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RE: Need Tripod Mount Advice



Hi Bob and the group,

While getting ready to move, I'm temporarily using two cheap tripods - the
cheapest ones I could find with a pan head mount (about US$19). I use one
for the BBQ dish (Andrews 24T240) on the downlink and the other for the
10x10 element crossed yagi for the 70 cm uplink.

The Andrews is mounted with the dipole feed horizontal, which means the
reflector widest dimension is in the vertical axis. Besides being the easier
to handle this way, it puts the wide beamwidth parallel with the orbit and I
don't have to re-aim it as frequently since the azimuth seems to change much
more frequently than elevation. Usually have to adjust it about every 1/2
hour to 45 minutes depending on the MA.

The Andrews comes with a L bracket which is adjustable in axis and I just
tapped the L bracket for the camera tripod thread. I added an extention to
the bracket and mounted the Drake converter and DEM 13ULNA preamp there
which adds a little counter balance. Its fine for portable / temporary work
and hasn't fallen over yet.

For the uplink 70 cm crossed yagi; the boom extends about six inches beyond
the reflector element, so I drilled and tapped that part of the boom. This
really needs a counter balance, and I tied a large lead fishing weight. Its
still flimsy, but again, this is just for portable operation. Since the
camera tripod I used is plastic or composite, probably could have tapped
near the center of the boom and not affect the uplink much. That
configuration might be easier to handle in your apartment.

I had tried a helix on the downlink, which was very easy to mount using an L
bracket tapped for the camera tripod and downconverter / pre-amp, but I'm
much happier with the Andrews dish.  Also, I had tried mounting both the
helix and 70 cm crossed yagi on one tripod using a cross boom, but it was
very unstable. The two tripods configuation really works out good.

I'm using a FT-847, so could probably cut the 10x10 crossed yagi in half to
make a shorter uplink antenna and still have a useable uplink on SSB with
just 5x5 elements. This would really work out well on the tripod.

Hope this gives you some ideas. I'm quite happy with the arrangement. Just
takes a few minutes to snake the coax out to the patio, bring the antennas
out of the garage, and hook everything up. Sorry I haven't any photos yet.

73, Ken, W7KKE

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