At 11:05 AM 11/12/99 EST, N4CW wrote:
>My old TA-36 (vintage unknown, but precedes the "Classic" series) has a
>unique feed. The trapped driven element is insulated and fed at the center
>a balanced fashion. However, the coax from the station goes to a tee at the
>antenna, and each side of the tee connects to a 47" length of RG-8. At the
>far end of the coax, you strip back the outer jacket for 3 5/8", undo the
>braid from both pieces, twisting them together and solder on a solder lug.
>The center conductors are stripped back 1/2", twisted together and a solder
>lug is soldered to those. Each solder lug is connected to the feed points of
>the driven element.
>I have no idea how the transformation from a balanced antenna to an
>unbalanced feed line takes place with this configuration. But it does work,
>albeit nowhere as good as other antennas I've had.
Sounds like a lossy T-match, using the capacitance of the RG-8. I don't
see how there can be a transformation to unbalanced taking place in a
symmetrical feed system, so if it were me I'd put a bead balun at the
We had a CL-36 at the State Department ham club that was fed by a length of
coax lying inside one side of the driven element, not electrically
connected to anything. Dunno if that was standard. It, too, worked OK -
73, Pete Smith N4ZR
Sometimes a tower is just a tower
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