Comet SS-460SB NMO or Larsen NMO-2/70SH??? Is One "Better?"

[Robert Bills]

Ok, I’ve over-analyzed my choice of antennas to the point of paralysis. :drool:

Please help me choose which one of these two dual band antennas for my Yaesu FT-90R. I need to get this done.




Comet SS-460SB NMO 18” closed coil with spring, black [$43.95]

Published specs:


146MHz 1/4 wave 2.15dBi
446MHz 5/8 wave 3.8dBi
VSWR: 1.5:1 or less
Max Power: 60W
Length: 18"
Connector: NMO


Larsen NMO-2/70SH 19” closed coil with spring, stainless whip [$49.95]

Published Specs:


VHF: ¼ wave 2.14 dBi
UHF: ¾ wave 4 dBi
VSWR: 1.5:1 (see below)
Max Power: 200W
Length: 19”
Connector: NMO
Also: “BANDWIDTH @ 1.5 VHF: 10% / UHF: 10% BANDWIDTH @ 2.0 VHF: 15% / UHF: 17% COIL VHF: 146 MHz / UHF: 445 MHz . . . Black/Stainless WHIP .100 enclosed coil . . . .”


These antennas appear to be of nearly identical height and rated performance at approximately the same price. However, the additional information provided for the Larsen NMO 2/70SH regarding bandwidth (which I do not pretend to understand), and its greater power capacity, makes me wonder whether the Larsen might have greater bandwidth than the Comet or be a superior product.


Does anyone know if there is much or any real world difference between the two? Experience with either or both?


If the Larsen is “better” for an offroading appliance operator like me, who sometimes tries to listen to frequencies at the edges of the bands but for the most part use my radio to listen to the real Hams and for trail communications, then the Larsen is the antenna I will buy. If however, they work the same and are built the same, I am leaning toward the Comet if for no other reason than it is black and won’t glint in the sun or be as noticeable as a stainless whip.

Thanks for the help.

 

[HenryJ]

Larsen. Why?
I have owned a few and they have been good. Not the model you are looking at specifically though.

Here is the reason for my vote: Larsen- http://www.eham.net/reviews/detail/434 Comet- http://www.eham.net/reviews/detail/11269

Larsen has the edge, IMO. Currently running dual 1/4 wave Larsen whips using a duplexer.

 

[4x4mike]

Now it's time for me to add to your thread.

The SS-460 was also on my short list. It had the dbi numbers, price and the added spring caught my interest.

Between the 2 listed they seem very similar, kind of like a same thing different brand. I own Larsens and Comets and they are great antennas in my opinion. If I were you, and this is what I've done, is get a few antennas. Most of my friends stick to 2m as they have mono band radios. A 1/4 wave NMO antenna can be had for cheap. They put up with tree branches, parking garages, etc. 70cm around me is pretty dead but nice to have in Southern CA and Oregon for the WINsystem. My 70cm use is for my crossband feature.

Get one of the ones you asked about and one of these for everyday use: http://www.theantennafarm.com/catalog/laird-technologies-qw144-718.html

 

[DaveInDenver]

They both should have similar 2m gain & bandwidth, that's just a function of the construction since they are both just 1/4 wavelength. The 70cm performance might be a little different because the Larsen is 3/4 wavelength and the Comet claims to be 5/8. If that's true they the radiation patterns will be different, although gain in the main lobe would be similar. My guess is it comes down to personal preference really, which seems better built, looks better, etc.

I never had any trouble with the NMO2/70SH I have, it did what it was supposed to, no drama. One of first dual band mobiles I had was a Comet, which began to fail at the fold-over feature. That doesn't apply here AFAIK. Comet and Diamond antennas also tend to have fairly fragile coils, small gauge winding wire mainly. So high power tends to ruin them quicker. That's why I originally selected the open coil Larsen over the enclosed one, no wire to short or melt.

One thing to mention is Larsen will sell you replacement parts, they don't change things randomly. Crack a base or coil, you can replace just the base or coil. Need a new whip, you can get just a whip. Also parts are universal, so all the whips are the same diameter, the base seals are all the same, etc. For example my CB antenna is a NMO27 and the rubber seal is the same with the Larsen NMO cap, so I never misplace the seal swapping between the two.

BTW, I wholeheartedly second The Antenna Farm. Prices are reasonable, small operation, nice people.

Larsen has the edge, IMO. Currently running dual 1/4 wave Larsen whips using a duplexer.

That's what I do, too. Although I have converted to STI-CO whips (although only partially in this photo with a Larsen UHF still).

 

[HenryJ]

All this talk and I did a little testing. Decided to try a 5/8 whip on 2m for a while.

 

[Frdmskr]

You will never go wrong with a properly installed Larson. The imports have always fallen apart on me.


Sent from my iPhone using Tapatalk

 

[4RunAmok]

Comets are great if you have little ground plane to work with, since they're more ground neutral than their Larsen counterparts. The problem with Comets and Diamond antennas of this type is they are very rigid, and for offroad use (low hanging branches and other snaggers) you can really mess up one of these antennas.

The Larsens are more forgiving, and will take being whipped around just fine.

Now since you're using an NMO mount, I'm assuming rooftop, you have a great surface area to provide the ground plane the Larsen will need.

You can also get the Larsen in black. That's the version I have. I also chose to go without a spring, and even in the lowest of branches overhead, I've never needed a spring, and my roof has never bent as a result.

 

[Robert Bills]

. . . since you're using an NMO mount, I'm assuming rooftop, you have a great surface area to provide the ground plane the Larsen will need.

Not a rooftop mount - NMO mount on tab welded to roof rack, which is grounded to body/frame. [Entire roof is covered by rack - no place to drill.] Does this change your opinion in any way regarding Larsen NMO-2/70SH v. Comet SS-460NMO?

You can also get the Larsen in black. That's the version I have. I also chose to go without a spring, and even in the lowest of branches overhead, I've never needed a spring, and my roof has never bent as a result.

Are you referring to the 19" Larsen NMO-2/70SH in black or some other Larsen antenna? The only 19" Larsen I am aware of comes with a spring, stainless whip and black coil.

 

[DaveInDenver]

With respect to the counterpoise on your roof rack tab, the NMO2/70SH and SS-460SB will act basically identically. You might see a slightly difference in the SWR on 70cm with the Larsen being electrically a 3/4 wavelength compared to the 5/8 wavelength of the Comet. I might expect that the Comet would exhibit just a bit more ground plane independence while tuning. But if the 2m side tunes up then the 70cm will as well, since both will need 2m ground plane to work well and by default you will then have more than enough for 70cm.

There's no reason that a grounded roof rack can't work in this case, although being able to tune to a low SWR does not guarantee that your radiation pattern will be perfect. It might tend to distort in the direction of your ground plane.

 

[SARguru]

I got an ss460sb in December to replace my forth broken comet b10. I have them mounted thru the roof of my suburban the 4 b10 either the whip bent or the coil broke where the whip connects to the coil from hiting branches and such.. The 460sb has on several occasions now survived the height bar at parkades, I'll be getting a second 460sb to replace the latest damaged b-10.

If you are using a braket for the nmo put caulking or some type of goo on the bottom wire side of your mount to protect the wire from corrosion. The Larsen antennas took a beating its the wires i had to replace every year or so.

Nic

 

[Robert Bills]

. . . [f]f you are using a bracket for the NMO put caulking or some type of goo on the bottom wire side of your mount to protect the wire from corrosion. The Larsen antennas took a beating its the wires i had to replace every year or so.

This is the Breedlove NMO mount I will be using (and the one he recommended for a roof rack tab mount), which hopefully should address any strength or corrosion issues:

 

[Robert Bills]

I just ordered a Larsen NMO-2/70SH from The Antenna Farm.

Thanks for the help in making my choice and for the lead for the vendor.

 

[DetroitDarin]

You will never go wrong with a properly installed Larson. The imports have always fallen apart on me.


Sent from my iPhone using Tapatalk

Just found this funny - imports have failed him; sent from his (imported) iPhone

 

[Frdmskr]

Oh the irony of life

 

[DetroitDarin]

:beers: to ya!