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KC9VFO
07-13-2012, 09:11 PM
http://img.photobucket.com/albums/v609/Thirstyguy/003-5.jpg




My friend gave me an IMAX 2000 to see if I wanted to use it for 10 meters. After some inspection I decided this was the best option.

WB2WIK
07-13-2012, 09:20 PM
I'd clamp on a reel at the bottom and some line guides along the length, add a nice handle and bingo.

"Whatcha castin' there, son?"

"IMAX 2000."

KC7YRA
07-13-2012, 09:21 PM
LOL. When I read the title of this thread, I was thinking "in the trash". Then I clicked in and saw the pic. LOL.

At least pull the aluminum off and recycle it.

Brad

N3JBH
07-13-2012, 09:22 PM
Oh boy :rolleyes: this should get some response. Some folks think there darn great antenna's. Personally i tore it apart just to see what made it tick and salvage what i thought be useful like the mounting plate.

WB2WIK
07-13-2012, 09:28 PM
There used to be some really great all-aluminum CB antennas in the good old days. Some law made them illegal years ago (electric shock hazard prevention stuff -- really silly). But I see some are coming back now as 10m amateur antennas, which are okay as aluminum.

The old Antenna Specialists Super Magnum and such were very good. Sure a lot better than the Solarcon, IMAX, etc. At least they're making a comeback as ham antennas.

W9GB
07-13-2012, 10:00 PM
My friend gave me an IMAX 2000 to see if I wanted to use it for 10 meters.
What is the best wasy to mount it?

You are missing the TWO Mast (Saddle) clamps - aluminum and stainless steel clamp will cost you about $6 to $10 each.
Get out your TAPE MEASURE , take measurements, andthen select appropriate U-Bolt.
DX Engineering has a wide selection for this type of repair.
http://www.dxengineering.com/

You then need a mast, at least 1-1/4 inch OD -- which is same size as TV antenna mast.

w9gb

KC9VFO
07-13-2012, 10:02 PM
Actually I robbed the U bolts and threw them in my junk drawer. :)

K8JD
07-13-2012, 10:16 PM
It would have been a good antenna to work local 10M FM repeaters. If you can set your A/B split freq to do 100 kHz split and switch the rig's mode to FM.

KC7YRA
07-14-2012, 12:57 AM
There used to be some really great all-aluminum CB antennas in the good old days. Some law made them illegal years ago (electric shock hazard prevention stuff -- really silly). But I see some are coming back now as 10m amateur antennas, which are okay as aluminum.

The old Antenna Specialists Super Magnum and such were very good. Sure a lot better than the Solarcon, IMAX, etc. At least they're making a comeback as ham antennas.

Exactly. I would love an old, all aluminum vertical that I could put onto 10. These fiberglass jobbers just don't hold up here. Poor construction and lackluster performance.

Brad

N4BWD
07-14-2012, 07:18 PM
Send it to me! I want it!
N4BWD

KI6USW
07-14-2012, 07:57 PM
Lets just compare a Hustler 4BTV (10, 15, 20, & 40M) to the Imax 2000 (10, 12, 15, & 17m):

Lossy traps in the Hustler and Imax? YES

Cost about the same (~$120)? YES

Can work four different bands? YES

Both can be ground-mounted or elevated? YES

Do they both require radials for best performance? YES

Both benefit from using an antenna tuner? YES

Do they both belong in the garbage? YES and NO.

Depends what fits your needs, pocketbook, and location. Sure there are better antennas. But if one considers the cost, what you get for your money, and ease of installation - I think there isn't that much difference between the two. Except for the bands used.

KC7YRA
07-14-2012, 08:06 PM
Well, the Imax can work 4 bands with a tuner. Whereas the 4BTV is resonant.

Other than that, the construction techniques are the big divider in both of those. Thin fiberglass shell or aluminum tubing.

Brad

KI6USW
07-14-2012, 08:50 PM
Well, the Imax can work 4 bands with a tuner. Whereas the 4BTV is resonant.

Other than that, the construction techniques are the big divider in both of those. Thin fiberglass shell or aluminum tubing.

Brad
Yup.

One other thing. If one uses/adds the proper radial lengths for 20m and 6m; the Imax can do those too. However, that evidence is second-hand. The anecdotal evidence is found in the eHam reviews. But I have used the Imax on all of the bands I mentioned. Made some long-path skip on 17m to Japan and Ireland from here in CA though - using a tuner to clean up the small mismatch. The other three bands didn't need it.

The 4BTV - I dunno . . .

K2HAT
07-14-2012, 09:33 PM
I have an IMAX 2000 here, that with an external tuner, I have used it on 40m, nope not great for 40m,
but when it was the only antenna I had for HF it was better than none.

Works pretty darn good for 10-17m, it helped me to get my WAS and DXCC. ;)

97698

http://files.qrz.com/t/k2hat/DSCN5052_Large_.JPG

73 K2HAT Lee :)

WB2WIK
07-15-2012, 12:24 AM
I have an IMAX 2000 here, that with an external tuner, I have used it on 40m, nope not great for 40m,
but when it was the only antenna I had for HF it was better than none.

Works pretty darn good for 10-17m, it helped me to get my WAS and DXCC. ;)

97698

http://files.qrz.com/t/k2hat/DSCN5052_Large_.JPG

73 K2HAT Lee :)

Good job, Lee. Testimony to probably good operating, good timing, and knowing what band to be on when -- all part of ham radio!

I like that approach, a lot.

I've worked DXCC in less than 8 hours during a contest, and worked DXCC even on 80 meters (took 36 hours, though) in a contest, using a lot of big antennas and kilowatts. Not much of an accomplishment, really. Running 100W in casual operation with a small antenna it's a much better accomplishment, and you learn a lot along the way.

KA1MDA
07-15-2012, 04:41 AM
Lets just compare a Hustler 4BTV (10, 15, 20, & 40M) to the Imax 2000 (10, 12, 15, & 17m):

Lossy traps in the Hustler and Imax? YES

That is not an accurate comparison. A Hustler 4BTV is RESONANT on 10, 15, 20, and 40 meters. The Imax 2000's radiating element is RESONANT only on 10 OR 11 meters. As such, the Imax is a 1 band antenna vs the Hustler being a true 4 band antenna, although you can fool yourself into thinking the Imax is a multiband antenna by using a tuner.

Traps are not automatically "lossy". That's a result of advertising hype by the manufacturers of antennas which do not use traps. In fact, there is far more loss incurred using a single band antenna with a tuner in the shack than there is in using a multiband trap vertical with no tuner. Contrary to your statement, the Imax 2000 has no traps- it has a single, very lossy matching network in the base to fool the radio into thinking the antenna is resonant on more than 1 band. Such a matching network, similar to that used in a Comet CH250B, can EASILY create upto 10 dB of loss.

Another issue which you do not address is radiation angle, or vertical take-off angle. A trap vertical will have a much lower take off angle on all the bands it covers based on the fact that each band sees a quarter wavelength long antenna. An antenna like the Imax will only have a low take off angle on 1 band (10 or 11 meters). As the frequency of operation goes down, the radiation angle will increase, due to the antenna being electrically shorter.

PA5COR
07-15-2012, 09:16 AM
For 10 meters it's a 5/8 antenna, for 15 it is a 1/2 wave antenna, 12 and 17 are close to the 10 and 15 meter band for that wideband coupling to work.
Even a 1/2 wave end fed antenna has a low angle of radiation as does the 5/8 antenna.
Whatever the story's tell, i worked on 10/12/15/17 worldwide with 100 watts in it, and all continents.
The other antenna's Fritzel FD-4 and inverted L of 77 feet with autotuner at the feedpoint.
Comparing the Imax 2000 with 5 meter long radials on the roof with the FD-4 at 45 feet up the lower angle mostly took care of a better signal on 10/17.
That "lossy"network could handle 1 KW fine on 17 meters, if there had been 10 dB loss i'm sure it would have burned out with that power, some have put in even more power to it....

It handled that power on all bands from 10 down to 17, i don't use it for 20, there the inverted L works better or the FD-4 OCF.
For a free, given to me, antenna it does quite fine, thank you.

I don't look down on the antenna never work 11 meters but if it works on my bands, it is a good thing to have.
I got mine for free, and it's on the roof for 9 years now, withstood all storms, and at 35 feet above ground it gave excellent reports from all over the world, what more can you ask from a free antenna?
My radials are just 4 wires of 5 meter length that go from the baseplate laying on the roof in a 45 degree angle.

Will there be better antenna's? yes undoubtly, but this was free, fits on my roof and does work all over the world.

KC9VFO
07-15-2012, 01:35 PM
There used to be some really great all-aluminum CB antennas in the good old days. Some law made them illegal years ago (electric shock hazard prevention stuff -- really silly). But I see some are coming back now as 10m amateur antennas, which are okay as aluminum.

The old Antenna Specialists Super Magnum and such were very good. Sure a lot better than the Solarcon, IMAX, etc. At least they're making a comeback as ham antennas.

I have been carrying around an old Hustler JR 27 aluminum 5/8s wave cb antenna for the last 30 yrs, but they are uuuuugggglllyy. Probably work good on 10 though. I have an Old Yaesu ft101 I can use also. I am leaning towards a ridged dipole for 10. Been too hot and dry here for any antenna work, all our time is spent watering bushes and gardens etc lately.

M0GVZ
07-15-2012, 02:35 PM
My friend gave me an IMAX 2000 to see if I wanted to use it for 10 meters. After some inspection I decided this was the best option.

Why did you do that? They work very well on 10m. I used an Imax 2000 as my sole antenna in the October 2011 CQ-WW-DX contest and made over 700 contacts in 24hrs on 5 continents with it using no more than 100W.

KC9VFO
07-15-2012, 02:47 PM
Why did you do that? They work very well on 10m. I used an Imax 2000 as my sole antenna in the October 2011 CQ-WW-DX contest and made over 700 contacts in 24hrs on 5 continents with it using no more than 100W.

Why? Because it is a piece of junk. The fiberglass is cracked all the way through where it is epoxied in the metal connectors, lucky if it would stand up on its own. The guy who gave it to me said he only had it for 5 yrs. Imax 2000s belong in the garbage in my view. Your mileage may differ.

W9PSK
07-15-2012, 02:48 PM
I just love all the clever ways hams come up with to slam anything and everything related to CB. It must be nice to be soooo much better than others.

K2HAT
07-15-2012, 03:31 PM
Why? Because it is a piece of junk. The fiberglass is cracked all the way through where it is epoxied in the metal connectors, lucky if it would stand up on its own. The guy who gave it to me said he only had it for 5 yrs. Imax 2000s belong in the garbage in my view. Your mileage may differ.

Wow only 5 years and it is in bad shape? Maybe the newer ones have quality control issues.?

Mine has been up at this location since August 1999, took it down 2 years ago, and replaced the RG-213 with Generic lmr, low loss 400.
I also removed the add on radial kit, as it did not seem to help, and only added to the ice load, when we have ice storms.
I am using some ground radials.

Any antenna is better than none. Resonant would be the best, but, I don't have much property.
W6AM had the best antenna setup I ever heard of.


Old photo of rear of house, before vinyl siding, and showing the old short 2m/440 vertical.
If you look close you can see the ladder line feeding the G5RV dipole.

97776
http://fox302.com/userdata/k2hat/files/K2HAT/DSCN3179Medium.JPG

73 K2HAT Lee

KC9VFO
07-15-2012, 03:49 PM
Wow only 5 years and it is in bad shape? Maybe the newer ones have quality control issues.?

Mine has been up at this location since August 1999, took it down 2 years ago, and replaced the RG-213 with Generic lmr, low loss 400.
I also removed the add on radial kit, as it did not seem to help, and only added to the ice load, when we have ice storms.
I am using some ground radials.


73 K2HAT Lee

I am glad you have good luck with your antenna. We probably have the same weather and wind conditions, this Imax just didn't hold up. Ragged Imax with an empty garbage can provided me with a photo I couldn't resist. At least KC7YRA thought it was humorous :)

KA1MDA
07-16-2012, 04:01 AM
For 10 meters it's a 5/8 antenna, for 15 it is a 1/2 wave antenna, 12 and 17 are close to the 10 and 15 meter band for that wideband coupling to work.

WIDEBAND COUPLING = HIGH LOSS! The Imax 2000's radiating element may be close to an electrical half wavelength long on 15 meters, but a 1/2 wl end fed vertical has a feedpoint impedance in the range of thousands of ohms. The only reason the antenna loads up as is due to the extremely lossy "matching" network in the base. And even it the radiating element length was close to being a 5/8 wave antenna on 10 meters (it's about 4 feet too long), it would require a ground plane to operate efficiently, which it does not have. The Imax 2000 (like the Comet CH250B) is nothong more than an over rated smoke and mirrors "magic" antenna. It works equally poorly on all the bands it supposedly covers.

KC7YRA
07-16-2012, 04:38 AM
I just love all the clever ways hams come up with to slam anything and everything related to CB. It must be nice to be soooo much better than others.

I just love the way folks jump all over anything CB related, even if it is crap, and protect it as if it were a sacred cow. It must be soooooo gratifying to speak up for a service incapable of standing on its own merits or the substandard equipment so commonly affiliated with it.

Brad

PA5COR
07-16-2012, 08:19 AM
Read my full post again, i have 4 radials of 5 meter long or 17 feet length each on the roof.

Again, if that wideband coupling causes 10 dB loss as you stated, explain please, why that coupling doesn't burn out running 1 KW on 10 - 17 meters, some even put 2 KW in it on those frequencies.
If the coupling has 10 dB loss with 2 KW there would be 1800 watts loss in there transferred to heat and burn up the coupling, nothing of that happens.

Meaning more power is transferred to the antenna, as you stated...
The comet is a lot smaller and sold as a all band antenna even for lower frequencies.
No wonder the efficiency is lots lower there, and the coupling there is made with ferrite beds around copper tubing, i made one myself just for fun and testing, and it didn't come close to the Imax 2000 on 10 - 17.
Leaving the Imax 2000 at the original frequency for 11 meters lets is be smack right between 10-12 meter and be resonant on 15 as 1/2 wave end fed, the 5/8 is also an end fed high resistance point for what the matching network is made.
Not using ferrite but aircores makes it more broadbanded, and lets the network do it's task from 17 -10.
Just repeating what others once stated doesn't make it true, try to understand the antenna and how it works on each band.

I had other antenna's here on the roof equal length and with traps as vertical, the Imax without traps works just as fine.
It has been up here for 9+ years in all storms we had, never let me down, not bad for a free gift.
No lossy traps, that are water ingress prone, or break from the wind too, and these antenna's have matching networks too at the feedpoint.......with all problems rising from that.

The best test is a side by side comparison and that is exactly what i did, even with a copy of the CHA 250, Cushcraft R5 for 10/20 MHz...
I rather test and measure antenna's as parotting what other people assume.
Fact is with 100 watts i worked all continents on 10-17 with the antenna with excellent reports.
And it has no problem using the Heathkit SB-1000 with new 3-500ZG on it even on extended long qso's.
That is reality.





WIDEBAND COUPLING = HIGH LOSS! The Imax 2000's radiating element may be close to an electrical half wavelength long on 15 meters, but a 1/2 wl end fed vertical has a feedpoint impedance in the range of thousands of ohms. The only reason the antenna loads up as is due to the extremely lossy "matching" network in the base. And even it the radiating element length was close to being a 5/8 wave antenna on 10 meters (it's about 4 feet too long), it would require a ground plane to operate efficiently, which it does not have. The Imax 2000 (like the Comet CH250B) is nothong more than an over rated smoke and mirrors "magic" antenna. It works equally poorly on all the bands it supposedly covers.

W9PSK
07-16-2012, 10:16 AM
I just love the way folks jump all over anything CB related, even if it is crap, and protect it as if it were a sacred cow. It must be soooooo gratifying to speak up for a service incapable of standing on its own merits or the substandard equipment so commonly affiliated with it.

Brad

Yes, we know, O Great Discerner of All Things Radiopure. We bow at thy magnificence and splendor. Thy forgiveness I beg for speaking in defense of such dirty, disgusting, and unworthy a service. Thou hast opened mine eyes to the superiority thy license has granted thee. I see thy greatness has resulted in thy exaltation to moderator. Today a moderator, tomorrow King of Radioland! :D

BTW, when did you become a mod? I don't remember seeing that before. Does this mean I can't disagree with you now for fear of being banned? (Ok, ok, just messin with you on that part.)

KC7YRA
07-16-2012, 02:01 PM
Yes, we know, O Great Discerner of All Things Radiopure. We bow at thy magnificence and splendor. Thy forgiveness I beg for speaking in defense of such dirty, disgusting, and unworthy a service. Thou hast opened mine eyes to the superiority thy license has granted thee. I see thy greatness has resulted in thy exaltation to moderator. Today a moderator, tomorrow King of Radioland! :D

BTW, when did you become a mod? I don't remember seeing that before. Does this mean I can't disagree with you now for fear of being banned? (Ok, ok, just messin with you on that part.)

LOL, Nice.

No no, disagree away. What kind of forum would it be if nobody could disagree with me? :)

Brad

KB4QAA
07-17-2012, 12:06 AM
Gee, I thought the best way to mount it would be with a hammer and nails! :)

KD8GFC
07-17-2012, 08:27 PM
Imax 2000 and the a99 are good antennas i dont care what anybody says I have worked the globe on my a99 with less than 100 watts output. I have used many antennas and the a99 performs just as well. The only reason some hams knock it is because it was made for 11 meter i cut mine for 10 and it matches and workes great DX and local. Are there better antennas yes but for 49.00 you cant go wrong.

EA4TA
07-18-2012, 02:38 AM
I am aiming for DXCC in as much bands as I can with my old CB antenna. A shack tunner. A new log. And 100 watts.

It is an aluminium Tagra F3 with stock radials, that was installed 25 years ago in a 5 meters mast at the roof with no guying, and still looks like new.

In less than a year I've worked +100 countries SSB in 20, 17, 15, 12 and 10.

45 in 40 meters (no, it is not that good here). 10 in 80 meters (it is a noise nightmare there). And 1 in 160 meters for the fun of it (I really celebreted this one).

The antenna excells at 10, 12 and 17. It really works at the pile-ups, and got me some WWDX/WPX 10 m. monoband contest diplomas in some years ago.

Remember. 25 years!. Not all the better performing vertical antennas last that long. (I look at the roofs and they soon look like abandoned and most of them bent). Mine is mechanically sound, and so much fun!.

Enjoy what you have and ride the waves!.

73,
EA4TA

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