a known working VHF radio, and still no RX! TX is the same: good. Anyone have another idea? I guess that this problem is internal to the radio, but I am willing to try anything. Since it TX's fine, I know that it is getting a good power feed. I have tried on multiple marine frequencies as well. Pitch it over the side? John S

 

[Ed13944]

Try this

First, I would check the volume and squelch controls. If the squelch is set too high, you won't receive anything. There may be other settings for tone squelch, etc, which can be shut off. If there is a "monitor" button, push it and hear the static. If this doesn't work, check the speaker. Plug another speaker or earphone into the jack, if it has one. It is possible the speaker is blown or rotted. New speakers are cheap. NOW, if nothing has worked, toss it.

 

[oreana123]

VHF RX

Thanks for the hints. The squelch and the speaker works perfectly. After a long life of RX'ing, I think a printed circuit component is fried, so I'll disassemble the radio and learn on it. Ebay has some nice new radios-I'll just get me one. John S

 

[Ed13944]

OK

Oriana, I don't want to sound like a wiseacre, but how do you know the squelch and speaker work if you can't receive? Your decision, though, is probably a good one. Good VHF radios are available for reasonable prices, even new. I seem to have a collection of them, 3 handhelds and 2 12V units. All different, but they work. Right now I am deciding what to do with my Loran C.73's

 

[oreana123]

T/S VHF Radio

Nah,I dont think you are a wiseacre at all! If I turn the squelch adjustment to the most sensitive end, I get the squelch noise over the speaker. So the speaker and the squelch systems both work. But for some reason the radio will not receive a signal from either of my 2 meter radios, although both of those radios can receive voice transmissions from the marine radio in my boat. Speaking of Loran, I have a system as well. I am researching how to use the system. Does the Screen, which I have not powered up yet, give you cordinates of Lat/Long? What will it show me?In aviation, there is a system not unlike Loran in that it has been bypassed by technological developments, but it is still there. MLS was to be the precision landing system of the future. Lots of our tax dollars were spent on it and continue to be spent on the MLS system. It is very good at what it does, but only a few airports have MLS Landing Systems and outfitting an aircraft for it and training the personnel is expensive to say the least.

 

[Ed13944]

Loran C

Interesting radio problem. Might be something as simple as a switch contact. Could be a little electrical spray, or wd40, in the switch would clear it up.Re: Loran C, this system does read out Lat/Long and was pretty good in its time. But now it is scheduled for destruction and will wink off about 2008. It has been replaced by GPS. I think I will just remove it and the antenna and put in a nice CD/Stereo unit.

 

[John S]

Loran C

I spent a half hour last night reading the info on the US Coast Gaurd site about Loran C. Pretty tedious.Written in the early 90's, it makes predictions that never came true. Points out weaknesses and deficiencies in the GPS system that never came true. So they plan to pull the plug on the system. Well, there are those who say that we should not rely on a "single source" of naigation info, but for those who are really worried, sharpen up those sextant skills. I read an article on Sailnet about a guy who bought an old Rnav unit from the used store. Next he will be finding an old Loran C unit. John S

 

[Ed13944]

Right on!

Basic nav skills are so important. I just took the coastal nav course, and found it very useful. Before, I was just looking at my charts and following the GPS. Now, I use several techniques, marking each fix on the chart, cross-checking as I go. GPS is still a tool, but only one of many. That way, if the GPS goes down, I can still find my way home.I have a sextant, but don't need to use it with the kind of sailing I do. Never mastered the technique of measuring degrees from horizon accurately while my boat is rocking. On a calm sea, no problem, so long as you brought the right book.Yesterday, I was in a plane and the pilot said he was on a great circle route. I actually understood what he was talking about, for a change.

 

[ronbuckles]

Noise but no signal...

Receivers are made up of two parts. The front end, which is used to select the frequency and convert the incomming signal (RF, or radio freqency) to a lower freqency to be amplified. The other part of the receiver is a series of low frequency amplifiers that boost the signal from tiny to something useable. The lower frequency is called the IF, or intermediate frequency.Any time you hear the noise when the squelch contorl is turned off means the amplifier (IF) part of the radio is working and the the front end is the problem. This could be a whole host of things. If you can not even punch thru with a radio transmitting right next to it, then it probable not the antenna and the front end is dead! Probably time for a new radio.The features on the new ones are wonderful. They almost do it all for you.Ron