Base New Imax wont tune 11m....this sucks

[Big Kahuna]

I have the same antenna as of a year ago and was getting high s w r readings as well. I got a new antenna and new coax so at this point I had no idea what my issue was originally until I started to research and find out that the antenna in fact was shortened. I have been reading online about people adding an extension to the top third of the antenna, and another post on Facebook showing where a guy put a choke in. I just took my Max 2000 antenna down recently and I am trying to figure out where to go with it. People have told me within a fairly close to stands that I sound very far out. I seem to get it better with my Wilson 1000 mobile antenna than the Max 2000.

Couple of questions for you.

- When did you purchase your current Imax 2000?
- Can you measure the length of your Imax fully assembled?
- What is your install, how is it mounted and how high?
- Is your antenna easily accessible?
- What equipment are you using to measure your SWR?

I may be able to assist you with your antenna but need this info first.

 

[heffer]

I purchased this just over a year ago. I just measured each section of the antenna this evening. I will attach pics. The antenna is fairly accessible for me to push up and down and work on. I use a radio shack and a couple of dosey pm 2001 meters. Measurements are:
Top- 94 3/4 inch
Middle- 92 5/16 inch
Bottom- 94 3/4 inch
(I did not measure it all together with lock washers complete)

My antenna is at 36 to 38 feet at the bottom connector

 

[Big Kahuna]

I purchased this just over a year ago. I just measured each section of the antenna this evening. I will attach pics. The antenna is fairly accessible for me to push up and down and work on. I use a radio shack and a couple of dosey pm 2001 meters. Measurements are:
Top- 94 3/4 inch
Middle- 92 5/16 inch
Bottom- 94 3/4 inch
(I did not measure it all together with lock washers complete)

My antenna is at 36 to 38 feet at the bottom connector

Ok so it does sound like you have the version that is 4 inches shorter. The statement that your Wilson 1000 gets out better than your Max 2000 worries me though - regardless of the antenna length issue even at 1.7 or 2.0 SWR your Max2000 at 36 feet should easily outdo your Wilson antenna.

 

[heffer]

ya that worried me to. I just put up my old antron the other weekend..... although i have not tried it since i put it up. Perhaps this sunday i will have some time. Now i did talk to a guy on facebook and he mentioned he lengthened the end of the whip to fix his issue. On top of this, the maker of solarcon antenna does know that these antennas are short and not designed now for the cb freqs. I did email road pro and they replied saying:

Hi Mike ~
These will be available for purchase sometime soon.
Thank you !

Take that for what it is i guess..... As to a time frame; i have no idea. I have attached a pic of the prototype that is currently being tested and the extension that will be available "sometime soon".......

 

[S&W357]

Looks official...picture does anyway.

 

[Big Kahuna]

I tested the extension and it does work. My only concern is if it will be a weak point long term but only time will tell. I was happy to see they are working to solve the issue.

 

[Eldorado828]

I tested the extension and it does work. My only concern is if it will be a weak point long term but only time will tell. I was happy to see they are working to solve the issue.

So the extension is now available?

 

[Big Kahuna]

So the extension is now available?

No they sent me one during testing to see how it worked in lowering the SWR with my antenna. I'm guessing it will roll out shortly if they had good results all around.

 

[357]

I tested the antenna with a 102" whip as the top section today

It added 9" to the length (over the stock top section) but I actually saw worse SWR in the CB band and the resonant frequency was still up at 28.000MHz.

Ch 1 - 1.78
Ch 40 - 1.46

The lowest SWR with the factory top section was 1.385 at CH 40 so with this current version adding a 102" whip did not do anything of value. This is could be due to the diameter of the 102" being much larger than the internal copper wire.

It's interesting that adding the 102" whip making the antenna 9" longer did worse than NightThumper's experiment of adding 10" with the spacer between the top and middle sections or my experiment of adding 12" of copper wire to the factory top section.

Sorry I didnt follow this thread but that is what I found, the SS whip made it worse so I gave up.
Cost me a $120 to buy and ship that stupid whip

The 102" whip made the swr worse.
This thing is done. I put the factory whip back on.


This isn't the Imax I remember. I dont know what they did but its the 35th time I've had this thing down.
A flat match on any frequency is impossible except like 23mhz.
Even with a 1.35 swr people cant hear me. at 1.5 with the rings somewhere else it seems to get out better.

My buddy has one and its a flat match on 40 and 1.1 on ch 1.
Another guy has a antron 99 with a flat match across the band.

This horse is dead.

Heres some measurements from the bottom of the mounting plate, and a cheap plastic insulator thats seen better days.

total length with 102 whip: 291.5"
total with stock whip: 285.5" 23.79 feet

Expected lengh: 289" 24.08 feet



View attachment 32840 View attachment 32841 View attachment 32842 View attachment 32843 View attachment 32844 View attachment 32845 View attachment 32846

 

[357]

I tested the extension and it does work. My only concern is if it will be a weak point long term but only time will tell. I was happy to see they are working to solve the issue.

any swr readings to give?
thanks

 

[Rebel Outlaw]

So basically, anyone considering buying one today, would be better off buying a Sirio Gain-Master?

 

[357]

So basically, anyone considering buying one today, would be better off buying a Sirio Gain-Master?

not really...no

 

[kopcicle]

So basically, anyone considering buying one today, would be better off buying a Sirio Gain-Master?

Actually you would be better off buying an antenna.











;-)

 

[Rebel Outlaw]

Actually you would be better off buying an antenna.











;-)

Can you elaborate? I taught the IMAX and the GAINMASTER were somewhat similar (comparing oranges to oranges)! Are you saying that both are not worth buying?
What would be a good choice for a base antenna?

 

[Big Kahuna]

any swr readings to give?
thanks

I got an extender and tested it between the mid and top sections. I did two tests. One I mounted it on a under eave satellite dish mount so the antenna was just barely above the roof in a less than ideal setup - I did this to test a real world type mounting situation you might run into with many users. With adjusting rings these were best results I could get which were pretty good considering the setup. This was with 50 feet of RG-58 coax/.

26 MHz - 1.412
27 MHz - 1.137
28 MHz - 1.766

I then tested in a open field on a 12' metal pole (so antenna height was 12' at the base). This was with 9' coax.

Best results

26 MHz - 1.678
27 MHz - 1.129
28 MHz - 1.584

Lowest SWR I got after messing with the rings was 1.022 @ 27.2400MHz - which is a great mid CB Band reading.

I also did a test from 26.700 - 27.555 which is a bit narrower with just the CB band and some freeband frequencies that CBer's often use.

26.7000 MHz - 1.235
27.1275 MHz - 1.026
27.5550 MHz - 1.275

Wind was blowing so there were some very slight differences between tests with the antenna bending in the wind.

Extender definitely seems to bring the antenna to it's original length and drop the SWR. I still have my concerns about long term durability but this should solve the SWR issue for most people I'd think. No idea on if/when they'll be rolling them out as I had a very early prototype I believe.