Double axis motor

[Froggz]

Hi,

I am just starting to use my motor on my eq5 and something is driving me to distraction: I was watching Jupiter when I realised it was drifting to the left of my eye piece. I stopped the motor and Jupiter was then drifting towards the top of my ep. I am obviously doing something wrong but what is it? I think my tripod is set to the North Star and is level. The 'bolts' were tight on the motor and I only had water for dinner. Any ideas?

Cheers

Ben

[Cornelius Varley]

Things to check :

1. polar alignment

2. the handset switch is set to "N"

3. the cables from the handset are going to the correct motor.

[Froggz]

Hi, thank you. I guess I will have to check the polar alignment and the cables .. would either of these points explain the drifting to the left with the motor on and the drifting to the top with motor off though?

[JamesF]

"Left" and "top" are quite arbitrary directions depending on the type of scope and its orientation. Giving the drift in terms of compass directions might give a clearer idea of what's happening.

The three things Peter suggests are the first things to check, without a doubt. If the motors aren't connected to the correct cable then the handset will drive the DEC axis instead of RA when no buttons are pressed and that will obviously cause drift in both DEC (because the axis is moving) and RA (because it isn't moving to counteract the Earth's spin). If that's right, but the hemisphere selection button is set to "S" rather than "N" then the target will appear to drift to the west very quickly because the RA axis will be turning "with" the Earth rather than "against" it. Speed selection isn't important because it only affects what happens when you press the pushbuttons.

If polar alignment is out then you'll always get a certain amount of drift. If you're not perfect but close it won't be very much and if you're a fair way out it will be far more obvious.

James

[Froggz]

Hi James, thank you very much for these explainations. I was watching Jupiter in the west and it was drifting south (apparently, in my ep) with the motor. I am not sure how to describe the apparent drifting of the

object towards the top... I guess it was sort of 11 o'clock if I look at a vertical watch . I have an explorer 200p on eq5 mount.

I will try again and check all these points a bit more thoroughly.. as soon as the sky clears that is. .. I was also wondering about the 3 different speed on the control so I could more or less ignore that for now.

Ben