On 07/06/2021 13:58, T i m wrote:
On Mon, 7 Jun 2021 12:50:38 +0100, williamwright
wrote:

On 07/06/2021 09:11, T i m wrote:
Yeah, I think they are also called polar mounts, slightly different to
an astronomical equatorial mount.

The geometry is a bit weird. Really big dishes take quite a bit of
setting up.The thing sweeps across the arc by virtue of a fairly simple
pivoting arrangement, but then there has to be 'declination offset' to
compensate for the fact that the dish is not at the centre of the earth.
It's done by setting the tracking arc a bit high then adjusting a offset
to drop the dish down a fixed amount on the swivelling mount. Then you
start to think about polarisation offset!

Back in the day I installed about 10 'Maspro' systems for friends and
family and a couple were 'motorised' so I had to deal with all that as
well. I found it all very interesting and it was all quite new at the
time (in domestic circles).

I obtained them 'trade' though the Co I worked for at the time and
installed them for nowt for the fun / experience of it.

My dish was just on an old tripod stand at the bottom of the garden
and it was only an issue if I walked in front of it ... but if / when
that happened, *I* wasn't watching satellite TV. ;-)

(From memory) The dishes were solid steel (not mesh), 90cm, offset LNB
jobbies, with a separate polariser and with an elevation of around 27
Degrees around here meant that the front edges of the dish were nearly
vertical (or close enough to get *some* signal) and the Astras could
be seen between the chimneys. ;-)

Having it at ground level made it much easier for playing with
different LNB's etc.

Cheers, T i m


They were happy fun-filled days.

Bill