Playing with old technology - BSB Squarial and mini dish

[nvingo]

Originally Posted by breezybadger

I did manage to receive some sort of image from Hispa on my squarial
...
but thinking about it now I probably didn't compensate for the frequency shift...

And the skew.
As a motorised dish moves between the extremes, it also rotates about its axis, keeping the polarisation lined up with the satellite transponders.
With a fixed dish, the skew is set by the LNB/mount/arm assembly.
Since Hispa was quite a distance from due south, its skew would need noticeable adjustment.
Skew is irrelevant for circular polarisations.

[breezybadger]

Originally Posted by nvingo

And the skew.
As a motorised dish moves between the extremes, it also rotates about its axis, keeping the polarisation lined up with the satellite transponders.
With a fixed dish, the skew is set by the LNB/mount/arm assembly.
Since Hispa was quite a distance from due south, its skew would need noticeable adjustment.
Skew is irrelevant for circular polarisations.

I did actually set the skew as best I could when I was trying it out, but as I say, I didn't compensate for frequency shift, so couldn't get a picture that I could try to improve on...

It was a while back though (about 2 years ago I think), so the specifics of what I did are a bit faded...

[pudwink]

I spent hours in my garden with my squarial after i brought it from a show got a fuzzy picture but that was it.

[Kay B]

@ breezybadger

> I tried to build an LNB to fit onto the back of my Squarial, but as I had no
> clue what I was doing, it didn't really work, plus the feeds were the
> wrong shape, the squarial had a rectangular on and the LNB I was using
> had a round one, round peg square hols and all that!!!

The LNB has to be electrically connected to the squarial.



@ nvingo

> The Squarial contains an array of LNBs on the PCB. Polarisation is circular
> determined by the print on the plastic sheets in front of the PCB. Flipping
> the top sheet (so the print is mirrored) changes the circular polarisation.
> Linear polarisation can be received, but only one thereof as there's no
> facility to switch it.

So, the polarisation of the squarial without the plastic sheet is linear, right?