Need help with 1.5m Prime focus dish

[chris2005]

Hi All

I have bought a second hand 1.5m prime focus dish which was dismantled when I got it.

Has anyone got a tutorial on how to set this dish up ?

Many Thanks

Chris

[Giga]

take a look at the constructor's website, if that exist's or google for

AND +"manual" AND +"Prime Focus dish" AND +dish brand where you replace dish brand by its brand

[chris2005]

Hi Giga

I dont see any name on the dish anywhere, I have the mostly setup but i am unsure of setting the latitude . is it just the same as an offset dish do I put the inclonometer on the back and just set it to my latitude.

The three arms are a fixed lenght but maybe I haveto move them to get dead center.

Thanks

Chris

[grizz]

Hello m8y,

Have a look here:-
http://www.geo-orbit.org/sizepgs/tuningp2.html#anchor469886

Hope it helps.

TTfn:)
G

[reboot]

Take a photo and put it on here maybe someone will recognize it. The most popular 1.5 Metre prime focus dish sold in the UK was the IRTE. It is a one piece press soft aluminum reflector with a steel back plate mounted onto its polar mount that sits on a 4.5" post. If its one of these make sure the reflector is not twisted or deformed. They normally are and if it is then its performance will be utter pants.
They are fairly easy to straighten if the reflector isn't dented. I use to place them face down on a level floor to check for any distortion and use a book as a wedge to push the opposite sides to any distortion to press it back into shape.
The other one piece prime focus 1.5 metre which was less common is a Precision these spun aluminum had a steel donut fixed on the back are a rare device and if its distorted then its all over.

[chris2005]

Hi all

Thanks for the replys

The dish is fibre glass with three aluminium arms which are all the same lenght with no adjustment.

I will take a picture of the dish in the morning before I go to work,

Regards

Chris

[chris2005]

Hi all

Thanks for the help,
Everything is working fine now I increased the latitude from what was given for my area and all is working .

Thanks

Chris:respect-055:

[crabber]

Glad it is working, could you post what advantage you get over say an 80cm or 1metre dish.

[ian]

there should be plenty crabber mate.work it out for yourself.
if you take a 60cm dish and compare it to a 1.2m dish then although its only twice the size its actually 3 times the area and its the area that counts not the size,as thats what catches the signal to then focus to the LNB.basic 3.142 maths mate lol.
but also alot depends upon dish quality.a good 1.2m dish can sometimes perform as well as a poor quality 1.5m.Ian

[chris2005]

Hi Crabber

I havent noticed much difference so far still in the setup stages but my channel master 1.2m seems to be just as good .

I just seen it for sale and I thought bigger is better , well thats what the girlfriend always tells me :D

Regards

Chris

[Jimdefruit]

Ian, when I went to school, the area of a disk was based on the ratio of the radius squared and not Pi.

The area difference between a 600 mm dish and a 1200 mm dish is approximately 4.8 times, not 3. However the straight comparison of dish area is very misleading when it comes to satellite signal strength.

An offset dish is very much more efficient than a prime focus dish due to the fact that the LNB assembly does not mask the most efficient central part of the dish. Also, the larger the dish, the more accurately it has to be formed to focus the signal back to the LNB.

I am with crabber in that it is good to find out what actual improvement is obtained with a larger dish. probably because I am nosey. :respect-050:

[crabber]

Thank you all for your input, I wasn't expecting technical answers, as I use only an 80cm dish and have never set up anything much bigger than a metre because of motor restrictions I wondered if I am missing many channels.
I get a reasonable signal from approx 40 degrees east to west and have always been satisfied with this, I am curious to know if there are some weak signal channels or feeds etc I am missing out on. (May be some obscure **** perhaps lol)

[ian]

ah yes mate,you are quite correct i was forgetting the r2
so it would be 60r2x3.142 so yes it is 4.8times larger.
would you believe i have A level maths as well,but its been so long since i used it that i completely forgot the r2 bit and just quickly worked out 60x3.142 in my head to be 3 times the area.doh!!!
Ian.