Just Sharing This 2.2mtr Elite / Precision resurection... Part 2.

[John]

John,

What type of mounting arrangement did you use for the Precision 2.2m dish? From the couple of pictures showing a partial view of the back it looks like you have fabricated some type of mounting and not adapted the CM 1.8m mount to fit?

Rgds

The triangle mounting bracket is off a Precision, can't remember too much about it's origin. It was used on my old 2.2 that got trashed using a "Jumbo" H-H motor, hence the now unused mounting tabs that can be seen. It's now got a few more tabs stuck onto it to suit the home brew polar mount and it's actuators but i never bothered to take the old tabs off D.
Picture was took quickly looking through glass window, iphone on zoom etc so not a very spectacular pic but you get the idea.
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[moonbase]

John,

Thanks for the quick reply, I recognise the triangular mounting bracket, its from a Precision polar mount. I have attached a two pics of the mount below.

A feature of this particular mount as supplied by Precision was that it orientated the dish so that there was a vertical feed support arm in the lower half of the dish when the dish was at its zenith. The other design of the Precision polar mount did the opposite, it orientated the dish with the vertical feed support arm in the upper half of the dish when at its zenith.

I am not sure of the reason for the different designs of polar mount from Precision. One thought I had was that the version with the vertical feed support arm in the upper half of the dish might have been for heavy feed arrangements with the weight of the feed distributed downwards into two feed support arms, however, its just a guess?


Rgds

 

[John]

... This is an interesting read, taken from public domain of Elite Antennas Ltd.

https://www.elite-antennas.com/uploads/A Question of Accuracy.ppt

 

[s-band]

MB, I may have missed it but are you going to add inclined tracking?

... This is an interesting read, taken from public domain of Elite Antennas Ltd.
https://www.elite-antennas.com/uploads/A Question of Accuracy.ppt

Thanks, John. That really brings home the potential for additional losses. I probably won't use the Fortec for 32GHz deep space work.

 

[John]

MB, I may have missed it but are you going to add inclined tracking?



Thanks, John. That really brings home the potential for additional losses. I probably won't use the Fortec for 32GHz deep space work.

Oh ye of little faith

 

[moonbase]

... This is an interesting read, taken from public domain of Elite Antennas Ltd.

https://www.elite-antennas.com/uploads/A Question of Accuracy.ppt

John,

Thank you for the link, interesting read.

There is also a Ka Band paper by the same author somewhere on the Elite Antennas web site, have you read it, its another interesting read?


Rgds

 

[John]

Yep, seen the other report, this latest one is fairly new to the site in the last month or so. When i picked my 2.2 up they had a 4.5m Ka reflector i think it was, in bird bath position undergoing the random reference points laser accuracy surface calibration adjustments using those turnbuckles that the paper talks about. Really good to see and touch such a thing being optimised.

 

[moonbase]

Yep, seen the other report, this latest one is fairly new to the site in the last month or so. When i picked my 2.2 up they had a 4.5m Ka reflector i think it was, in bird bath position undergoing the random reference points laser accuracy surface calibration adjustments using those turnbuckles that the paper talks about. Really good to see and touch such a thing being optimised.

John,

It would be very interesting to see in practice what the signal levels were like in C band or Ku band on a like for like comparison. For example, a non Ka optimised antenna vs a Ka optimised antenna of the same size but operational on Ku or C. If I were to guess, I would say the signal level difference would be marginal but the increased cost of the Ka optimised antenna would be huge?


Rgds

 

[John]

John,

It would be very interesting to see in practice what the signal levels were like in C band or Ku band on a like for like comparison. For example, a non Ka optimised antenna vs a Ka optimised antenna of the same size but operational on Ku or C. If I were to guess, I would say the signal level difference would be marginal but the increased cost of the Ka optimised antenna would be huge?


Rgds

.. Yes agreed, i think it said in that latest paper that it was £1600 / day ex vat for laser set-up with turnbuckles etc. If it ran into a few days then yeah-- mega bucks