[TowerTalk] Gotham antennas

[Paul Christensen]

>I remember Gotham quite well.  I also learned the hard way that cheap was
> not necessarily good!  I bought a 4 element 15 meter yagi from them from 
> an
> ad in QST.  When I put it up I could work just as many stations off the
> front as I could off the back and sides and with no difference in signal
> strength!  The SWR was 10 to 1 at the lowest.

The beam antennas actually worked remarkably well although they certainly 
were not "Plug-'n-Play."   The building experience was more akin to a 
magazine construction project with Gotham supplying most of the parts.  The 
gamma match simplified things for Gotham.  There wasn't a single component 
used that was custom manufactured.

The instructions called for making the reflector 5% longer than the DE, and 
the directors 5% smaller than the preceding elements which, were spaced 
evenly on the boom.   Without exception, the most difficult part of assembly 
for the beginner was creating the gamma matching section, finding a suitable 
tap point, and adjusting a series compression trimmer accordingly to yield a 
VSWR of 1:1.  Other than supplying a hose clamp, Gotham left the design of 
the gamma section up to the owner.  It was a shame, really -- so many 
beginners gave up like you did.   At the very least, Gotham could have 
supplied thin tubing and an input termination point.  No terminals.  No 
SO-239 connector.  Only a set of instructions that told you to connect your 
coaxial able to the gamma section that YOU designed.

Switching to the TA-33 from the Gotham was one of the happiest days of my 
youth.

Paul, W9AC