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View Full Version : VHF radios and antenna - advice needed



jrj
10-26-2005, 06:14 PM
I would like to put a VHf radio on my boat. But, I know nothing about them. Can anyone provide any input on what is the best setup? I was at Eagle Lake this past week and discovered the need for one. Thanks in advance

norcalfishslayer
10-26-2005, 06:43 PM
I would like to put a VHf radio on my boat. But, I know nothing about them. Can anyone provide any input on what is the best setup? I was at Eagle Lake this past week and discovered the need for one. Thanks in advance

I just bought a small handheld unit. It seems to work great. I didn't have the room of a permanent unit in the boat. It dies 1 and 5 watts. The regular units do 1 and 25 watts.

From what I have read, the wattage helps, but what you really need is a loaded antenna. Look for a high gain antenna, that has a 6 or 9 DB gain on it. This will make a big difference in modulation.

I'm sure others have much more experience with VHF than myself, and I'm sure they will post here. Good luck.

frank

SuperDave
10-27-2005, 06:34 AM
How big is your boat? I spent money on a hand held and found out on a trip to Pyramid that I had to relay messages from boat to boat to get to my buddy on the other side of the lake. If you have room, 25 watt with 8' antenna. I bought a mini Raymarine 48 that has great volume, clear signal and takes up very little room at the helm.

cheesehead
10-27-2005, 06:47 AM
I too thought a hand held would be the ticket, but soon found out that I could shout farther.

VHF is line of sight, therfore the taller the antenna the longer you can reach out and talk with someone. (on the water that is).

I would not recommend the handheld.

good luck!

jrj
10-27-2005, 07:04 AM
Thanks for the response. I have a 19 ft Jetcraft boat. If the hand helds have limitations I will look into thefixed mount units.

SuperDave
10-27-2005, 07:05 AM
Anyone know how the patent is coming on those 8' belt mount antennas is coming? ;D ;D

Mickey_Thomas
10-27-2005, 07:07 AM
I'd say to ask Doc, but his hasn't worked right since before Pyramid Fest ;D ;D ;D Actually most of the 25 watt units put out the same, find one on sale. It's the antenna that's the important thing, buy the most expensive 8'er that you can afford. And don't use the soderless connectors, they are crappy ???

SuperDave
10-27-2005, 07:14 AM
With a 19' Jetcraft, Went might have antenna mounting issues. I sent him an e-mail to help him work it out.

drstressor
10-27-2005, 10:06 AM
Actually most of the 25 watt units put out the same, find one on sale. It's the antenna that's the important thing, buy the most expensive 8'er that you can afford. And don't use the soderless connectors, they are crappy

For once, I completely agree with Mickey. ;D

All of the permanently installed VHF radios work fine. The only difference is bells, whistles, and the degree of water resistance. Get the best 8' 6 db gain antenna that you can afford. 9 db antennas are only for sailboats and tall ships. Don't shorten the coaxial cable unless you really need to do so. Replacing the connector is a PITA.

cheesehead
10-27-2005, 10:25 AM
Don't shorten the coax?

Whats the reason there?

The instructions say cut to fit.

just curious... (cuz I cut mine :D)

drstressor
10-27-2005, 11:04 AM
You can shorten the coax within limits. The problem is just that replacing the connector is difficult. They really need to be soldered. The ones you crimp in place just don't work very well. Right now I can receive signal from a boat within about 1/4 mile, but I can't transmit at all. If I monkey with the connector, it works better, but only for a while. Many people have had similar results with solderless connectors. You have to be very careful how you crimp them since they break easily. And they only make contact with a small area of the ground/shield once they pierce the insulation.

Soldering those connectors is not too bad if you can do it at a bench. But in my case I had to thread the coax through a narrow opening in the deck that would not allow the connector to pass. So I added a solderless connector while laying on my back under the deck. Now it looks like I am going to have to solder the connector while laying on my back under the deck. >:(

The point is that I should have made the opening in the deck large enough to allow the stock connector to pass through and just coiled up the extra coax.

Jan_from_Humboldt
10-27-2005, 02:17 PM
You own a boat and you don't have one of these???
To own a boat is to also own lots and lots of neat gadgets ;D

Those solder coax connectors are a snap, just make sure you trim the insulation correctly. *
*
They sell them at Kragens

*

*
*
*
http://www.seenontvnow.com/images/coldheat.jpg

basil
10-27-2005, 03:07 PM
People think high gain antenna's are great, wrong. The problem with a high gain antenna is it's signal comes out in a narrower range. This is great if your boat stays straight up on the water, but on days when it's rocking your radio signal will be broken up to those recieving it.

Height is might in the antenna world so the taller you go the further you go. The fly in the ointment is that if the other guy has a short antenna then he will limit your ability to talk to him, but your higher antenna will help.

You don't really need to talk to the dark side of the moon, so just go get a cheap Shakespear antenna that is 8 foot. You can spend more but you won't get better reception. Shakespear antenna's get more expensive but have the same parts. They just make a connector a wee bit better and mainly they thicken the antenna body. This means it will take 15 lbs of pull to break it instead of 10lbs.

Also, if you go for the mount that swivels your antenna up and down, pass on the plastic one, they break. I find that it's better to just unscrew the antenna everytime and unhook from the radio. Then it doesn't hit any trees going out of your driveway or get stepped on if you fold it down in the boat.

cheesehead
10-27-2005, 03:24 PM
good stuff Basil,
I agree, I paid $50 for a Shakespear 8', and a friend of mine paid over $100 for a 4' *(Hi Doug). *

The coax I got with mine was connected to the antenna but the other end was loose, I cut it to fit, thread it through where I needed it and attached the connector. *

The stainless mount is the way to go too. Pricey, but hey I'm rich!

I couldn't be happier with the set up now...(albeit, it is the 2nd time around) * * * *

drstressor
10-27-2005, 03:28 PM
Jan_from_Humboldt, you're the second person to recommend one of those gadgets. Gotta get on for soldering while laying on my back. :)

Mickey_Thomas
10-27-2005, 03:39 PM
I disagree with getting the cheap 8' antenna, that's the one I put on my old boat, they don't put as clear a sound and break easier. My advice would be to go to West Marine and compare how they are made, the best one will be about 189.00 and they are worth it. Ask GoneFishin or Hammer, you can hear the difference. ;) With all that money Cheesehead you should have sprung for the best ;D

drstressor
10-27-2005, 03:41 PM
There really is a difference in sound quality with the better antennas. No difference in range though.

Mickey_Thomas
10-27-2005, 04:34 PM
All you have to do is listen to Ron's radio on Pyramid and you can hear the difference, does that make twice in one day that Doc agreed with me? I'm so honored ;D ;D ;D

cheesehead
10-27-2005, 05:02 PM
Micky,
I agree. :D
Cheese

Jan_from_Humboldt
10-28-2005, 02:13 PM
Jan_from_Humboldt, you're the second person to recommend one of those gadgets. Gotta get on for soldering while laying on my back. :)


Two things to remember when soldering under the console on your back.

Safety glasses and make sure you keep your mouth shut while soldering. ;D

drstressor
10-29-2005, 05:54 PM
So I went out and picked up one of those Cold Heat devices. Absolute pieces of "As Seen on TV" junk! Probably $3 worth of materials at most. The batteries that came with the unit didn't produce enough heat to melt the solder. With new batteries I could only melt the solder in intermittent blobs. Can't do any precision work at all. It's going back to Home Depot. >:(

fish4fun
10-29-2005, 11:24 PM
Doc I've been thinking of getting one of those "cold" soldering devices for a while. The trouble you had will probably scare me off. To get a good solder joint you don't just have to melt the solder, you also have to raise the temp of both things your soldering together so that they are hot enough to melt solder. When this happens the solder flows because it "wets" the surface of the two things being soldered together. If you can't get everything hot enough, you get what's called a "cold" solder joint. Cold solder joints are structually weak and can crack or break open due to physical stress or vibrations.

Sometimes it takes a lot of heat to raise the temp of the things being soldered to a high temp. If the solder gun doesn't have enough heat capacity to overcome the thermal mass of what's being soldered, it won't work. It might melt solder but it won't solder everything together properly. It sounds like the "cold" solder gun you bought might melt thin pieces of solder to a small pad on a circuit board(low thermal mass). It might not have enough heat capacity to melt thicker pieces of solder and it's very unlikely to have enough heat capacity to raise the temp of the coax connector and the ground shield wire to a high enough temp. Don't think I'll buy one. I'll stick with the soldering irons I've got.. Larry