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What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Thu Sep 21, 2017 6:28 am
by hotstonp
Greetings one and all,

I am about to loose my 3rd VHF aerial in 3 years. If I get caught in roughs, have a rough passage to windward or spend too long reefing in a good blow with a bit of a sea then I seem to loosen my VHF aerial and if I am not quit enough I saw goodbye to my aerial and windex. So what do you use? How to you fix it?

Many thanks in advance
Keep well
Peter

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Thu Sep 21, 2017 11:50 am
by BillSmith
What's happening to your VHF antennae? Loosening at the attachment point or whipped to pieces? Loose screw? Loctite on threads!

We did a remove and repair on our B&G wind anemometer. Used a rigger for that. No problems with vane, VHF or B&G after a season in SF Bay's very brisk breezes.

Are there any lines blowing over the top and doing damage? One device banging into the other in high winds?

You lose range on VHF, but have seen many a boat with antennae affixed to a aft radar arch or bimini support. Better lower and working than aloft in not functioning.

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Thu Sep 21, 2017 1:00 pm
by mike cunningham
I just lost a long post I made on this topic. I sent a copy of it to Practical Sailor before I lost the darn thing.

Bottom line is I have Tram antenna and it twists itself off the base in a seaway. I lost two of them before I figured this out. I tested this in the garage with a new antenna and as able to walk the aerial off the base by simulating the circular motion of pitch and roll while grasping the antenna assembly in my hand. The problem is the way my antenna is fabricated and designed, it is not obvious the aerial base actually screws into the antenna base. There are set screws for the aerial wire but no screws for the associated base so the aerial is just screwed on and you are unlikely to check it when you mount the antenna because you don't know there are threads. You may have the same issue.

Use locktight and tighten as much as possible was my solution. I did not want to replace the whole thing because I had some complex RF wiring at the masthead and did not want to redo it. I've sailed a couple hunderd miles in a seaway with the fix and it seems to be holding.

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Mon Sep 25, 2017 11:00 am
by hotstonp
Thanks Mike & Bill,

Mike I think you are right, mine is unwinding itself due to the motion of the mast. It just happens faster in aggressive short chop.

I had thought of using loctite but wasn't sure about it... I think I will now. Just wait for half term and then hoist my 10 year old daughter up there to fix it then?

Keep well
Peter

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Mon Sep 25, 2017 12:09 pm
by mike cunningham
Agree with your solution. I have a topclimber which I use to get up there. It is a pain. When I was in Hawaii, one of the delivery crew was a young scrawny guy who was up the mast in about three minutes, He said the topclimber was a waste of time and had me hoist him up. Replaced the antenna...done. Unfortunately this was antenna number two and we lost it again before I figured out what was going on. Having said that I am all in favor of having someone young and nimble do the climbing. For replacement number three, I had the mast out of the boat. Oh for being young and scrawny.

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Fri Jul 13, 2018 10:10 am
by hotstonp
well a good while later..

Daughter went up and unscrewed the old one. The whip had actually snapped off so I have put yet another one on as I really miss the windex. At the same time I have taken Bill's advice and put a spare VHF whip aerial on the comms mast on the stern, it is all wired up with a loose lead next to the radio should I need to swap it over. If I am feeling flush then I will purchase a proper switch.

Keep well
Peter

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Sat Jul 14, 2018 6:22 am
by GeoffSchultz
I'm way late on this conversation, but I have 2 Metz VHF antennas on my mast head unit. 1 is for the VHF and the other is for the AIS. The AIS one has an antenna splitter on it so I can utilize it as a spare if the main one or cable fails. Note that I pulled RG8X cable, which is extremely low loss, and I'm amazed at what I can pick up that other boats can't.

I also installed a video camera with a polarizer on it which feeds the the display on my B&G chartplotter. We spend a lot of time in reef/coral strewn areas and this really aids when maneuvering in these areas, especially when the charts are completely unreliable.

Note that the the wind device mounts just above the camera and the windex mounts on a bar which protrudes aft. This is a very busy masthead unit.

-- Geoff

2017-10-24 11.34.47.jpg
Masthead unit
2017-10-24 11.34.47.jpg (64.98 KiB) Viewed 1122 times

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Sat Jul 14, 2018 12:02 pm
by hotstonp
Hi Geoff

That is such a good mast head unit. Certainly gives me pause for thought.

Keep well
Peter

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Sun Aug 12, 2018 10:19 am
by mike cunningham
I can"t believe it. I have lost yet another VHF antenna!! This is number three. It came ioff sometime during the return trip from Kauai to SF. Fortunately race rules require us to carry an emergency antenna so I was able to rig that on the flag halyard and get decent AIS reception but with much reduced range. Same with Radio. I am going to have to scrap the whole Tram antenna and go with another manufacturer.

Re: What do you use as your VHF aerial? Freedom 33 Cat Sloop

PostPosted: Sun Aug 12, 2018 3:36 pm
by gamayun
Welcome back, Mike!! Crazy trip. So great to have done it with you. I'm pretty sure mine's a Shakespeare antenna with a backup on the solar arch attached to a splitter in the nav station. I'd contact the manufacturer of your antenna and let them know what happened. Maybe they'll send you a replacement or make suggestion on preventing the issue from happening again...just an idea.