Cambio wrote:

My recollection of a turnstile antenna is two folded dipoles at 90 degrees
to each other.

Yes. Although not exactly clear, that is what the Winguard is, although I would
have expected a little better radiation pattern. Note the data sheet gives "2
active elements" and the drawing sort of shows the othagonality. The 90 deg of
twin lead is visible too.

See URL:
http://www.qsl.net/wb8erj/turnstile_antenna.htm

A search of radio shack catalog does not show one nor is it in the manual
lookup section

There is a part number (150-1639):

http://support.radioshack.com/support_video/32581.htm
(linked from http://support.radioshack.com/support_video/15785.htm)

However there is a Lindsay turnstile at URL:
http://www.lindsayelec.com/fm88-108.html

Probably very nice quality, but look at the price! Most consumers won't dream
of spending that much.

Antennacraft makes one too.

http://www.antennacraft-tdp.com/pdfs/FMSS.pdf

http://www.starkelectronic.com/fm.htm

I'd say $19.20 is a little more like it for the consumer. I'd spray a few coats
of Krylon Crystal Clear on it before I put it up.