Laird FG4605 vs Comet CA712EFC

[jimlg]

I am looking to set up a GMRS base station and am looking at these two antennas.

The Laird appears to be more of a commercial antenna while the Comet appears to be
more of a hobbyist type.

My initial install will have the antenna mounted on a 10 foot pole on a chimney mount
while I erect a 70 foot tower, the GMRS antenna will be side mounted at the 55-60 foot
level.

Will the extra 2 db gain of the Comet make a noticeable difference and which of the antennas
is the better built?

I know there is a big difference in price but I want something I can install and be assured it will
be there tomorrow.

 

[mmckenna]

I only owned one Comet antenna and it was about 20-30 years ago. Never bought another.

I've had a few Laird antennas and have been happy with them for a low cost base antenna.

Not sure how much you would notice the extra 2dB of gain. That would really depend on your specific location/environment. Additional gain is great if you are out on the flatlands where the horizon is way out there -and- you are trying to talk simplex as far as you can, or are on the very fringes of repeater coverage. If you've got hills/mountains around you, the extra gain probably won't be noticed.

The way I look at things like this:
Mounting an antenna 60 feet up a tower requires climbing the tower, which is not a zero risk operation. I, personally, would not want to buy a hobby/ham grade antenna and go through all the work to mount it up that high and not have it last decades. My time is worth more to me than the extra $30-$40 for the higher grade antenna.

If it was me, I'd go with the Laird.

 

[nokones]

There is a real legitimate reason why you do not see Public Safety Agencies using Comet antennae and it is not the immediate direct cost savings factor. Use the Laird.

 

[jeepsandradios]

I will recommend the Laird all day over the ham stuff. People get worked up over a db rating that most will never see. If you want an antenna to last and not replace over and over spend the funds up front and get the Laird.

 

[jimlg]

Thanks for the recommendations, I was leaning toward the Laird from the start,
just wasn't sure if the extra 2db would make that much of a difference.

 

[KF0NYL]

I'm using the Comet CA-712EFC and it works well. But I also don't have it on a tower. As much as I like the Comet, it is not the best long term solution. This is especially true if the antenna is installed up high on a tower.

Everyone is correct that 2 dB is not going to make much difference unless you are in a fairly flat area and the antenna is above the trees around you. A 6 dB antenna will actually work better than a 9 dB antenna if you live in a hilly/mountainous area.

Think of the radiation pattern from your antenna as a ballon. The higher the gain the flatter the pattern will be. A flat pattern is good for wide open terrain but not so good with tall hills.

 

[Kiwibru]

So why the lack of confidence in the Comet line of antennas? They seem to be well built to me. Is it long term degradation that lowers their value as an initial investment for a GMRS base station? Curious because have finally decided to move further from Kenwood hand units from year 2000 and install a base station at the farm.

 

[prcguy]

I have a Comet CA-712EFC and its a very good antenna for GMRS and not designed like the typical Comet ham antenna. Its built like a Stationmaster with a bunch of 1/2 wavelength coax sections soldered in and out of phase instead of the bent up copper wire radiators in a typical Comet. If the radome junction is sealed well during assembly it should provide long live a good performance for a very fair price.

There have been some comments on using it for repeater service where over time the braid of the coax may tarnish and create IMD problems in full duplex service but I'm not sure that's been proven.

I posted about the Comet CA-712EFC construction in another thread and poached the picture to show how its made compared to a typical Comet ham antenna.

 

[ladn]

The Laird appears to be more of a commercial antenna

Get the Laird (or a Larsen).
As others have stated, Comet, and other "hobbyist" brands, are seldomly seen in professional/commercial applications.

 

[Kiwibru]

Wow. The Comet CA-712EFC is one long (tall antenna) at 10ft. +. I was looking at the Comet CA-GMRS which is only 4.5 ft. tall as a starting setup. I have a mast mounted on the east end eave of the house that used to support a TV antenna and it is already six feet above the peak of the roof. Just going to use that for the mounting. Re-do the grounding feed wires, get some high quality coax and build it out. Laird looks nice but a lot more $. Probably, like anything else, you get what you pay for. Hmmm. Thanks for the feed back.

 

[mmckenna]

Laird looks nice but a lot more $. Probably, like anything else, you get what you pay for. Hmmm. Thanks for the feed back.

Shop around. I found them pretty close to the price of the Comet.

 

[AK9R]

I have a Comet CA-712EFC and its a very good antenna for GMRS and not designed like the typical Comet ham antenna. Its built like a Stationmaster with a bunch of 1/2 wavelength coax sections soldered in and out of phase instead of the bent up copper wire radiators in a typical Comet. If the radome junction is sealed well during assembly it should provide long live a good performance for a very fair price.

How does the soldering look? I believe that Commander Technologies took over the Phelps Dodge Stationmaster design, but I have heard scattered reports of bad solder joints in some Commander Technologies antennas.

Any capacitors in the Comet antenna.

Looks like the Comet radome is two pieces. Does it look like the seal well at the joint?

 

[KF0NYL]

All Comet antennas have rubber seals at the radome joints. I can't say how well they work since I still wrap the joints just like I wrap all of my coax connections.

 

[prcguy]

How does the soldering look? I believe that Commander Technologies took over the Phelps Dodge Stationmaster design, but I have heard scattered reports of bad solder joints in some Commander Technologies antennas.

Any capacitors in the Comet antenna.

Looks like the Comet radome is two pieces. Does it look like the seal well at the joint?

The soldering looks fine and I would have to dissassmble the entire antenna to see if there are any components near the feed. I doubt it as they are not required for this type design. I see in my picture the solder connections look bare and I'll revisit that. If they are and I can take the bottom radome off I will cover each solder junction with hot glue heat shrink. That would seal every connection and reduce any potential corrosion of the coax braid.

 

[K9KLC]

Looks like the Comet radome is two pieces. Does it look like the seal well at the joint?

way better than the diamond equivalent antenna's do.

 

[jimlg]

I have a Comet CA-712EFC and its a very good antenna for GMRS and not designed like the typical Comet ham antenna. Its built like a Stationmaster with a bunch of 1/2 wavelength coax sections soldered in and out of phase instead of the bent up copper wire radiators in a typical Comet. If the radome junction is sealed well during assembly it should provide long live a good performance for a very fair price.

There have been some comments on using it for repeater service where over time the braid of the coax may tarnish and create IMD problems in full duplex service but I'm not sure that's been proven.

I posted about the Comet CA-712EFC construction in another thread and poached the picture to show how its made compared to a typical Comet ham antenna.

How much flex does the Comet CA-712EFC have in a high wind?
I would think if you were side mounting the antenna on a tower you
would want to have a non metallic mount at the top of the antenna to
keep it from flexing.

 

[prcguy]

How much flex does the Comet CA-712EFC have in a high wind?
I would think if you were side mounting the antenna on a tower you
would want to have a non metallic mount at the top of the antenna to
keep it from flexing.

Its pretty stiff and I there is no need for bracing where I live. I would not use this on a 5k ft mountain top but it seems fine for home use.

 

[Kiwibru]

That wind is a big issue for this geographic location. We typically have winter storms blowing in from the S to SW with winds in the 40-65 mph range. If we get a northeast arctic blow from interior of Canada we can have 85-100 mph range but thank goodness those NE outflow events are rare. An antenna this high would be an interesting match for those conditions, thus the 4.5ft. CA-GMRS seems a better option than most I have seen. There may be others so if you have any recommendations I am all eyes.

 

[KF0NYL]

I can say that the CA-712EFC and Comet GP-9 has withstood unto 60 mph shear winds here in central Missouri. Granted we do not get those kinds of winds all of the time. The CA-712EFC is mounted to a 40" tall satellite dish j mount at the peak of my roof. So the base of the CA-712EFC is about 18 feet above the ground. On the other end of the house is my Comet GP-9 and it is on a a 1 5/8" fence post mast. The base of the GP-9 is 22 feet above the ground. I also have a 6m-20m cobweb antenna on a j mount and 8 foot 1 /58" fence post which puts the antenna at 24 feet above ground. The masts for the GP-9 and cobweb are guyed with Matron guy rope. I didn't guy the CA-712EFC.

Both antennas have only been up since October 2023. But so far they have held up. I did wrap all of the connection joints on both so I don't have to worry about water intrusion. Both are easy to access while standing on the roof.

I would personally want a better commercial grade antenna if I was putting them up on a 50 foot or higher tower. I can't climb towers anymore and don't want to wait for others to help.

 

[prcguy]

I can say that the CA-712EFC and Comet GP-9 has withstood unto 60 mph shear winds here in central Missouri. Granted we do not get those kinds of winds all of the time. The CA-712EFC is mounted to a 40" tall satellite dish j mount at the peak of my roof. So the base of the CA-712EFC is about 18 feet above the ground. On the other end of the house is my Comet GP-9 and it is on a a 1 5/8" fence post mast. The base of the GP-9 is 22 feet above the ground. I also have a 6m-20m cobweb antenna on a j mount and 8 foot 1 /58" fence post which puts the antenna at 24 feet above ground. The masts for the GP-9 and cobweb are guyed with Matron guy rope. I didn't guy the CA-712EFC.

Both antennas have only been up since October 2023. But so far they have held up. I did wrap all of the connection joints on both so I don't have to worry about water intrusion. Both are easy to access while standing on the roof.

I would personally want a better commercial grade antenna if I was putting them up on a 50 foot or higher tower. I can't climb towers anymore and don't want to wait for others to help.

The Comet should handle 100mhp winds with some ice since it’s only 10ft tall. It’s the big 21ft jobs that snap in half with winds and ice. And more gain is more better unless you’re snuggled up against a 1000ft or higher hill and the antenna is on top of the hill.