Calculations for rotor and dish?

meeko

Newbie
Hi all

Hopefully a quick question. I'm about to restart mounting my dish
(Actually I'm getting a 90cm round to put on my Technomate TM2300 Mk2)

I just have some doubts about calculating angles. Elevation/Latitude on the motor is easy enough: 53.5° for Manchester. I'm just unsure of the declination angle/dish angle. I'm getting various conflicting answers, 7.6°, 22.4° and 39° depending what I read!

Can anyone indicate what it might be, and the correct way to work it out?

Thanks!


__ edit
I am becoming more confident of:
Site latitude is 53.5 (from OS map! Amongst other things)
So I set rotor latitude scale to 53.5, NOT elevation scale 37°
Declination is 7.6 (from rotor manual)
Therefore rotor manual suggests dish angle 22.4° approx?

Does that sound about right?
 
Last edited:
Sounds ok for rough setting up.

You could use dishpointer on your phone for the above calculations.

Ensure your mounting pole the motor fixes to is 100% plum in all directions.
Ensure the dish on the motor is mounted straight as a centre line from motor stub.
Set your motors elevation to 53.5
Set your dishes declination rough.
Move the whole dish motor setup around the mounting pole to as true south as you can.
Send your motor to 0 leave usuals off on the TM for now but select a channel on 0.8 west.
Move the whole rig till you find signal or the correct channel clears.
Peak signal moving the dish motor left to right around its mounting pole and tighten up making sure signal does not drop.
Then peak the signal for dish declination moving up and down and tighten up.
Apply usuals settings on the TM and move sat to see if the dish is tracking the arc.
 
Last edited:
Sounds ok for rough setting up.

You could use dishpointer on your phone for the above calculations.

Ensure your mounting pole the motor fixes to is 100% plums in all directions.
Ensure the dish on the motor is mounted straight as a center line from motor stub.
Set your motors elevation to 53.5
Set your dishes declination rough.
Move the whole dish motor setup around the mounting pole to as true south as you can.
Send your motor to 0 leave usuals off on the TM for now but select a channel on 0.8 west.
Move the whole rig till you find signal or the correct channel clears.
Peak signal moving the dish motor left to right around its mounting pole and tighten up making sure signal does not drop.
Then peak the signal for dish declination moving up and down and tighten up.
Apply usuals settings on the TM and move sat to see if the dish is tracking the arc.
Thank you so much for the advice!

I understood the principles but was unsure of the actual figures. I'll give it a go and report back progress!
 
The only figure i care about is the motor setting the castings markings on a dish are always rough and a get you in the ballpark guide should be applied with those.
 
If your using usuals sending it to 0.8w is fine as usuals will of calculated the true south offset.
 
But if your using usuals with your cordinates usuals calculates for true south.
 
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