VHF Radio no Tx?

[dpslusser]

Hey guys, im kinda new to VHF radios, but have some CB experience. My buddy gave me a VHF radio for my new boat and an antenna. For some reason I can't Transmitt very well. Not even to a boat that is 100 feet a way. Recieveing, is GREAT. I was wondering, like CB, doe s vhf antenna have to be trimmed for SWR?

 

[QC]

Re: VHF Radio no Tx?

You should repost in Electronics vvvvvvvv

 

[DRIFTER_016]

Re: VHF Radio no Tx?

No they don't need to be trimmed like CB antennas.
Try a different antenna as yours could be fubar.
If a new antenna doesn't fix the problem it's an issue with the radio.

 

[dpslusser]

Re: VHF Radio no Tx?

My grandfather (who was in the Navy and has been fishing for 20 years) is the one who put the antenna on the boat. He SWEARS that the antenna has NOTHING to do with it. Although I HIGHLY HIGHLY HIGHLY disagree. The antenna is the most important part of the entire radio rig. But... he is the type you can't tell him anything. After inspecting the antenna/cable/connector, the antenna actually has a crushed section about 2 inch's long. (I don't no how to upload picture to post). I even showed it to him. He says its STILL THE RADIO!!!! And the connector looks shoty.

Am I rite? Is the antenna the main most important part of the Radio rig? Its the same way in CB (for the most part). Without a GOOOOOOD antenna, your almost wasting your time.

 

[bruceb58]

Re: VHF Radio no Tx?

Try being further away than 100 ft and/or try transmitting at a lower power...often there is a 1W setting. You might be saturating the receiver of the other radio.

 

[dpslusser]

Re: VHF Radio no Tx?

Try being further away than 100 ft and/or try transmitting at a lower power...often there is a 1W setting. You might be saturating the receiver of the other radio.

I couldn't talk to anyone, even other guys far out on the lake. My Grandfather had his boat and we tried it that close (100ft)

 

[Expidia]

Re: VHF Radio no Tx?

Go pick up a 4 foot or a base loaded small antenna at West or Walmart to swap it out with. You can always return it. If the antenna has a bare ended wire. . . most antennas need a connector to be soldered on after you fish the wire through.

But I bought a crimp on connector for $10 at West Marine.

Save all the packaging. Don't crimp the connector to tight, so you can remove it after if you are going to return it later.

If it works you might end up keeping the antenna anyway or swapping it for a taller one. An 8footer will give you maximum range.

If it still doesn't work, then you know it's the output part of the radio. A radio can be pretty cheap to replace if money is an issue. I've seen close outs online as low as $39.

Or trailer boat to a marine shop and they can check it with an SWR meter.

SWR meters start at $50 and up. Seems a waste for the one time use.
But you could buy one of those and return it too after checking the output out. It hooks up between the VHF and the Antenna.

But I'd try the buying a cheap antenna first, seems like the easiest solution to me.

 

[watermellonI]

Re: VHF Radio no Tx?

Hey Slusser
I think the crushed wire is your problem, you will need a new antenna and wire.

 

[watermellonI]

Re: VHF Radio no Tx?

Hey Slusser
I think the crushed wire is your problem, you will need a new wire.

 

[dpslusser]

Re: VHF Radio no Tx?

the antenna was the part that was crushed. Fiber glass. But I don't understand is, how was it still able to recieve VERY well, but not transmitt?

 

[Boatist]

Re: VHF Radio no Tx?

If the Coax or the connector or the antenna is shorted then the Standing wave will be greater than 3 to 1. With a standing wave 3 to 1 or higher the transmater will shut down to protect it self and will not transmit.

Where I go to the ocean I carry a SWR metter and 30 feet of extra Coax and a PL258. Over the years I made a lot of friends where we camp. Many have had radio that would either not here many stations or not be able to reach station near by. It all started when one friend was fishing along side in the ocean and he could here my radio all the time but nothing on his.

After cleaning all the fish he came over and ask what kind of radio I had and explained how many more station I picked up than him. I went over to his boat and checked and sure enough his standwave ratio was off the scale. I had him pull his boat over near mine and put the extra cable from his Radio to My antenna and checked again. Now check about 1.7 to 1 and his radio came to life.

I done this for many years and at least one every other year and in all that time only had two problems be with the Radio. One the speaker in the radio was bad but if plug in and external speaker it work great. The other would not transmit but would recieve very good. This one was because they wired the radio straight to the battery with light wire like 18 guage. When you would transmit 25 watts it was clear it had a power problem and the light and the LCD would go very dim. Put it in 1 watt mode and it worked very well. Next day he got some 12 guage wire and we changed and that solved the problem.

Every other problem over 28 years has been the coax or antenna. Most often the PL259 they used too much heat and the center coax was shorted to the brade. Another common problem was they drilled a hold thru the deck with no protection and the coax got cut and was shorted or full of water.
Lots of the small flexable antenna use tuned coax as a radiator and over time that will break down inside the antenna.
Anyway the point is 90 percent of the time it was coax or Pl259 shorted or the wire inside the antenna was bad. One more that I seen several times was the coax was bad where it bends when they lay down the antenna as they had the wire way too tight forceing it to bend right where it go into the antenna.

If you know a Ham on the VHF Band they will likely has a SWR meter and can check it for you. Most CB SWR meters will not work in the VHF band.
Good LUCK maybe your could give him an antenna for farther day.

 

[dpslusser]

Re: VHF Radio no Tx?

I swapped out the antenna, and put a new connector on it. Unfortunetly I have no way of testing it since I have it back home, and there no water (VHF chatter) in my area. I wouldn't pick anyone else up unless they were on a lake or ocean rite? Whats the point of sitting there in scan mode waiting for someone to key up.

Is there anyway to test it with a frequency scanner (police scanner)? Will a scanner pick up vhf frequencies?

On a key note- I noticed with the new antenna and/wire/connector, the squelch doesn't have to be set as high. Before the squelch had to be turn clockwise almost 2/3 the ways before it shut up. Now I can turn it 1/4 inch clockwise and it shuts up. IS THAT A GOOD THING?

 

[Boatist]

Re: VHF Radio no Tx?

I do not know where your live but most radios will have weather channels that brocast 24 hour a day. I forget but thank there are 8 weather channels and most parts of the country have at least one channel you could pick up. Many areas will have 3 or 4 you could pick up. Give them a try.

IF the antenna is picking up more back ground noise then you would normaly have to set Higher to silence the radio, so I do not think that is a good thing.

If you try scanning try 16, 22, 68, 69, 83.

 

[waterinthefuel]

Re: VHF Radio no Tx?

You'll need to scan in the 154-157 mhz band. Channel 16 is 156.800mhz.

You have the right idea. Always get a new antenna, that way you can isolate everything behind the radio. Pretty much only leaves the radio as suspect with a new antenna. That way if it is the radio you'll only need a radio, as you're sporting a nice shiny new antenna already.

You can receive radio signals through a wire if you know what you're doing. It takes a lot more to transmit than to receive. Think about it, a scanner antenna can receive beautifully, but try to transmit with it and you'll cook the radio. It's not tuned correctly. But a marine VHF antenna does NOT need to be tuned for SWR. It already is.