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Bugsy
11-02-2008, 04:27 PM
I have a Shakespeare antenna with extension. To remove it from the boat to paint, I had to cut the RG58 cable. I noted that this cable is old and the exterior sheath is brittle so-----I'd like to replace the cable.

I've now learned that the extension is the stretch which I thought was the base and vice versa--the base is the whip end. It appears that the cable runs through the extension but is soldered within the base.

Is my impression correct? Does this mean my only options are 1) buy a new antenna or, 2) "butt connect" new cable to the existing cable and hope for the best?

Thanks for any guidance.

TedZ
11-02-2008, 05:22 PM
Little confused but i'll try.

Butt splicing with the gold plated RG58 connectors is not the best but it will work ok. The condition of the coating of the wire inside the antenna does not affect the performance...obviously outside of the antenna you do not want shorts to the shield by the center conductor. If the shield shorts to ground that is ok.

Does this help??

Ted

Bugsy
11-02-2008, 05:30 PM
Thanks, Ted. I think I understand. Of course I hoped that there would be a "magic bullet" with a connection within the antenna that one could access once given the "secret".

The cable is brittle and the shield exposed VERY close to the antenna housing ---only inches (two?) from the little grommet through which the cable passes going into the stainless part of the antenna. Because of my fear of moisture intrusion, I was hoping to replace that portion of the cable which I won't be able to do if I need "connectors".

REBrueckner
11-02-2008, 06:14 PM
No, those are not your only options:

Unscrew the upper whip from the lower extension....

I replaced a similar worn and brittle cable in a Shakespeare antenna extension several years ago...It took a few minutes to figure out the innards, but I was able to replace the entire cable ,,,I even got the innards out of the top whip and replaced the cable up inside the whip as well...I do not remember the details, but I do remember it appeared more confusing at first look than it turned out to be...a pleasant surprise on a boat project!!!....

There was also a bit of moisture I found in there, I think from the extension to upper whip thread type fastening....so I put some caulk on the threads and butt joint before reattaching the two.

All the "transmitting and receiving" stuff in the whip should pull down with the connecting coax cable...they are pushed up inside and soft styrofoam cushion is the only thing holding them in place....

jim rosenthal
11-02-2008, 08:30 PM
Have you asked Shakespeare about this? Sure, they will try to sell you a new one, but someone soldered that into place on the assembly line, and you should be able to unsolder it and put in a new piece of cable. The Ancor antenna cable is very well-made, by the way.

Bugsy
11-02-2008, 09:20 PM
No, those are not your only options:

Unscrew the upper whip from the lower extension....

I replaced a similar worn and brittle cable in a Shakespeare antenna extension several years ago...It took a few minutes to figure out the innards, but I was able to replace the entire cable ,,,I even got the innards out of the top whip and replaced the cable up inside the whip as well...I do not remember the details, but I do remember it appeared more confusing at first look than it turned out to be...a pleasant surprise on a boat project!!!....

There was also a bit of moisture I found in there, I think from the extension to upper whip thread type fastening....so I put some caulk on the threads and butt joint before reattaching the two.

All the "transmitting and receiving" stuff in the whip should pull down with the connecting coax cable...they are pushed up inside and soft styrofoam cushion is the only thing holding them in place....

You know--I went in to a local marine supply store this pm and they pulled out an antenna for me. I didn't think of anything at the time---the innards (so to speak) looked just like mine and so I concluded (aided by the clerk's comments to the same effect) that the interior cable couldn't be accessed. BUT-----I remember the bit of styrofoam that was visible within the antenna in the store. And now---I have renewed hope.

I'll take my antenna to a local "communications" company and see what they have to say.

I respect the "naysayers" ---but I cherish the hope presented by Mr.Brueckner.

Boatsb
11-03-2008, 07:56 AM
It would be best to replace the antenna. The wire in it has aged and could be weak and may fail. This is one of the places that saving a few dollars could bite you hard. If it fails and you need it you will regret repairing it. A new antenna is less than $100.00 Hardly worth the time and effort to have a repaired antenna as a lifeline.

Capt K
11-03-2008, 08:11 AM
If yours are just an 8' whip on top of an extension, buy the new whip. You will save a ton of time and aggravation, and the cost would be about the same by the time you finished fooling around with the old one.

If you have the large db gain 14' antennas like I have, they cost over $400 each, so it would be worth checking out your options.


Good luck!

K

Bugsy
11-03-2008, 09:00 AM
Yes. I have the 15 (+/-) ft. extension plus normal base and my searches suggest replacement with like kind would run around $400.

However, since the coaxial threads through the extension, one could just purchase the replacement base but you'd still have to splice the coaxial since I'll need something like 40' of cable.

Research indicates that both Comrod and Digital have eliminated this issue so you can simply "screw" in a new cable to the base of the antenna.

However---that still requires a significant cash outlay.

Trojan
11-03-2008, 03:38 PM
It depends on how the antenna and cable was inserted into the glass tube and whether its a quarter, half wave or a five eights wave antenna. You could use a PL259 and a barrel connection onto another PL259 and let the splice hang in the lower section. If you seal it well there will be minimal signal loss. Since the splice is so close to the antenna. Your RG58 is real lossey. Anytime you splice a cable you create an impedance bump in the line. You can also use the super X RG8 which is the same dia. as RG58, but half the signal loss as RG58. The quarter wave is just held inside the tube with a string at the top and can be carefully removed. Add a new string and feed, pull the repaired antenna back up inside. The longer antennas are a little harder to repair.

BILL

Bugsy
11-03-2008, 04:03 PM
I think the problem in part is that I don't know what model antenna I have. It is old (hence my need to paint over the fraying glass) and is probably not far from original to my 1981 43C.

I spoke to a local company which suggested: 1) cut the antenna near the threaded base. 2) use the 3" of unweathered cable thereby exposed and install a mini-connector; 3) clean out the base and re-glue the shortened antenna into the base; 4) attach replacement cable to mini-connector and run to radio.

I then spoke to Shakespeare tech support. I was told: 1) the extension is an antenna and its function may be impaired by cutting off any portion; 2) there is a "little" slack of cable within the antenna. If sufficient, pull it out (carefully) and make the connection to the replacement cable; 3) each connection results in a loss of 1/2 watt and a butt connection equals two connections--a 1 watt loss. He then said something to the effect that the increased db on the longer antennas accomodates the likelihood of at least one connection for longer cable runs. He said I might be able to remove the internal workings to splice in a new cable but I would need a "wave meter" (?) to restore it to its original position. Forget that!!

Trojan...I don't know whether my antenna is 1/4, 1/2 or 5/8th wave. I confess that I don't understand your suggestion to splice using two PL259 connectors "hanging" inside the antenna body. I was of the impression that the cable just ran through the 5 ft. "extension" but Shakespeare says "No" and; "This isn't just an extender to raise the height of the base. This is a two-part antenna."

Boy! It never ends, does it? My wife is struggling to reconcile conflicting info as to the minimum temp at which Awlgrip can safely be applied (she took our meat thermometer to measure the surface temp!!) and I'm whiling away the hours trying to rehabilitate an antenna.

Bugsy
03-10-2009, 08:38 PM
As recommended, I ordered the low-loss RG213 Shakespeare cable for my VHF. It is SIGNIFICANTLY larger than the cable within the antenna from which I've extracted about 6"-8" which I intend to "splice" to the new cable using (as recommended here) the PL259 connectors with a barrel connector increasing from what I presume is the original RG58. I'm hoping I'll have enough original cable so that it won't be necessary to increase the size of the hole in the hull through which the cable passes.

Question(s); 1) there is a connector to connect the RG58 to the RG213, isn't there?
2) please confirm that I will be able to purchase a "plug" that will go on the RG213 and connect to my VHF. I'm having trouble visualizing this because obviously, the existing "plug" is at the end of cable which is 1/2 the size of the RG213.

There will be no additional "splices" and I will only cut as much cable as required to make the run to the radio in the bridge overhead.

Thanks for the guidance.

Boatsb
03-10-2009, 09:47 PM
There are Pl-259 connectors made for RG213. or you can buy an extension already made but I have to question why not replace the antenna and have a known quantity. Also the total length of the cable is a multiple of the wavelength so just adding is not always better.

FYI the 23 foot 9 DB gain antenna new is around $300.00 Thats the big bad unit that is great for offshore. Way offshore. 6 DB 8 foot units are lots less than $200.00 For the cost of the new cable and the time to fix it up you can probably replace it and have enough left over for a sixpack.

PM me if you need the connectors. I know where to get them.

Trojan
03-11-2009, 12:08 PM
I'm not sure what antenna you have ether. But if the cable in the lower section is just coax. It is not part of the antenna. Without seeing the antenna I can only guess. I don't remember any of the compound antennas that use the short base as part of the antenna. If the antenna itself is removable from the whip base. Then you can unsolder the old coax and re due with new. The antenna is pulled into the fiberglass tube by a string from the tip glued at the tip and cut off. The foam is just to keep the assembly from rattling inside the tube. The antennas are almost all of the J-pole configuration. Very simple antenna. This includes the high DB gain antennas. The expense changes is in the build material. Coax verses brass. It's an easy repair if you can solder. Only rosin core solder is to be used. Use good coax no radio shack crap. You can not but splice coax. Use a pl259/barrel/pl259 with reducers for cable size. I use liquid tape to seal it all. If you just change the feed coax you will not need an SWR bridge. You have not changed the wave length of the antenna. Where are you located. If Fl. maybe I could help. I'm in Naples now.

Bill

Bugsy
03-13-2009, 11:13 AM
Bill...

Thank you VERY much for the offer. Although I'm currently in Fl., the boat is now in storage up north awaiting Spring launch.
I'm pretty sure that I've managed to complicate a simple chore. As suggested by boatsb, perhaps I should just have bought a new antenna but I thought; "Why pay $350 when all I have to do is paint this one?" and so it began and, of course, I'm now "into it" having purchased the RG213 to replace the existing cable 6" of which was brittle because of exposure to the elements.

I've copied your remarks and will try to find someone as helpful up north to guide me through the process.

Thanks again.

Trojan
03-14-2009, 12:36 AM
You should be in good shape. I think Boat US has the PL259, barrels and the reducers. Don't use Radio Scrap. The first thing to do is slide the PL259 barrel nut on the cable along with the reducer. Then trim the cable. Cut one inch of the outer insulation off with a sharp knife. Don't nick the braid. Then you slide the reducer on down. Fold the braid back over the reducer and hold. Trim the braid so the braid does not cover the threads on the reducer. Trim the center foam to about 1/8 from the reducer leaving the center wire sticking out. Don't nick the center wire. Screw the reducer into the PL259 tight. Do not pull on the cable at this time. Solder the center wire protruding from the end of the center. Let cool. Then through the holes in the PL259 solder the braid 4 places. Let cool, screw the barrel nut on to the PL259 and your dune. Watch the heat, you can melt the center of the PL259. Don't use a torch and don't get carried away with the solder. Good luck
Thats OK. I left Daytona last Thursday for Naples. I'm now in Cape Corral and Fort. Myers. I will be in Immokalee next Monday and maybe back in Michigan for the weekend. Time to get the boat ready for an Easter launch. Was going to the Keys, but changed MY mind:D
BILL