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formerly 'BoatyardBoy'
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Discussion Starter · #1 ·
I will be installing all the final goodies on my mast when I finally get back from offshore, I have had some questions regarding it.

First, my mast is 65' and the line from mast at keel to radio location is probably 15' or so. So well say 80' total run of wire. I initially ran RG-8x up the mast but soon found out too much loss(It will just be a spare for another antenna). So I'm ordering Beldon 9913F7 wire with Amphenol 083-ISP connectors from theAntennaFarm. I should be correct in this, yes?

The main question, I am using a GAM SS-2 whip antenna, and will be located at the top of the masthead, on the side of the mast. My concern is that I will also have a 3' aluminium pole with my red and green all around lights (red up top, green mounted near the bottom). I have read that you shouldn't mount the antenna near metal objects like this..

Am I OK with this or do i need to make a carbon fiber pole to mount the lights instead? Or will this be negligible and shouldn't worry about it. It's coming down to crunch time and I need to get the mast stepped.

Note: I chose to use red/green lights instead of a tricolor, as I think tri's are not a visible as the former option. As a profession mariner, this is my professional opinion and I already bought the lights.
 

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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.
 

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formerly 'BoatyardBoy'
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534 Posts
Discussion Starter · #3 ·
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.
I see, well I looked at the 180° lights, I suppose I could return the 360 ones for exchange. 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. What you think? I would spend slightly more on the lights but I would save time of fabricating the pole mount, especially if I had to do carbon. Plus not having transmission issues I would say it's even..

A picture with friends my mast head.
 

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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.
 

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I see, well I looked at the 180° lights, I suppose I could return the 360 ones for exchange. 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. What you think? I would spend slightly more on the lights but I would save time of fabricating the pole mount, especially if I had to do carbon. Plus not having transmission issues I would say it's even..

A picture with friends my mast head.
An Isomat spar?
 

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formerly 'BoatyardBoy'
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534 Posts
Discussion Starter · #6 ·
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.
That's what I figured, just verifying said thought. Thanks, I'll post some pictures when it's done. Much appreciated.

An Isomat spar?
Sure is, the NG-105, the big one. Do you have one as well?
 

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formerly 'BoatyardBoy'
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534 Posts
Discussion Starter · #7 ·
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.
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.
 

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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.
 

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Just a note re metal verses carbon fiber mast - carbon fiber is no better - it also is a conductor and will interfere with the radio. Now how much I am not sure but I wouldn't be concerned on my own boat If the SWR (standing wavw ratio) was within limits for the radio.
 

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

I'd appreciate your advice on how to mount these things to avoid interference. I have all winter to fabricate extension arms, brackets, etc., to make sure both wind gadgets are not interfering. Just let me know what you suggest.
 

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formerly 'BoatyardBoy'
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Discussion Starter · #11 ·
If the mast is still down you might want to make some Starboard spacers between the lights and the mast. Just an idea.
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?
 

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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.
 

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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.
 

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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.
Your friend is mistaken. Nothing beats putting the antenna higher.
 

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formerly 'BoatyardBoy'
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534 Posts
Discussion Starter · #15 ·
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.
Alright, well I guess I'll get some starboard and make it happen. I "knew" I should and I'm glad you pointed it out because I was ignorant of it. I'll see if Lowes has it at home, if not I'll order some.
 

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formerly 'BoatyardBoy'
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Discussion Starter · #16 ·
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!
 

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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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formerly 'BoatyardBoy'
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Discussion Starter · #18 ·
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.

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.
I do not.. But I'll try Harbor Freight and Lowes to see what they have. I appreciate the advice you have given me
 

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BYB.. good thing you ordered your material.. Starboard is not something that our local HD/Lowes etc is likely to carry.

I've gotten good deals, however, on off-cuts from a plastics retailer. Scraps are all you really need for that kind of project though it's useful to have some kicking around esp when you're still in the 'project' stage.
 

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formerly 'BoatyardBoy'
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Discussion Starter · #20 ·
BYB.. good thing you ordered your material.. Starboard is not something that our local HD/Lowes etc is likely to carry.

I've gotten good deals, however, on off-cuts from a plastics retailer. Scraps are all you really need for that kind of project though it's useful to have some kicking around esp when you're still in the 'project' stage.
Yea that's what I figured so I just ordered a 12x27 sheet of 1/2". It was a couple bucks cheaper from the eBay shop than Defender and had free shipping. I figured what I don't use I can use for other projects down the road. The stuff doesn't go bad.

- Ronnie...on the geaux
 
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