"sangeo" wrote in message
...
I came across a good 2 meter 12 element beam. The boom is aprox 19 ft
long. It has 4 driven elements in a "log" or lattice configuration. I
need info to make the coax connection. Does anyone have an Idea as to
Mfg? The driven elements are spaced about 7 inches apart. It is in
good shape except for the missing connection points.
Thanks, 73's
George

The manufacturer of your antenna may be KLM (SK). I sniffed this out:

http://lists.contesting.com/_towerta.../msg00259.html

Some KLM products rolled into M2 Antenna Systems
http://www.m2inc.com/index2.html It doesn't look like M2 offers any antennas
fed through sleeve baluns or sells any sleeve baluns separately.

Also, I have a two 440 beams with the closely spaced "lattice"
configuration of multiple driven elements -- as you described. They are fed
through quarter sleeve baluns. 16/17 cm long, cut on an angle at the open
end, if it matters. One of the baluns still has the mfr sticker on it.
Would you believe "KLM"? I could post a picture.

From this, I suspect the feed point impedance is close to 50 ohms. I
mention impedance only in passing, as I encountered some references to
impedance transformation through half-wave sleeve baluns. I haven't
investigated that aspect.

I googled for "sleeve balun"and at first glance, this looks OK.

http://www.vhfman.freeuk.com/radio/sleeve.html

Making your own sleeve balun looks easy enough. However, I saw more
than the "normal" share of weird s**t on the 'net about making sleeve
baluns. Sleeve baluns are good -- don't misunderstand. Just be careful.
Read a lot.

Multiple toroids slid onto the coax also form a balun. IIRC, advice was
posted here recently regarding fifty toroids for HF. Could be that toroids
also work well for VHF. Others will know. Good luck and report back.