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jkidd
Joined: 23 Oct 2006
Posts: 1616
City/Region: Northern, Utah
State or Province: UT
C-Dory Year: 2007
C-Dory Model: 22 Cruiser
Vessel Name: Voyager
Photos: Voyager (JK)
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 Posted: Wed Apr 03, 2024 11:27 pm Post subject: |
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Well I will try to explain my thoughts. Shakespeare 8' low end is $115 and Mid range is $190 they have 2 flaws. 1 the fiberglass tube will get brittle in the sun and break off. 2 where the coax goes into the base of the antenna the sun likes to rot the cable right there and then it will let in water or short. They also have a $330 8' that takes care of both of these problems. The reason I say there OK is there going to work for a while before you have problems and then you just replace them, but you will probably find the problem when your boating and can't fix it right away. The Morad is $225 and $35 for a cable and $45 for an adapter. It is 4-1/2' long made with an aluminum tube and a Heavy Stainless Rod and Nylon caps. It is going to last a whole lot longer than the fiberglass antennas.
All of these have 6db gain. If the cable goes bad you can just put another one on. So in the long run I think the Morad is cheaper. The Morad is tested before it leaves the factory and meets these specs Nominally 1.15: 1 @ 156 MHz (center freq.). 100 Watts max. / 50 Ohms. 100 mph. Every thing is a compromise if you compromise on the antenna you lose distance. If you need to talk 5 miles then probably anything is going to work. If you need maximum distanced then don't go cheap on the antenna.
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Jody Kidd
KE7WNG
Northern, Utah
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colbysmith
Joined: 02 Oct 2011
Posts: 4551
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
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| Posted: Thu Apr 04, 2024 11:54 am Post subject: |
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| jkidd wrote: | Well I will try to explain my thoughts. Shakespeare 8' low end is $115 and Mid range is $190 they have 2 flaws. 1 the fiberglass tube will get brittle in the sun and break off. 2 where the coax goes into the base of the antenna the sun likes to rot the cable right there and then it will let in water or short. They also have a $330 8' that takes care of both of these problems. The reason I say there OK is there going to work for a while before you have problems and then you just replace them, but you will probably find the problem when your boating and can't fix it right away. The Morad is $225 and $35 for a cable and $45 for an adapter. It is 4-1/2' long made with an aluminum tube and a Heavy Stainless Rod and Nylon caps. It is going to last a whole lot longer than the fiberglass antennas.
All of these have 6db gain. If the cable goes bad you can just put another one on. So in the long run I think the Morad is cheaper. The Morad is tested before it leaves the factory and meets these specs Nominally 1.15: 1 @ 156 MHz (center freq.). 100 Watts max. / 50 Ohms. 100 mph. Every thing is a compromise if you compromise on the antenna you lose distance. If you need to talk 5 miles then probably anything is going to work. If you need maximum distanced then don't go cheap on the antenna. |
I don't necessarily disagree with what Jody is saying. I usually don't have to replace my antennas until I hit something with them, and then they break.  Perhaps they wouldn't last much longer than 5 years anyway...which seems to be my "breaking point"... The Morads do have a good reputation. However, I would need to get extenders to get them as high as my current antennas, and height does count! I know from tearing the Shakespear apart, that there is really only about 2' of antenna anyway, and that is taped into the top of the fiberglass whip. I've been pretty happy with my main radio, a SH GX2150 I believe, and that is hooked up to my port antenna. I've replaced the starboard antenna, it's cable, and that radio (currently with the SH GX1600 I believe.) That secondary radio shares the starboard antenna with my AIS transceiver, through an antenna splitter. However, I have also tried hooking that radio up to my port antenna, with no improvement in distance. So I'm once again inclined to believe that I just have a very good GX2150. Both antennas check out within specs on my SWR meter. I do seem to hear from a farther distance than many others, but there are others that can hear farther than me. In the end, I'm satisfied with at least my GX 2150 performance. Colby |
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thataway
Joined: 02 Nov 2003
Posts: 20814
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
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| Posted: Sat Apr 06, 2024 1:28 pm Post subject: |
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At times I have taken some of my antenna test gear to check out antennas at West Marine. I found a number were not up to specs--sure they worked, but not optimal. I don't know what testing that "Shakespeare" or "Digital" do but some antennas do slip through that are not optimal. The antenna design is the first issue, then the quality of parts used, and finally the antenna lead and its fittings (the PL 259 which connects to the radio and the quality of the connection.). I can easily cut a coat hanger which will function as an antenna--you can listen and transmit fairly well. But that is not optimal. Jody also brought out the exact location, with magnetic fields, man made interference, and physical blockade to start with.
I put in a graph of Amateur 2 meter antennas,, because I could not conveniently find any marine VHF (Frequency is slightly higher. But you can see variations of the SWR curve, some being not quite as good)
_________________
Bob Austin
Thataway
Thataway (Ex Seaweed) 2007 25 C Dory May 2018 to Oct. 2021
Thisaway 2006 22' CDory November 2011 to May 2018
Caracal 18 140 Suzuki 2007 to present
Thataway TomCat 255 150 Suzukis June 2006 thru August 2011
C Pelican; 1992, 22 Cruiser, 2002 thru 2006
Frequent Sea; 2003 C D 25, 2007 thru 2009
KA6PKB
Home port: Pensacola FL |
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ssobol
Joined: 27 Oct 2012
Posts: 3374
City/Region: SW Michigan
State or Province: MI
C-Dory Year: 2008
C-Dory Model: 22 Cruiser
Vessel Name: SoBELLE
Photos: SoBelle
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| Posted: Sun Apr 07, 2024 9:33 am Post subject: |
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Just want to say something about the strength of the Shakespeare antennas. My setup has a 6 foot extension pole. On one occasion my wife was on a dock trying to get the boat tied up in a wind. The antenna was down and lying along the roof. A gust of wind came and she felt the boat was getting away from her. In her haste she grabbed the antenna to pull the boat back (she was going for the roof rail). Anyway she pulled on the antenna and got the boat under control again. Turns out that this action bent the stainless steel antenna mount but did not damage the antenna itself.
Yes, I know this is not the purpose of antennas, but you probably couldn’t do this with your Moran. |
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thataway
Joined: 02 Nov 2003
Posts: 20814
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
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| Posted: Sun Apr 07, 2024 10:21 am Post subject: |
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| Quote: | | Yes, I know this is not the purpose of antennas, but you probably couldn’t do this with your Moran. |
Morad antenna:
These are mounted on a SS pipe either 2' or 4' (can be more on commercial, LE or Military vessel). These are far stronger than any fiberglass antenna. The cylinder is anodized aluminum and very strong.
One of the reasons I use a SS pipe extension base, is if someone grabs the antenna, it will not be damaged. You could bend the whip, but whips are easily replaced. |
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colbysmith
Joined: 02 Oct 2011
Posts: 4551
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
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| Posted: Sun Apr 07, 2024 12:21 pm Post subject: |
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| Quote: | These are mounted on a SS pipe either 2' or 4' (can be more on commercial, LE or Military vessel). These are far stronger than any fiberglass antenna. The cylinder is anodized aluminum and very strong.
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Thinking about this, I wonder what would happen if the Morad hit an air obstruction. I have considered replacing my Shakespeares with Morad next time I need a replacement. But I also want the current height of 8 foot above my boats roof. The SS is not going to flex like a fiberglass. So would it break the mount or possibly crack the fiberglass bulkhead? Mounts are cheaper than either type antenna. Patching a fiberglass bulkhead might not be. |
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thataway
Joined: 02 Nov 2003
Posts: 20814
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
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| Posted: Sun Apr 07, 2024 2:41 pm Post subject: |
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| Quote: | | Thinking about this, I wonder what would happen if the Morad hit an air obstruction. I have considered replacing my Shakespeares with Morad next time I need a replacement. But I also want the current height of 8 foot above my boats roof. The SS is not going to flex like a fiberglass. So would it break the mount or possibly crack the fiberglass bulkhead? Mounts are cheaper than either type antenna. Patching a fiberglass bulkhead might not be. |
Colby
SS whip is extremely flexible--far more than flexible than a fiberglass antenna. You could bend the whip permanently..it is approximartly 1/8" diameter. The whip is about 36" long, The Aluminum tube is about 16" long. Total length is 4.5 feet. If you plan on hitting objects with your marine VHF antenna, I advise get a spring base, as used on many Ham antennas for vehicles. It may take a little searching to find one in SS. Or use a plastic base. It will crack far sooner than a SS base will.
To get to the 8' at the top you will need a 3.5' long SS pipe for the extension. If you hit that, then the obstruction will most likely take out other items on the cabin top such as your radar. (Incidentally most radio guys do not approve of flying flags from your antenna. It puts undo stress on it.)
Morad also makes a 10 dB gain antenna. This is a brute, and it could cause damage as you suggest, but it is rarely used on vessels less than 50 feet. Any long antenna needs a second support. I don't have any handy photos, but the HF SSB fiberglass antenna for marine radios is 23' long. On my Cal 46 it was mounted on the deck and then supported with a stand off by my 9' tall radar arch on the back of the boat. That arch also had my Radar, 2 meter meter antenna, a back up (for the mast head) primary VHF radio antenna, air horns and another type of ham antennas: Firesticks; Hamsticks, which can be had with a SS spring base.
I am not sure what "Bulkhead" would be involved with mounting the VHF radio antenna--If the Cabin top is only 1/4" thick fiber glass, it should be backed up with a larger than the footprint of the antenna mount (Even Starboard, but aluminum plate would be better.). The 25's roofs are not all built the same. Some have no core in part--and where the core is can vary. (The raised portion vs the lower outer side/forward part.). Ideally the core would be in both sections--and even then any antenna should have fender washers under the four 1/4" bolts for the antenna base. |
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