how to make the antenna connection?

[littledevil]

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Hi. The coax cable (RG58) was damaged so i have removed it from the mast and i am getting a new cable. I am wondering if anyone can tell me how i am going to attact the new coax cable to the antenna. I believe its sheakspeare, about 5 feet tall. Seems to be in decent condition and if can hook up the new cable i should be all set. There is a little bracket on the mast head, using the nut( it is shown in the picture in my palm) it securely sits on the top of the mast. i wasn't able to remove the metal part at he bottom of the antenna. The antenna is fiberglass,

[fallingeggs]

Hello fellow New Yorker. It's a bit cold these last few days to be messing around in the yard, eh? You won't see me back out there till March.

Here is a guess at what I'm looking at. The coax to your antenna is integrated into the antenna at the ferrule (the bottom metal part of the antenna). I doubt you can remove the ferrule to replace the coax's connection at the antenna end. You could splice in a connection just down from the antenna, but you'll be left with some old coax.

If this is the case, you might be buying a new antenna, one where the cable can be removed from the antenna at the ferrule so it can be independently replaced. Antennas can be cheap and if you're staying on the Hudson, anything will do.

As an aside, I'd suggest taking a quick read through the below site regarding installing coax cable install. Has some useful info if you plan to install the connectors yourself / general knowledge.

Easy VHF Connections Photo Gallery by Compass Marine How To at pbase.com

[littledevil]

Originally Posted by fallingeggs

Hello fellow New Yorker. It's a bit cold these last few days to be messing around in the yard, eh? You won't see me back out there till March.

Here is a guess at what I'm looking at. The coax to your antenna is integrated into the antenna at the ferrule (the bottom metal part of the antenna). I doubt you can remove the ferrule to replace the coax's connection at the antenna end. You could splice in a connection just down from the antenna, but you'll be left with some old coax.

If this is the case, you might be buying a new antenna, one where the cable can be removed from the antenna at the ferrule so it can be independently replaced. Antennas can be cheap and if you're staying on the Hudson, anything will do.

As an aside, I'd suggest taking a quick read through the below site regarding installing coax cable install. Has some useful info if you plan to install the connectors yourself / general knowledge.

Easy VHF Connections Photo Gallery by Compass Marine How To at pbase.com

Hi. Yes very cold indeed. I finally decided to step out and continue with the project today. Not much progress though. Your guess seems right, i will try to manhandle the ferrule and see what is going on inside. if it breaks, oh well nothing to loose. Most likely i will get an antenna as you suggested but still wanna give it a shot. Thanks

[capt jgw]

On a lot of cheaper antennae the center conductor of the coax runs all the way to the top and is the working part of the system. No way to remove it. You can cut it off and add a splice, but then you've added a failure point. Better to replace the antenna with one with a removable cable.

[Pete7]

Agreed you would probably better off replacing the lot. However, before you rush off down the chandlers, please have a read of this thread and then buy a good quality antenna and cable rather than the normal cheap stuff in a chandlers.

http://www.cruisersforum.com/forums/...nna-99651.html

Pete

[Goudurix]

Originally Posted by capt jgw

On a lot of cheaper antennae the center conductor of the coax runs all the way to the top and is the working part of the system. No way to remove it. You can cut it off and add a splice, but then you've added a failure point. Better to replace the antenna with one with a removable cable.

The above is right. You will either find that or some kind of narrow print board. Electronically these type of fiberglass encased VHF antennas are either J-pole type or 1/2 dipole type.
I would not try to open it. I would connect a PL259 plug on short tail of the orignial coax which looks like RG-58 size. The downside of this is you will probaly do that at the top of the mast if you need to fix the metal base of the antenna on it's support.....I have done that but if you're not familiar or experienced in soldering up a PL259....not an easy task up there.
If you want to "save" that original antenna by all means, I would unmount the antenna support from the mast (bolted? popnails?), and fix the antenna in the mount at "sea" level, and install the PL259 there. Then take that up and just reinstall the antenna support with the antenna. Take advantage of the situation to replace the usually cheapish RG58 antenna coax by a better quality and lower losses (RG-8 or RG-213 or Airecell7) - you will get nearly double the power reaching the antenna than today for your typical 10-14m mast.... in that case mount a PL259 to the top end of the coax cable, then elad down the other end from the top of the mast using the old cable or suitable rope as pulling cable. Connect both PL-259 togethher using a UHF PL258-G barrel connector. Seal well with self-amalgating tape. Protect this with electric tape. Fix the connection somewhere near the antenna base with tie-wraps or similar.

Another alternative (my prefered one) would be as suggested to install a brand new high quality VHF antenna with PL259 socket, and repair the old one as suggested above, and keep it as a spare VHF antenna that you can install in an emergency on the pulpit.

Jan

[Adelie]

You should probably get a shorter antenna. The longer antenna gets you more gain which means better reception when the boat is not heeled. The more you heel the more reception will fall off though for transmitters to port or startboard. Transmitters ahead and behind will not be as affected.

If you had a powerboat, the bigger antenna would be great. For a sailboat you should mount a 3db antenna. A 3db antenna for marine VHF is about 3' long which is about 1/2 the wave length.

[Goudurix]

Originally Posted by Adelie

You should probably get a shorter antenna. The longer antenna gets you more gain which means better reception when the boat is not heeled. The more you heel the more reception will fall off though for transmitters to port or startboard. Transmitters ahead and behind will not be as affected.

If you had a powerboat, the bigger antenna would be great. For a sailboat you should mount a 3db antenna. A 3db antenna for marine VHF is about 3' long which is about 1/2 the wave length.

When stepping down the mast the similar fibreglass encased antenna was broken of. I replaced it with 1/2 wave S/S whip antenna from Glomex. Sturdy, flexible, and has a connection at the base of the antenna for PL259 UHF plug. Glomex (Italian) is maybe not the same quality as Shakespeare, but it has been reliable and maintenance free since many years. I took advantage of running a better lower loss coax and often hear but can also talk to Dover port control from the belgian coast line (> 60 NM). Which tells me the antenna system (antenna + feedline) is working well.