Please Recommend a Quality VHF Masthead Antenna

[funk-an-bord.de]

Originally Posted by goboatingnow

Gsm is limited by the timing advance issue in the base station.

I definitly can agree:
On the canarias island of Tenerife a cellular antenna is mounted at apr. 2.500 meter.
The radio horizont reaches 125 nm up to the Islas Salvages half the way to Madeira.
I measured a coverage of the cellular station,
but the phone could not log in.
Willy

[sdrformariners]

Originally Posted by Dockhead

My existing masthead VHF antenna is a skinny steel whip combined with winded, fed by a skinny coax cable. My mast is down and I'm taking the chance to replace everything.

I have no complaints about VHF comms. I use an Icom M604 and get good signal reports from great distances (75 feet of height probably don't hurt), but why not take the chance to install something good? Anyone have any recommendations?

Buy a half-wave /0.9m / fiberglass antenna, monopole in radio terms, and install it using LMR-400 or LMR-600 radio coax.
Cable will be expensive, but you will not lose so much signal due to cable loss.

If reliable and sturdy mounting can be achieved, I'd have two masthead antennas with good quality used - One for vhf, one for AIS.

AIS is at 162 MHz, almost the same frequency as the marine band at 156-162, so a marine VHF antenna will be just as good.

If you need the best possible performance for the lowest price, I'd build two masthead antennas out of house grounding wire, two-piece fishing rods and using an antenna analyser.
Connect antennas to transceiver and antenna analyser inline, then tune the antenna for a 1:1 SWR for 156.8 MHz. This way, you can built the antenna yourself, get the best performance and save £££s along the way.

Just my 2p.

Akos

[El Rubio]

Originally Posted by sdrformariners

Buy a half-wave /0.9m / fiberglass antenna, monopole in radio terms, and install it using LMR-400 or LMR-600 radio coax.
Cable will be expensive, but you will not lose so much signal due to cable loss.

If reliable and sturdy mounting can be achieved, I'd have two masthead antennas with good quality used - One for vhf, one for AIS.

AIS is at 162 MHz, almost the same frequency as the marine band at 156-162, so a marine VHF antenna will be just as good.

If you need the best possible performance for the lowest price, I'd build two masthead antennas out of house grounding wire, two-piece fishing rods and using an antenna analyser.
Connect antennas to transceiver and antenna analyser inline, then tune the antenna for a 1:1 SWR for 156.8 MHz. This way, you can built the antenna yourself, get the best performance and save £££s along the way.

Just my 2p.

Akos

LMR600? I understand the disagreements with me by some here when i recommend LMR240, but 600 is way overkill for VHF runs around 100' or less, and two runs of it would be over the top extreme. Any signal improvement will be undetectable and expensive.

[sdrformariners]

Originally Posted by El Rubio

LMR600? I understand the disagreements with me by some here when i recommend LMR240, but 600 is way overkill for VHF runs around 100' or less, and two runs of it would be over the top extreme. Any signal improvement will be undetectable and expensive.

You are absolutely right to recommend LMR-240, and yes, I also think LMR-600 is overkill. So what? Eventually your life may depend on your antenna system.
LMR-400 has half the attenuation of 240, so that extra few dB might come handy.

[mub]

For me...

I have 2 vhf antennas mounted. Both metz mantra 6 so I could interchange parts as needed. I also carry spares for them.

Both are run with LM400-flex because there is some movement in both lines.. and the lines both are pulled in tight spaces.
A single over bend pulling the 400 and you have undone all that work.


Mub

Sent from my HTC One X using Cruisers Sailing Forum mobile app

[Dockhead]

Originally Posted by sdrformariners

Buy a half-wave /0.9m / fiberglass antenna, monopole in radio terms, and install it using LMR-400 or LMR-600 radio coax.
Cable will be expensive, but you will not lose so much signal due to cable loss.

If reliable and sturdy mounting can be achieved, I'd have two masthead antennas with good quality used - One for vhf, one for AIS.

AIS is at 162 MHz, almost the same frequency as the marine band at 156-162, so a marine VHF antenna will be just as good.

If you need the best possible performance for the lowest price, I'd build two masthead antennas out of house grounding wire, two-piece fishing rods and using an antenna analyser.
Connect antennas to transceiver and antenna analyser inline, then tune the antenna for a 1:1 SWR for 156.8 MHz. This way, you can built the antenna yourself, get the best performance and save £££s along the way.

Just my 2p.

Akos

If you read through the thread, you'll see that I long ago (about a year ago) chose a Shakespeare Galaxy antenna (internal dipole), and installed it, using RG213U cable! My AIS transceiver uses a ham radio antenna (Diamond VHF/UHF) mounted on the first spreader. It all works very well. I had a "weak but readable" signal report from Solent Coast Guard at 60 miles, from Cherbourg. Using 1 watt!!! Typical AIS range is 40 miles.

[sdrformariners]

Originally Posted by Dockhead

If you read through the thread, you'll see that I long ago (about a year ago) chose a Shakespeare Galaxy antenna (internal dipole), and installed it, using RG213U cable! My AIS transceiver uses a ham radio antenna (Diamond VHF/UHF) mounted on the first spreader. It all works very well. I had a "weak but readable" signal report from Solent Coast Guard at 60 miles, from Cherbourg. Using 1 watt!!! Typical AIS range is 40 miles.

RG 213U has double the loss of LMR-400, see here: Coax Attenuation Chart

You are losing 1dB, which is 20% of transmitted power with a 75 feet mast cable run with your RG213-U versus LMR-400.
20% is not that much, certainly not worth recabling for.

Solent Coast Guard has much better antenna arrays than a merchant vessel or a yacht or a handheld, 60 miles range is nothing to write home about. They are at liberty to use highly directional Yagi arrays, after all, they are the coastguard.

A Diamond is a good brand and make antennas with good reviews, still, it is possible that it is optimised for ham 144MHz.

AIS range depends on the transmitting vessel and the receiver vessel's antenna location and antenna type, writing AIS has a 40 mile range is simply not true.
Normally AIS has a range of at least 15 miles, thought due to ducting etc it is possible to intermittently pick up AIS over 100 miles away e.g. off the coast of Africa.
A 10 mile AIS range is more than enough, as even on a 6 nm range radar you'll show up as the radar is offset.

[Dockhead]

Originally Posted by sdrformariners

RG 213U has double the loss of LMR-400, see here: Coax Attenuation Chart

You are losing 1dB, which is 20% of transmitted power with a 75 feet mast cable run with your RG213-U versus LMR-400.
20% is not that much, certainly not worth recabling for.

Solent Coast Guard has much better antenna arrays than a merchant vessel or a yacht or a handheld, 60 miles range is nothing to write home about. They are at liberty to use highly directional Yagi arrays, after all, they are the coastguard.

A Diamond is a good brand and make antennas with good reviews, still, it is possible that it is optimised for ham 144MHz.

AIS range depends on the transmitting vessel and the receiver vessel's antenna location and antenna type, writing AIS has a 40 mile range is simply not true.
Normally AIS has a range of at least 15 miles, thought due to ducting etc it is possible to intermittently pick up AIS over 100 miles away e.g. off the coast of Africa.
A 10 mile AIS range is more than enough, as even on a 6 nm range radar you'll show up as the radar is offset.

Yes, but 60 miles on ONE WATT! With respect, I think that IS something to write home about.

I chose RG213 because I didn't want to risk problems with foam core cable like LMR400. My mast is 75 feet tall and it is not a trivial expense to unstep it, and you can't replace the cable with the mast up. RG213 is solid core and so less susceptible to moisture penetration or deformation.

I can live without the one dB. As it is, I have had to keep my transceiver on LOC to avoid being driven crazy by listening all day to the French across the Channel, and 1 watt (low power) is now my normal setting.

[El Rubio]

One dB loss is insignificant in real world applications.

[transmitterdan]

You are correct but be prepared with flame retardant.

[JoeFish]

Originally Posted by s/v Jedi

The Shakespeare Little Giant is 1/2 wave, not 5/8. It is a center fed dipole unlike the average grounded designs, which keeps the receiver S/N nice and clean.

Every user notices the big improvement this antenna makes and that is fact, not speculation

This is all well & good, but this is a big unit at the mast head. Those of us who race and cruise have weight & windage concerns which blur the region of compromise on these decisions.

What I have yet to see is a decent comparison between reception, transmission, windage and weight factored & presented so people can make a rational decision given their personal requirements.

[transmitterdan]

Joe,

The light Metz wire antenna is fine. The height of the antenna is more important than the gain. There is no good argument for a tall heavy fiberglass antenna at the mast head.

There are other brands similar to the Metz base loaded wire whip antenna. My experience is with the Metz and the quality is pretty good.

[s/v Jedi]

Originally Posted by transmitterdan

Joe,

The light Metz wire antenna is fine. The height of the antenna is more important than the gain. There is no good argument for a tall heavy fiberglass antenna at the mast head.

There are other brands similar to the Metz base loaded wire whip antenna. My experience is with the Metz and the quality is pretty good.

The shakespear little giant is.... Here it comes... Little. The big ones are 8-12dB for motoryachts.

It is a dipole so less noise than base loaded designs which are ground plane antennas.

[JoeFish]

Originally Posted by s/v Jedi

The shakespear little giant is.... Here it comes... Little. The big ones are 8-12dB for motoryachts.

That is not a little unit. Maybe if you're on some massive boat with a phone pole for a mast, but a 48-54" 1.5cm thick whip at the masthead is an absurd amount of windage compared to some options.

Again, until there's a chart showing surface area, transmit, receive performance, etc. then you're still trying to make 'one size fits all' recommendations.

Under ideal conditions we listen to Australian broadcasts on the SSB from Alaska, some times, not. Anecdotal comments are nice, but subject to much variability.

[Dockhead]

Originally Posted by s/v Jedi

The Shakespeare Little Giant is 1/2 wave, not 5/8. It is a center fed dipole unlike the average grounded designs, which keeps the receiver S/N nice and clean.

Every user notices the big improvement this antenna makes and that is fact, not speculation

My continuing experiences with mine, in service now for more than a year, confirm this. Recent loud and clear from Helsinki Radio, from Estonia, 100 miles away. Dramatic improvement over my previous whip antenna.