Losmandy GM8 Not Slewing

[Ramsay11 (Stephen)]

I just picked up a new GM8 with the Digital Drives. I have a spare 12V ATV battery while not at its optimum, is delivering enough voltage (12.4V) and current to power the mount. Once powered up both stepper motors can be heard (tracking) but attempts to slew the mount yield no results. All power and RJ45 cables are properly connected and the RA motor is barely making any sound. I have adjusted adjusted both clutches and suspect one of the following

Either the RA and DEC worm drives are seated too tightly into their respective gears or,

I have a faulty Digital Controller (hope not) or the battery isn't supplying enough juice

I have logged a message from Losmandy hoping to hear back from them.

I would appreciate it anyone have any suggestions and shed some light on my experience and recommend a proper power supply battery (AH rating)?

[rmcconachy]

The Digital Drive Losmandy mounts don't really `slew' at all. Losmandy suggest that you manually move the mount to point near the object of interest and use the motors to make small corrections and track. The maximum drive rate is only 16x sidereal rate (might be 32x for the GM 8, I cannot remember). At this slow rate (16x sidereal means 90 minutes for one complete revolution) it is easy to not notice the movement if you are looking at the mount rather than through a scope sitting on it, so are you sure that it isn't working? If you put a scope on the mount and look at an object while using the hand controller do things move around as they should and do they move more quickly when you increase the rate on the main controller? Sorry if this seems insulting (it isn't meant to be!) but I've seen others bitten by the slow `slewing' speed before. Jeff makes another very good suggestion below.

The Digital Drive system has a maximum current draw of about 0.5A so any decent battery should last for a while (I use a 24Ah unit which is huge overkill).

[Jeff]

Could also be a simple problem with the hand controller or cable.
Can easily check continuity with a multi-meter if you have one handy.

[gb_astro]

If you want slewing you will need the servo motors.

gb.