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Ukastronomer
05-05-2019, 08:23 PM
As I am no way an engineer or electrical person I hope you may help.

The AZ Skywatcher mount in the image has knobs that come off, I am considering placing something similar to this on each one

Image 2

But the skywatcher is not powerful enough, I don't want to pay hundreds, any ideas, many thanks

RyanJones
05-05-2019, 09:06 PM
Hi Jeremy.

It depends on how fast you want it to move. If the answer is fast and you want to run direct drive then the motor has to be quite large and powerful. If you're happy to have it move slower then a high RPM but weaker motor with gearing will do the job. I don't know about in the UK but there are electronics shops over here that sell the motors and then variable gearboxes that you can use with them.

Ukastronomer
05-05-2019, 10:20 PM
If I am simply using it to move with the Moon then obviously not fast

Thanks

RyanJones
05-05-2019, 10:34 PM
My assumption is that those cables are already heavily geared to the mount heed ? Several rotations of the knobs doesn't move the mount significantly ? Are you planning on having this setup constantly following the moon or purely as an electronic hand ?

Ukastronomer
05-05-2019, 11:37 PM
No I thought that instead of moving by hand it would be easier to have two of these motors one on the updown the other on the leftright

raymo
06-05-2019, 12:10 AM
It could be done easily enough, but you would need a pretty high speed direct drive, or you would soon get impatient when slewing across a large part of the sky, and that would leave you finding very small movements difficult, so you
would ideally have a variable speed setup like the SW motor kit in your pic.
Would be cheaper to get a tripod already so equipped.
raymo

Ukastronomer
06-05-2019, 01:45 AM
All I want to do is control it with a remote rather than manually with a knob, slewing and speed are not what the SkyTee is for

It is obvious that you have to keep taking your eye from the eyepiece to find the knobs where as you can hold remotes in the hand still looking !

Wavytone
06-05-2019, 07:51 AM
Aaah ... so you want the impossible dream. Unfortunately Jeremy there really is a reason why people pay quite a lot of money for what you ask, it is not trivial.

- a small altaz mount,
- that tracks,
- doesn’t cost a motza.

You can have any two, but not all three.

There are solutions but they all entail buying a new mount - not adapting yours which was never built with motorisation in mind.

A not insignificant part of this is that it entails a small computer of some kind to work out what speed/direction the motors should turn, for which it requires knowledge of the location, date, time and where the scope is pointing. And for that to work it needs encoders of some sort and also a calibration routine.

In other words the functionality of the SynScan handsets, or the equivalent.

Possible ways:

- buy an iOptron Cube, this is the simplest all-in-one altaz solution;

- buy a Skywatcher AZ-GTi, AZEQ5 or the much bigger AZEQ6;

- find and buy a secondhand T-Rex (has worm drives) and find a “train & track” gadget (was used with dobsonians) and somehow connect the two.

- buy a Losmandy AZ8, which has the worms and fit motors from the GM8 (which is similar but equatorial) then figure out how to build and program your own handset, by which time you will have earned a degree in electronics.

- buy a Rainbow Astro harmonic drive mount. That is around $US 10k.

bojan
06-05-2019, 08:09 AM
You can have all three.. but as you yourself are not "electrical" person, you have to find a friend who is (or to persuade the exisying friend to join a "dark" side).

Then have a look at ONStap system (http://www.stellarjourney.com/index.php?r=site/equipment_onstep). It will cost you $100 max. Plus friend

Ukastronomer
06-05-2019, 05:26 PM
I think I have explained it wrong (or people have got it wrong)

All Iis where to get a motor and control box from that can turn a small load, adding a bracket to the mount is easy

Eccoders, handsets have ZERO to do with it, no more than it has with a focusser

raymo
06-05-2019, 09:31 PM
At its simplest you need a control box which will turn either motor in either direction as required, and unless you fit clutches so you can make large movements manually, it will also need to have a large speed range, unless you are prepared to wait half an hour for your motors to
take your scope to a new target many degrees from your current one.
This setup is not trivial.
raymo

taminga16
06-05-2019, 09:40 PM
Wander about your neighbourhood in search of a 'Ham Radio' operator, he or she will ham the skills that you need. 'Putting the unity back into Community'.

LewisM
06-05-2019, 10:44 PM
This is the result for how I interpreted what you are asking: https://myastroshop.com.au/products/details-item.asp?id=MAS-022E...but its about £106

raymo
06-05-2019, 11:20 PM
That's a good suggestion Lewis. On an EQ3 that kit gives 8x sidereal, which is pretty slow, but it as you know has clutches so he can make large adjustments manually. I wonder what the gearing on Jeremy's mount would give; if it is significantly higher than an EQ3 it might
stall the motor, although come to think of it, he could use the 2 or 4x speeds and forget the 8x.

raymo

RyanJones
06-05-2019, 11:23 PM
I get what you're asking for. As I first put it, an electrical hand. Press a button rather than manually turning the cable.

Having said that, I agree that the easiest way would be what Lewis has suggested.

Ukastronomer
06-05-2019, 11:25 PM
YES something like that, you get it thanks

Ukastronomer
07-05-2019, 02:37 AM
100% Thanks again Lewis

The one i showed, again here would be 100% perfect it just isn't powerful to do the job

I would use TWO, one for up down another for left right

In case anyone wonders, not everyone has the movement in their hands to turn knobs but they can PRESS buttons

THANKS for the info Lewis, I have made a saved search on ebay for a used one Thanks again all

Ukastronomer
07-05-2019, 05:50 AM
I have ordered the following two items (I have a batter box somewhere !!!!)

I know I will be told they are the wrong thing PLEASE if you know, but they are very cheap on Amazon, I hope to try to make one of the two controllers, if it works I will do another