Coax Cable Feed-Thru

Aug 17, 2017
44
Catalina Catalina 30 MKII 5346 Melbourne Yacht Club
I am replacing the VHF antenna and cable on my '272LE. I intend to run the coax continuously from the antenna, down through the mast, through the cabin roof, and through the cabin to the radio. There is an existing coax panel connector which needs to be removed so that the cable is continuous. Do any of you know if there is a feed-through fitting that I can use to make the transition water-tight?
 
Sep 25, 2008
7,077
Alden 50 Sarasota, Florida
I don’t know but I’d be interested hearing why you prefer to use a continuous run of coax.
 

AaronD

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Aug 10, 2014
723
Catalina 22 9874 Newberg, OR / Olympia, WA
Several companies make deck pass-throughs often called cable clams: E.g. Blue Sea or ScanStrut

I've used several plastic ScanStruts with good results. They're also available in stainless - presumably worth considering if you live in a higher-UV location.
 
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Aug 17, 2017
44
Catalina Catalina 30 MKII 5346 Melbourne Yacht Club
Several companies make deck pass-throughs often called cable clams: E.g. Blue Sea or ScanStrut

I've used several plastic ScanStruts with good results. They're also available in stainless - presumably worth considering if you live in a higher-UV location.
Thanks, AaronD!
 
Sep 25, 2008
7,077
Alden 50 Sarasota, Florida
Adding connectors increases insertion loss and VSWR, well-known RF signal impediments.
I know this isn’t what you are seeking here but I can’t help comment-
Good quality properly soldered connectors create no insertion loss. I’ve daisy-chained multiple connectors and measured it as have others. There is no evidence I am aware of that anyone ever found any contrary result. If you have any, I’d like to read it.

If that’s your sole reason, I’d urge you to review data from reputable sources before using a continuous run which serves only as an impediment to mast stepping and routine maintenance.

Parenthetically, even if there was any insertion loss, that doesn’t result in any increase in SWR.
 
Aug 17, 2017
44
Catalina Catalina 30 MKII 5346 Melbourne Yacht Club
I know this isn’t what you are seeking here but I can’t help comment-
I'm not going to spend a lot of time researching or debating this. But in my experience, every connector I've bought in my line of work specifies, among other things, an insertion loss (typically tenths of a db) and a VSWR (typically 1.0 - 1.5 db), but always nonzero and positive. You can look in any connector catalog you please; they will be specified.
There is always the assumption that any solder joint will be "perfect," and they never are. And in this case, we're talking about a technician who is not factory certified.
I'm quite satisfied with my minimal connector approach.
 
Apr 22, 2011
865
Hunter 27 Pecan Grove, Oriental, NC
Continual runs of cables and electrical wires from the mast can be a real problem when it comes time to unstep the mast. I had to cut all of them when I had the mast unstepped last year. If you do decide on a continual run of vhf cable, I suggest you create a loop of cable inside and near the base of the mast to allow enough slack to install a connector if the mast is unstepped.
 
Sep 25, 2008
7,077
Alden 50 Sarasota, Florida
I'm not going to spend a lot of time researching or debating this. But in my experience, every connector I've bought in my line of work specifies, among other things, an insertion loss (typically tenths of a db) and a VSWR (typically 1.0 - 1.5 db), but always nonzero and positive. You can look in any connector catalog you please; they will be specified.
There is always the assumption that any solder joint will be "perfect," and they never are. And in this case, we're talking about a technician who is not factory certified.
I'm quite satisfied with my minimal connector approach.
SWR isn’t measured as dB loss. Neither are PL258, PL 259 or double female coax connectors.
Your choice but a little reading will save a lot of aggravation later when you need to lower the mast.
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
I see already we have gone off topic. Anyway, besides the sources already mentioned, Sea Dog might also have cable glans. But don't forget to look in the SBO store for cable glans.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
I ran my VHF coax and Radar cables down thru the mast. Clipped the old wires shown in the image. Drilled a hole through the mast step. Prepared a raised tube to stop water from flowing down into the cabin. Opened up the weep holes at the mast base.
D17E5D26-8846-4EC2-BD16-ED6B79434687.jpeg

Used a piece of hose attached to the pipes to form drip loop.
F47C1425-E703-4362-8E45-E24AF59398BE.jpeg

The electrical are ready to be released at the mast base from inside the cabin.
913EB4B6-1DE9-4392-96E8-EFC0E7A1A1B5.jpeg

The Radar and VHF cables are released at their displays and then pulled up through the mast base as the mast is removed. This means no connections and reduced signal loss.

I do not expect to remove the mast again, but capable if needed.
 
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