IMAX 2000 high swr only over 1KW in ssb HELP!!

[thiokol]

might be the wrong place please direct if wrong.

hello all and thanks in advance
i have a imax 2000 when im in ssb and i push up over 1kw
i jump from 1.3/1.5 to 3-4 plus
listed below is list of components
any thoughts ???


LPA 100 meter
2995dx 1-4dk\30\40 pep
Tstar dx1600x
homebuilt 2x8
LDF 5 50ohm coax
jumpers are all 213
all connectors are silver amphenol
and or Andrews

[222FL]

Antenna won't handle the power!! Bottom line. Get some N-male connectors or even Din Male connectors and upgrade the antenna itself. This is just what it sounds like to me. These antennas are over rated as far as power goes IMO, and I have seen a couple burn out with less power. With the power you're running why not look into something like a shockwave antenna?? Much better antenna and will handle the power you are using no problemo!! Again, JMHO. Good day.

[source]

i agree with that imax 2000 cannot handle tha amount of power you will need something without coil would be better. omin directional or beam

[222DBFL]

Like I said in my first post. You want to run a lot of power, things have to be upgraded. Connectors, coax, and most importantly the antenna. A US made Shockwave antenna, Mr. Coily, or an I10K will do the job. Same goes with the other things I listed. Coax wise, LMR400 or even LDF4-50A would be the way to go. Use N type or Din type connectors as well. The LDF4-50A has little loss and this equates to more ERP at the antenna. Also 1/2" superflex coax would work well too. Again, these are JMHO's. Have a good day and a Happy New Year!!!

[radioreddz]

I have been running 1500 to 2000 watts thru a Imax for years with no problem is your amp a 2x8 tube or 2x8 transistor.

[222DBFL]

Just because you have a decent VSWR, it doesn't tell the whole story. There are other factors to consider such as impedance and reactance. Just some food for thought. I've seen antennas show a good VSWR but the impedance was way off and the reactance as well. Just some food for thought. Also don't believe everything you read about power ratings. JMO.

[source]

remember the imax can handle up to 5000 watts any thing over that you goose cooked.true words on that.

[222DBFL]

I wouldn't run 5k watts through an IMAX 2000 ever! But that's just me. Don't believe what the manufacturer posts about the power handling of most any antenna. I would keep the levels below 1kw. As I said before you might have a good VSWR, like a 1.2:1, but the impedance and reactance can be way off and that is no good!! JMHO's. An antenna analyzer will tell you the whole story. What R and X is and VSWR as well.

[Jay Mojave]

Hello All: Yeah I think the I-Max 2000 will NOT handle the power your sending it. I have heard over the years that some of theses antennas do handle a few KW and some do not. See:

http://www.extremecb.com/2000wfuse.htm

Changing of the connectors will not help, with the I-Max 2000 matching coil has loss to it, it gets hot with the high power and changing its matching value. So a higher VSWR is seen, until it cools off. And some times it doesn't come back to a lower VSWR, after cooling off.

Jay in the Great Mojave Desert

[BOOTY MONSTER]

why and how are you checking the vswr in ssb mode ? going from AM to SSB won't change vswr ... vswr is effected by tuning frequency and reflection (nearby objects) effecting the antenna .