Is the "Slim Jim" a good antenna?

[joseph2020]

Does anyone use the "slim jim" antenna and if so what do you think? I am looking for something very portable/flexible, but some gain/low swr on 2 meter. All opinions are welcome. Thanks in advance.

[LtDoc]

If the 'slim-jim' fit's your needs it should do as well as any other antenna of the same type. 'Gain'? Not really, it's basically a 1/2 wave antenna with an impedance matching system. It should provide more 'gain' than a typical 1/4 wave antenna, but nothing really exceptional. It's primary benefit is that it's portable, can be 'wadded' up into a small space, and can usually be hung just about anywhere. One draw back to them is that they won't usually stand up all by themselves, too flexible. If that satisfies your requirements for an antenna, have at it!
- 'Doc

[groftcc]

I have two dual band Slim Jim's and a Diamond X-50 in my attic. The Slim Jim's noticeably outperform the Diamond on VHF (144). On UHF(440) the X-50 has the advantage.


Craig

[UberGeek]

Originally Posted by joseph2020

Does anyone use the "slim jim" antenna and if so what do you think? I am looking for something very portable/flexible, but some gain/low swr on 2 meter. All opinions are welcome. Thanks in advance.

Not much gain so to speak. It's efficient for 2 meters, is portable, and flexible. Not portable enough to walk around with a handi-talky and use it, but portable enough to carry it around.

[WA1ATA]

There is a lot of info floating around on J-poles. The J-pole is a 1/2 wave dipole, end fed with a transmission line matching network about 1/4 wavelength long. The slim jim is the same design, except the 1/2 wave dipole is replaced by a folded dipole.

I have built numerous J-poles and slim jims out of 300 ohm twinlead for receive only use, usually centered on either 124MHz for VHF airband or 157MHz for marine VHF and railroad. As others have noted above, the performance seems to be a bit better than a simple dipole.

It's a simple, cheap, easy-to-build design. Just do it. Don't forget to come back and tell us how it worked for you.

[majoco]

All the information you could possibly need, and then some more!

MØUKD - Slim Jim Antenna Calculator Dimensions

[joseph2020]

Thanks for all your replies. It sounds like the antenna for me, although I probably will buy it already made, as I have zero experience building antennas, and with RF connectors...it is only $23 built and tuned by the designer, so I'm sure it is much better built than I ever could with my present knowledge, and I doubt I could get all the parts for that much anyhow.

majoco: a special thanks for that link, very educational.