Hey all, we've had a good amount of snow and cold weather up here in the north hinterland...all we can do is watch the sailing vids on Youtube to get us through. Hope you guys in the warmer areas are enjoying your sailing
Actually, spring is around the corner and I'm looking forward to some projects on my C-22. One of the things I wanted to consider is a combination anchor light, antenna and wind direction indicator at the top of the mast. I've seen another forum member post pictures of such a setup here and that looks to be pretty much what I'm after. I didn't find this setup at West Marine though. Does anyone know where I can buy one? Also, I take it that the antenna is for VHF but can it also be used simultaneously for a regular AM/FM radio? How are some of you doing VHF and AM/FM radio together? Do I really need two antennas, one for each?
You may want to reconsider the antenna on top of the mast. I originally had one and found I could not communicate with boats within a mile or so and knowing the area you sail this can happen quite often.
Trev is absolutely correct. You need to think about how you will use the VHF and where you sail. The antennas transmit on a plane. Or better descritption, picture a round dinner plate. The center of your plate is the antenna. The plate is the signal pattern. If the plate is to high you literally transmit right over the top of boats that are close. Happens to me on Destiny a lot since the antenna is 55' in the air! I actually installed a second radio system with an antenna on the radar arch just so I could communicate ship to shore and to boats close at hand!
This is not to discourage putting your antenna on top, just a pointer to some things will will find out after install anyway! Your antenna on top will most certainly give you the longest range so if you sail off shore and every bit of range is important, on top is certainly the best way to go.
If memory serves Alan custom made a plate for Honu. He will likely be able to help in the design. Also I believe someone else here did the same but I can not remember who! LOL!
Thank you Scott, vary well put I did not realize that. And I will add that a cell phone is a great help on a boat, and be sure to add a phone book. Just in case you need to look up a phone number, to be able to call for help.
Bryan, for all the times I helped you raise and lower your mast, I can remember if you have the cast mast head or one like mine
Here is a shot of the set-up on Happy Place.
Masthead light on top
VHS antenna mounted on side
Windex mounted on rod extended off the back (other side of entenna)
The FM radio entenna is actually inside the boat.
...and to help you get through the rest of the winter... remember this day last August
Love the nice white sails
H:)ppy Place
78 Chrysler 22
You can go to a Zen Master or you can go Sailing, either way you end up in about the same place..... a Happy Place
I stole Mcrandall's idea and built the exact same as he did, with the led lights and all. It was an extremely easy set up to do and the led lighs really help.
$30 will get you a spliter for your am/fm and vhf to plug into thid will let you use 1 antenna. It works great.
We listen and communicate with bridge and lock traffic from long distances. We need the range the masthead gives. Short range transmission is easily solved with a hand held.
Bob T . . .
1979 Chrysler 26 "Indecision"
Dallas, Texas / I-45 / Galveston Bay
Hey all! On the subject and to further on what was said earlier... if you do mainly short range stuff in a small lake as I do, do you think it possible to mount the VHF antenna halfway up the mast without interfering with sailing systems?
CaptainScott wrote:If memory serves Alan custom made a plate for Honu. He will likely be able to help in the design. Also I believe someone else here did the same but I can not remember who! LOL!
Scott
Here is what I did.
Now I have altered it since this photo was taken.
The Wind vein has been moved to the Little platform the Running light is on and the antenna has moved back to the end of the arm.
I've not used this setup anyplace but my driveway yet so I can't talk to it's performance. I intend to use the antenna for radio reception, as In AM-FM. I use a hand held water proof radio which I keep in mt life vest. I sail coastal, rives and lakes so the top of the mast would not work well for me unless I was really headed out to sea.
Thanks
Alan
Last edited by Alanhod on Mon Feb 11, 2013 6:31 pm, edited 1 time in total.
Bondo...its not the power , its the radiation pattern. Evidently these vertically polarized antennas have a nearly line of sight radiation pattern( no personal experience on this topic) judging by the comments from those who have tried mast top mounting. Thus there seems to be no radiation below the horizontal plane below the antenna base. Therefore the signal skips over the top of nearby boats and shore stations.
Only a guess here. I would not mount anywhere lower on the mast.
Actually, the radiation pattern is more like a donut, with the antenna whip standing in the "hole". Now, depending on the gain of your antenna, your pattern varies.
The theoretical radiation pattern of a zero gain antenna is a perfect sphere. A perfect example of this type of antenna does not exist, but it gives a basis to compare. Basically, the higher the gain, the squattier that sphere becomes. Perhaps those that are having problems close in are using a higher gain antenna and are "skipping over" those nearer in (astrorad). Anyone who has issues know the gain of your antenna?
Know that many factors affect radiation patterns of antennas. Moving it down on the mast will provide a large "shadow" where transmissions and receptions will be blocked.
Now, I don't doubt that folks are having problems as stated, but I have not experienced it. I have many, many customers that used their radios near their intended target (that is, on our smaller lake and out on Lake Michigan.) I have used a hand-held on the docks and directed sailboats to open slips rather than just yelling to them. I just haven't run in to it or heard any complaints. I do see the potential, especially with higher gain antennas, but our masts are just not that tall either. I'll be looking into the issue and poll my customers. Hope to experience it so I might learn the cause.
Hey thanks for all the great comments and info everyone. I wasn't aware of the issues regarding the radiation field of the VHF antenna if mounted at the top of the mast. That being the case, someone mentioned using a handheld VHF for short range areas and the masthead for longer ranges and I will keep that in mind. Mcrandall your setup is exactly what I wanted to build, it looks real good. So, based on the metal shavings I saw on the ground in your picture, it looks like a custom job of yours and not something you can buy? I'm not adverse to projects like that...so maybe I'll be copying your design and making it myself, if you don't mind. Thanks for the pic!
Bondo, yes that picture of my boat is definitely inspiring! Now I'll go and renew a couple of subscriptions to sailing magazines...
By all means, delighted to have it copied/improved upon! That's what this site is all about, right?!
Please check out my pics at the link in my signature block. You'll see I used aluminum angle stock for the c-channel base and aluminum bar stock for the "legs". Aluminum rivets help to eliminate galvanic issues.
