In a message to Wayne Sarosi  Rob Dennis wrote:
 > WS> Any ideas for a new series on antennas?
 RD> How about a TV antenna conversion to 2m or 70cm ?
 RD> Not one of the `average' type tV
 RD> antennas most people have but one of those
 RD> large `fringe range' antenna monsters.
 RD> Largest one I have seen in RS catalogue is over 6 feet long and
 RD> would be a nice base to start from for a 70cm beam.
 RD> Or maybe use it for a VHF/UHF LPDA base of `parts' to start with?
 RD> Slice the boom down the middle
 RD> length-wise and then work on the elements and
 RD> spacing a bit to cover 144,220,440,900MHz .
There is a lot of cutting and modifications to get a TV antenna
to work on the ham bands since the antenna is made for TV channels.
It's actually easier and cheaper to make your own LPA to cover 50-1000
MHz. There are spacing problems, element lengths, matching. And if you take a 
close look at a TV antenna the elements are folded not spun or drawn.
With all the work required and you would have to have a very good 
understanding of TV antennas.
 RD> What about the antennas that look like a
 RD> parabolic dish for TV channels 14 and
 RD> upward ? I see this type a lot in the
 RD> upstate New York area on several houses.
 RD> Wonder if it can be used as a platform for a  1.2GHz or 10GHz project ?
Now this one is possible especially on 10GHz. 
Just change the feed and go for it.
-WS
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