Please Recommend a Quality VHF Masthead Antenna

[Jammer]

Originally Posted by scherzoja

The price difference between Classic and Galaxy is 3x and almost double for Galaxy vs Phase III. Does a Classic have the same "range and quality" of a Phase III and if not, why pay 6x? Do the higher-priced models have longer live, less susceptible to corrosion?

These three antennas are electrically similar. Shakespeare is vague about internal construction, but so far as I can determine they are all either end-fed half-wave dipoles or half-wave sleeve dipoles.

For example, does it matter that Phase III is foam filled; whereas, Galaxy is not filled, but has foam doughnuts that keep the core centered? How advantageous is it to have "Silver-plated elements" in the Phase III, but only "Thick brass and copper elements" in the Galaxy. The Classic only has "Brass and copper elements provide standard range and reception". There is no mention of thickness differences between Classic and Galaxy, so if Galaxy element is .001" thicker, there is no lie, but the difference is meaningless.

The cheaper antennas in your list are cost-reduced versions of the Phase III. The main practical difference is in the mount type and means of connection to the coax.



Fiberglass antennas usually fail where the coaxial cable attaches to the antenna. Failures of the internal elements are unusual. They can also be damaged by high winds, usually due to failure of the mounts.


The Shakespeare marine antennas have wimpy mounts compared to LMR products. See for example the Laird FG1560, which the manufacturer rates as being able to withstand 125 MPH winds. I had an FG1563 on a previous boat. These are better, cheaper antennas, as long as you can live without the 1" threaded mount. If you want a big fiberglass antennas, look here.



I would recommend looking at stainless steel whip antennas. They offer less weight aloft, and less windage, will not be damaged by bridges. I believe practical performance is similar on an aluminum mast to the sleeve antennas. Look at the Shakespeare 5242-A, GAM SS-2, and similar.

[Jammer]

Originally Posted by MicHughV

vhf signal range is basically "Line of sight" so higher is aways better.....but there is more to it than that, radio gain is another factor, ie, with a higher gain (dB) when the boat is heeled over, a portion of your signal goes off into the sky and the other portion, but your signal is stronger. A lower gain provides a better spread a the cost of less range.

The idea that VHF signal range is line of sight is a useful rule of thumb but isn't the whole story. VHF propagation is complex and does continue past the horizon, reliably, if there is enough power and gain, due to tropospheric scatter and other effects. Nonetheless, it is certainly true that more height is better.



Most sailboats don't use higher gain antennas. I have experimented with them. Antennas in the 96" long range with actual gains around 5 dBi (many are advertised as 6 dB gain but they're not) do provide improved performance. At reasonable angles of heel (up to around 25°) they will perform at least as well as lower gain antennas, even to points abeam the boat.


The key question to answer regarding VHF installations is one of what you're really trying to accomplish. Who are you going to talk to and at what distance? A careful yet modest installation with a masthead stainless steel whip and RG213 ought to get you 40 miles to similarly equipped vessels and 100 miles to USCG Rescue 21 towers and similar facilities (300' tower, preamp, 100 watts, etc). If you need comms farther offshore than that, you need Iridium or HF.

[MicHughV]

Yes, I've been surprised to hear the US Coast Guard vhf signal in parts of the B'mas....the Abaco's.

Many islands of the B'mas use the vhf as a telephone, pretty much anything goes.

[bstreep]

Just jumping in here. We bought a Morad for our AIS 5 years ago. Couldn’t be happier. They are built so insanely well. They have also engineered the connectors so they are a small diameter.
Next week we are replacing our Shakespeare at the top of the mast with a new Morad. The Shakespeare has failed at 5 years…. Morad is just a “no brainer “ for me.

[s/v Jedi]

Originally Posted by bstreep

Just jumping in here. We bought a Morad for our AIS 5 years ago. Couldn’t be happier. They are built so insanely well. They have also engineered the connectors so they are a small diameter.
Next week we are replacing our Shakespeare at the top of the mast with a new Morad. The Shakespeare has failed at 5 years…. Morad is just a “no brainer “ for me.

But that Shakespeare would not be a Phase III nor even a Galaxy line antenna, right?

Morad is right there at quality level with the high end lines.

[scherzoja]

Thanks for the replies,

Looks like I'll focus on the connection to the mount and how the coax is connected to the internal element or the stainless steel whip. So far, I don't see any advantage with the Phase III and Shakespeare support was vague when I asked them what improvement the Phase III would give me over the Galaxy or Classic. Answer was vague unquantifiable improvement in clarity.

I'll take a look at the other brands mentioned recently and review the earlier pages of the thread again.

Thanks again for the info.

[s/v Jedi]

Originally Posted by scherzoja

Thanks for the replies,

Looks like I'll focus on the connection to the mount and how the coax is connected to the internal element or the stainless steel whip. So far, I don't see any advantage with the Phase III and Shakespeare support was vague when I asked them what improvement the Phase III would give me over the Galaxy or Classic. Answer was vague unquantifiable improvement in clarity.

I'll take a look at the other brands mentioned recently and review the earlier pages of the thread again.

Thanks again for the info.

When the conditions are good and the antennas are new, a $50 whip will work just as good as a $400 high end antenna.

This all changes over the years of exposure to UV and humid, salty air where the high end (professional) antennas hold up great while the cheap ones start to fail, or when conditions are not good, like high wind, driving rain etc.

I feel that a good quality coax cable can last 10 years before needing replacement, so I want at least that same lifespan out of the antenna. A good quality stainless whip can do that…. for others I’ve seen the bracket mount crumble apart after a year or two.

My Galaxy Little Giant is still good. The Galaxy line is a high end line, like Phase III and Morad. Also, professional models from Glomex, AC Marine, Sailor etc. are all very good. Price is a good indication.

About materials: for fiberglass antennas, there are radiating elements inside. These can be as cheap as a stripped coax cable to high end silver plated bronze. There is no comparison between these two.