A99/Max2000 Poll and Discussion

[BammBamm]

I have used both and found the Imax a little better but the A-99 stood up to high winds better due to being shorter. I wouldn't buy either one now with living in Chicago as there is something disturbing about mounting a vertical and watching it go horizontal in a 20 mph wind. I like my Sirio S-2016 and when I move it will come with and be mounted above a beam and rotor.

 

[TonyV225]

being upside down should give it a lower TOA also

What TOA I mean hell its more like a beam with that mount! You would beable to 40 0ver S9 china with that lazer beam TOA through the earth!! LOL!!

Some may argue that it sounds and works like "GARBAGE" mounted like that!!

 

[Robb]

I have used both and found the Imax a little better but the A-99 stood up to high winds better due to being shorter. I wouldn't buy either one now with living in Chicago as there is something disturbing about mounting a vertical and watching it go horizontal in a 20 mph wind. I like my Sirio S-2016 and when I move it will come with and be mounted above a beam and rotor.

Don't know if mounting an antenna that has a ground plane above a horizontal beam will work out for you. That might seriously mess with the radiation pattern of the beam. The Imax/A99/Big Stick antennas are without ground planes and won't have that problem.

The fiberglass antennas can bend waaay over in high winds and still come back and work. One of their great strengths. I know some have busted due to high winds; but they had to be pretty severe before that happened.

 

[BOOTY MONSTER]

Don't know if mounting an antenna that has a ground plane above a horizontal beam will work out for you. That might seriously mess with the radiation pattern of the beam. The Imax/A99/Big Stick antennas are without ground planes and won't have that problem.

The fiberglass antennas can bend waaay over in high winds and still come back and work. One of their great strengths. I know some have busted due to high winds; but they had to be pretty severe before that happened.

a vector 4000 should do very well above a beam too . but from what i understand they don't do well in very high winds . and of course there's the gain master option too .

 

[137]

I guess I must have a "good" IMax, mine has been up for 7 years now and we've had some pretty bad weather here in middle TN the past 2 years and while it blows it nearly to a horizontal state at times, I still keep a fairly flat SWR and it talks like it always has. I've had around 3kw pep into it also and no issues as of yet. I have pondered putting something else up as an upgrade, just never pulled the trigger yet.

 

[W5LZ]

I've had/used an 'A99', never had an Imaxx (they weren't around then). I also don't buy many antennas, they ALL have been disappointments, mainly from believing the @#$ ads, you know?
Would I say that either the 'A99' or Imaxx antennas are 'perfect'? Nope, sure wouldn't. But they are adequate/average. For some people they can be just fine.
- 'Doc

 

[VA3ES]

many yrs ago i used to thing the A-99 was a good antenna..
( i had upgraded from the big stick )
Then i upgraded to the Imax 2000 ( it was better a bit verses A-99 )..

Then i finally Woke up and realized the antenna was a supreme part of the equation in getting out as well as receiving ..
So i Turned the Interceptor I-10K which is so far beyond better then both the A-99 & Imax 2000to the point of being in a totally different category ..

So although the A99 & Imake 2000 are so so/ ok antennas..
There are many 5/8 wave verticals that will trounce/destroy the a99 & Imax 2000..

One may not need go to spending what the Interceptor I-10 K costs
However an aluminum 5/8 wave vertical destroys a simple wire within a fiberglass housing..

A99 & Imax 2000 easily splash signals ( especially when one runs more then 20 watts into them )...
Plus the A99 & Imax 2000 do not stand up well to heavy weather
(where my Interceptor I-10K seems to laugh at even the most extreme weather )

I am not persay knocking the A99 & Imax 2000...
However there is Nothing special about them..
They are simply cheep and semi adequate antennas

I must agree 100% with everything written here. I run an Antron clone (Proton P-99) and I find it far inferior to my Hy-gain Penetrator 5/8ths. Disappointing.

 

[W5LZ]

"Interceptor I-10K which is so far beyond better then both the A-99 & Imax 2000to the point of being in a totally different category .."

You're right! It is in a different category, not the same 'type' of antenna at all. Depending on the particular situation, what your aims are, where the thing is located, the rest of your statements about this is entirely subjective.

"However an aluminum 5/8 wave vertical destroys a simple wire within a fiberglass housing.."

Sorry, that's just not true. Nothing 'magic' about an 'aluminum' antenna compared with a 'wire' antenna. Or do you think that enclosing that aluminum antenna in fiberglass would 'destroy' it's abilities? How about aluminum wire?

"A99 & Imax 2000 easily splash signals ( especially when one runs more then 20 watts into them )...
Plus the A99 & Imax 2000 do not stand up well to heavy weather
(where my Interceptor I-10K seems to laugh at even the most extreme weather )"

That 'splashing', or RFI, isn't dependent on which antenna is used, but on how it's used and placed. I'm afraid that 'Interceptor I-10K' will produce as much 'splash'/RFI as any other antenna if set up improperly. Sorry, that's just a fact.

"However there is Nothing special about them..
They are simply cheep and semi adequate antennas"

Remove that "semi" and I'd agree with you too.
- 'Doc

 

[VA3ES]

There is an inherent problem with these so-called "splatter sticks": bad TOA and commode mode currents along the feed line.

In the case of the end-fed 1/2 wave antennas (Antron 99, et al) their TOA resembles a squashed sphere, directing too much RF into neighboring houses. The other problem is incidental radiation of the coax, caused by common mode currents circulating along the feedline. All end-fed 1/2 wave antennas suffer from this. The common mode circulating currents can be choked off by using a "ground plane kit", which is in reality a common mode choke. 1/2 wave antennas neither need, nor use ground planes, but proper commercial 1/2 waves always use a common mode choke at the base. See the Cushcraft ARX2B 2-meter Ringo ranger antenna, which is two half waves in phase. The antenna sports a "ground plane" at the base, which is really a common mode choke, and is described as such in the instructions.

In the case of the Imax 2000, which is a 5/8ths wave collinear, a ground plane is mandatory. Without it, you have reactances which skew the TOA, as well as having that common mode problem too. I highly recommend a proper 1/4 wave ground plane on any Imax 2000.

 

[W5LZ]

That 'common mode current' is what makes either of those antennas work at all! You definitely don't want to get rid of it - .
As or that 'squashed" radiation pattern, what's wrong with that if it puts the signal where you want it? Most of -any- RFI will be coming from the antenna it's self, not the feed line. If radiation from the feed line ever amounts to more than a -very- slight percentage of what comes from the antenna it's self, then you are definitely doing something wrong! Wanna add a coaxial choke? Fine, do it. Make the insertion point about 9 feet or so below the feed point. I haven't seen a chock hurt an antenna system yet.
Oh well...
- 'Doc

 

[W5LZ]

That 'common mode current' is what makes either of those antennas work at all! You definitely don't want to get rid of it - .
As for that 'squashed" radiation pattern, what's wrong with that if it puts the signal where you want it? Most of -any- RFI will be coming from the antenna it's self, not the feed line. If radiation from the feed line ever amounts to more than a -very- slight percentage of what comes from the antenna it's self, then you are definitely doing something wrong! Wanna add a coaxial choke? Fine, do it. Make the insertion point about 9 feet or so below the feed point. I haven't seen a choke hurt an antenna system yet. Of course, you can certainly put one in the wrong place.
Oh well...
- 'Doc

 

[VA3ES]

That 'common mode current' is what makes either of those antennas work at all! You definitely don't want to get rid of it - .

OK - pardon my ignorance but why is that? How does common mode currents make the antennas work?

As for that 'squashed" radiation pattern, what's wrong with that if it puts the signal where you want it?

By a "squashed" pattern, I meant a squashed sphere, that concentrates most of the pattern too low, close to habitation, as opposed to a 18 - to 24 degree TOA that concentrates the pattern towards the horizon.

Most of -any- RFI will be coming from the antenna it's self, not the feed line. If radiation from the feed line ever amounts to more than a -very- slight percentage of what comes from the antenna it's self, then you are definitely doing something wrong! Wanna add a coaxial choke? Fine, do it. Make the insertion point about 9 feet or so below the feed point. I haven't seen a choke hurt an antenna system yet. Of course, you can certainly put one in the wrong place.

I agree.

 

[BammBamm]

Thanks Robb I hadn't thought of that. May have to run two lines with two antennas one on either end of the house with a switch box at the radio.

 

[BOOTY MONSTER]

i wouldn't worry too much about those little bitty 27 inch "ground elements" effecting the beam with the omni a few to several feet above it . i think they're not near big enough to act as a reflector or director on 27MHz . if the beam is electrically connected to the 2016 through the mast or common ground wire it might even benefit the 2016 by being connected to something large enough to actually be a effective ground plane on 27 MHz

all omni CB antennas produce a TOA that resemble a squashed sphere AFAIK . none produce a bubble or ball shaped dispersion pattern . typically the flatter the ball/TOA the better the line of sight performance .

and of course there's always the "antenna height dictates TOA not its wavelength" argument .

there's no good reason to not put a proper choke on the antenna IMO . i disagree with a ground-plane being a choke for common mode currents , but CMC's are caused by an inadequate ground-plane from what i understand . which brings us back to the importance of a proper ground plane under a typical antenna . my home brew 5/8 did better with four 1/4 wl elements than it did with eight 8th wl elements . i didn't bother with trying sixteen 1/16 wl elements . homerBB didn't get better or equal results using shorter than 1/4 wl ground elements on his omnis either . apparently its true that 1/2 wave and 5/8 wave antennas can work without ground elements , but that doesn't mean they work as well without them .

i got a flat tire late one night a 1/2 mile from home . i was planning on replacing the tire that blew because it has wire showing but i didn't have the money at the time (yea , i'm poor) so i just finished driving home .
apparently my truck doesn't need four good tires to work ......... but it does work better that way .

 

[Robb]

i wouldn't worry too much about those little bitty 27 inch "ground elements" effecting the beam with the omni a few to several feet above it . i think they're not near big enough to act as a reflector or director on 27MHz . if the beam is electrically connected to the 2016 through the mast or common ground wire it might even benefit the 2016 by being connected to something large enough to actually be a effective ground plane on 27 MHz

Not quite so sure about that as you are - Booty. The reason that the mast and vertical antenna doesn't affect the performance of a horizontal beam is that there is no horizontal component on them. I'm fairly certain that any ground plane will affect the beams tuning; it is a question of how much . . .
Maybe someone who knows more care to comment?