Windmill wrote:
Are steering mechanisms sufficiently stable, and sufficiently precise,
to allow use of the same dish with both TV and broadband?
(Obviously two LNBs slightly offset from each other might be required,
depending on frequency etc.)

Won't you have an issue that the signals come from two different satellites,
at two different angles? Both geostationary, but one at XX degrees W and
another at YY degrees E, or whatever. Or are they on the same satellite?

Do steering mechanisms use stepping motors, so that there is a minimum
possible angular change, or are some/all capable of any desired degree
of movement?

If there's servo control then high resolution should be possible
(nanodegrees or something), though whether you can buy such a thing cheap
enough and designed for satellite positioning I don't know.

Theo