Hey folks, last summer was the first season with the new-to-us boat, and one of the improvements I have to make this spring is the VHF range. The boat is well equipped with B&G electronics, however the B&G V50 VHF has never had more than a mile or two of range in the HI transmit position (yes the surveyor checked the VHF, using an automated echo-back station, not a great test).
I plan to replace both the Antenna at the top of the mast and the run of cable that goes through the mast. The B&G install manual doesn't mention the Antenna or cable type to use and I'm still waiting to hear back from tech support.
I assume the antenna and cable are original to the boat, not sure if they were replaced during the electronics upgrade in 2015. I see RG-58/U, RG-8X and LMR-400 as options, ranging in price and efficiency (signal loss). Can anyone recommend a proper Antenna to replace the Shakespeare whip and the best cable?
Thanks again!
Mike
Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA
I have a Metz anntena and get about 25 miles range at 25 watts power with mast head mounting: https://www.defender.com/product3.jsp?name=metz-206-manta-6-vhf-antenna&path=-1|344|2028695|2029060&id=69993
I used Anchor RX cable: https://www.defender.com/product3.jsp?path=-1|344|2028695|2029068&id=1785923
There is also RX 213 cable, but it is probably is too thick for the mast conduit.
I used Shakespeare Centerpin Gold-Plated PL-259 Connectors and heat shrinked the fittings. This worked fine, but my understanding is solder connectors are better.
Ron St. Onge
C36-MKII Hull 1384
Ron St. Onge
1995 Catalina 36 MKII Hull 1384
Ron, thanks for the great advice. I will be picking up the Metz antenna.
Mike
Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA
Mike,
Before starting this project make sure that all you want is an improvment in the VHF radio 'communications' area and not want to move to an improvment in your AIS as well. (Transmit & Receive)
As I recall the B&G V-50 was a VHF transceiver with a receive only AIS set up and for the sake of discussion, we'll assume that where that's where you want to wind up. The METZ type 206 ($60.00) would be ideal for your mast head application. Feed this with 75 feet LMR-400 co-ax and you should have an ideal set up. See cable prices at https://www.gigaparts.com/75-lmr-400-times-microwave-ultra-flex-coaxial-cable.html cost is about $120.00. Lowest price around. Follow Ron's suggestions above.
Some technical things you should be aware of at: 150 mHz the 3 db point in many coax cables occurs at 100 feet. (you'll be using 75 feet) That means in 100 feet of co-ax cable, you have lost almost half of your transmitter's power in the coaxial cable itself. So, if your transmitter's true power output is 20 watts output you'll really be only seeing 10 watts by the time it gets to the antenna 100 feet away. This makes the case for the better and more expensive lower loss coaxial cable - but 10 watts is plenty in this application. Recall too, that VHF communications is very much line of sight and you are up 50 feet high on the mast. If you can see the receiving antenna they will hear with a lot less power than 10 watts.
Before ordering the cable check mechanical size of the cable for fit in to the mast tube. I think the outside edge of LMR-400 is 3/8" of an inch. Be sure you put a drip loop in the cable and seal the connectors against the rain.
Bill
Bill Dolan 1990 Catalina C-36 MKI - Hull #1041 'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'
Bill, thanks (again) for the great advice. As for the AIS, it seemed to be working fine. I had AIS displayed on my chart plotter last season. I assume the signal was via the existing antenna. Just a few questions: I agree with your assesment (and Nigel Calder's) on LMR-400, I plan to go with that as long as it fits in the mast conduit.
1. The cable you recommended doesn't mention "marine grade". Is this not a concern in this application? (they do mention it can be used in "almost any application".
2. I think I already know the answer to this one, but since I am replacing the cable in the mast, I assume I should replace the cable between the mast foot and the radio itself? Probably best to eliminate any other possibilty of problems with the rest of the cable. The 75' will be adequate for both the mast run and the run from the foot to the radio?
3. Can you point me toward the connectors you used? Can I re-use the connectors off my existing cable? ( I will read the printing on the cable jacket to identify what kind of cable I currently have when I go to the boat this week). I'm assuming I'll just start with fresh connectors since the old ones are probably soldered or crimped.
4. Drip loop at the base of the mast? Can you detail where you put your drip loop?
See attached picture of my existing cable, disconnected at the base of the mast. (Spar is down and on the rack). Thanks again for the advice. Much appreciated.
Mike
Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA
Mike;
This afternoon, I will speak to a chap who does electronics on boats as his principal business and I know he has installed various configurations on Catalina 36's. I want to ask him if going the lower loss LMR - 400 is actually worth the effort and more importantly, will the LMR-400 cable will actually fit inside the mast wiring tube of a Catalina 36. The connector in the picture is a PL-259 used in RG-8 and RG 58 (thinner) cable.
Why don't you hold off a day buying anything until I speak with him and I'll get back with you with some first hand knowledge.
If you wish to send me a PM you can do so; here on the forum.
Bill
Bill Dolan 1990 Catalina C-36 MKI - Hull #1041 'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'
Hey Bill, will do, I've only bought the antenna so far. I was going to take a ride down tomorrow and measure the conduit in the mast. My memory is foggy, but I thought I remember having 3 runs of PVC pipe running inside the mast, on the forward side of the internal roller furler. The roller furler makes it a bit crowded inside the mast, hopefully it's not a factor . I'll try you on the PM.
Mike
Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA