Installing a 1.2m channel master / polar mount help required please.

jenseneverest

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Hi all,
After picking up an ebay bargain a while ago i rebuilt the polar mount and mounted the dish at the start of the summer, since then other things have had to take priority over the hobby.... I hope to get a chance this week to finally finish it off and get it working. I have bought a new vbox, ram, cables etc that have just gathered dust for months now......

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At this point i am pretty dam confused as to how to set it up, the scale on the threaded bolt has long since rusted off the polar mount.
I moved everything about when i had it in bits so now have nothing to work off as a starting point.
The declination angle at the top of the mount is also very confusing as that scale is actually marked as "latitude"
What confuses me further is the dish is also offset.
I have an inclinometer and a basic sat finder / compass
My latitude is 51.5403 ( Essex area )

Some help as to where to measure.... and what my angles should be...... would be really great !!

For a start this scale is just doing my head in

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Dose the dish offset have a bearing on this declination angle ? The only detail i can find for the CM 1.2 offset is 22.6 degrees is this correct ?

Assuming i can somehow figure out how to correlate the number of theads to the scale (no missing on mine) an the lat adjuster is it measured with the green or orange line in the pic below ??

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Im obviously lost lol, any help or pointers appreciated

TIA jensen
 

Mickha

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Hi Jenseneverest, welcome to the forum.
First off, looking at your pictures, the dish seems rather tightly sited, so a motor would only damage your dish, as it needs to move East/West, Left Right, to track the satellite arc.
Do you have any idea where the dish is pointing, in the pictures?

I would advise that you start with dishpointer.com, to give you a general idea.
Type in your postcode, in the location box, select 0.8W, from the drop down satellites box, then zoom in on the map, keeping the green icon in the frame, then locate your house, and move the green icon to where you have your dish sited.
The green line will show you which direction the dish needs to be pointing at.
 

Channel Hopper

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Elevation bolt numbers are from memory taken from the uppermost nut.

You will need to look at a chart that converts your location coordinates to the latitude, the number that comes out is already calculated for you on the declination setting, no need to take the dish face into account.
 

a33

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Welcome to the forum, Jenseneverest! :-welcome1

Modified motor angles (0-180 degree fit) for your latitude would be:
rotation axis elevation angle = 37.8 (against the vertical)
declination offset angle = 6.8
Total elevation angle due south 37.8 - 6.8 = 31.0
Dish face angle due south = 31.0 - 22.6 = 8.4 degrees; that is, if the LNB feedhorn is placed at exactly the focal point, in proper offset angle.

To check the latter, see the link (RimaNTSS picture of Channel Master dishes) in this post: Raven 1.8m Install Progress - SatsUK

Inclinometer is usually more accurate than the scales on the mount. :)

I hope you get it all fixed, now.

Greetz,
A33
 
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jenseneverest

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Thank you all for your replies, light is fading today i will hopefully have a go at this in the morning :Y

To clear up a few questions, yes the fence is not ideal, in fact no where in my garden would have been.... and the front of the house over looks a public footpath and the local park, i already have a 80cm motor and 2x 60cm fixed dishes dishes out there to the delight of my neighbours.....
In the picture the dish is as far over to the west as it can go, i would imagine around about 7/8west
At a guess I should have clear line of sight from about 7/8 west to 42 east. Will update once we get it working!!
 
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