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· Mermaid Hunter
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The metal pole for your lights WILL interact with your VHF antenna. Not recommended.

Off the top of my head you have two options. Best would be returning your lights and getting two red 180 degree lights and two green 180 degree lights. You can mount the reds on either side of the mast at the top and the greens on either side of the mast 1 meter down. Alternatively you can use the carbon pole you asked about. Note that the power wires running up the pole to the red light WILL interact with your VHF antenna.

Interaction is likely to be directionality as much as anything. That means you may think you have good performance because you can hear traffic from reasonable distance in some directions without realizing that you are missing pretty closely located traffic in other directions.
 

· Mermaid Hunter
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Only thing now, would you recommend putting the lights on port/stbd or fore/aft on the mast? I was thinking port/stbd as the sails would cover up the fore/aft lights much more.
Port/stbd. The biggest issue is avoiding interference with halyards and stays. Besides, that is what the superyachts do. *grin*

I have a combo tricolor (incandescent) and anchor (LED) light on Auspicious that has worked nicely for me offshore. I've often thought of fitting red over green lights and would definitely do port/stbd 180 degree lights. The idea is pretty far down my project list.

For the record (not relevant to you BoatyardBoy since you won't have a tricolor) red over green sailing lights may only be shown with deck-level navigation lights and NOT in combination with a tricolor.
 

· Mermaid Hunter
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Just to show you how I mounted everything... The VHF and the maretron wind sensor aren't mounted yet as I was going to hook that up before I stepped it. Also, the windex isn't mounted either.
If the mast is still down you might want to make some Starboard spacers between the lights and the mast. Just an idea.
 

· Mermaid Hunter
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I'm glad you brought this up awhile ago - it's timely for me. I have a masthead whip antenna mounted against the port side of my mast, with a windex behind it. I've ordered a wireless wind transducer that I was hoping to install on an arm in front of the masthead assembly, and I'll also be replacing the manual windex since the PO mangled it a bit. I also have a small masthead anchor light as well, but it's short enough that it probably does not shadow the antenna.
Is it safe to assume that "masthead whip antenna mounted against the port side of my mast" means a conventional 'L' bracket near the top of the mast so the whip extends above the masthead. Anchor lights should be an issue. The windex (most of which are principally plastic these days) shouldn't be a problem. The transducer should be mounted on a strut to get the rotating magnetic and electric fields away from the antenna, especially if there is a coil at the antenna base. 18" to 20" should be fine.

Quantifying the effects without a lot of modeling, testing, or analysis ($$$) is difficult. I can qualify the potential effects based on experience and the literature if you have any questions.

Yes it's still down, going up in Dec when I get home. Do you think I really should? Haha I don't "feel" like doing it because it's already done and I'd have to make four of those spacers. Is my current set up that bad, granted I know the spacers are better, and probably prudent?
You have to decide if you should. I try to do work on my own boat that meets the standard I would expect of someone I pay, or that others pay me for.

Spacers will reduce vibration on the fasteners and fittings so the installation will last longer.

Making spacers is easy. As you point out you need four. You can make them all at once by clamping the blanks together. Use a contour (or profile) gauge (cheap if you don't have one) to get the shape of the mast at the lights, transfer that to graph paper and glue it to the block of blanks. Cut with a band saw or (carefully) with a jig saw. Drill holes for the mounting hardware and you're done. Extra credit for running around the edges, except for the side against the mast, with a round-over bit. Maybe 30 minutes if you have a shop, and 90 minutes if you have to unpack, work, clean, and repack tools.

You make your choices and take your chances.
 

· Mermaid Hunter
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I have a friend who is responsible for the electronics on many of the Coast Guard ships. He tells me that the signal loss getting to the top of the mast is so great we would be better off mounting the antenna at deck level.

It seems counter intuitive but I would like to see some one runs some tests, which would not be that hard to do.
The math is pretty easy and the engineering well established. Testing isn't necessary. Good connectors and good coax make the masthead quite attractive. If you intend to use cheap coax and crimp-on connectors, well, the pushpit will be okay.

Ended up ordering a sheet of 1/2" off of eBay, didn't want to get home and be disappointed when the box stores didn't hold it. I don't have much time when I get home to splash the boat and step the mast, so it will be waiting for me when I get home. Plus it was free shipping!
Hope that works well. Do you have a profile gauge? You can get the shape of the mast with paper and a pencil but the gauge makes you life really easy and they are cheap. You should be able to get them at Lowes, Home Depot, True Value, Ace, etc.
 
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