Synscan noise

[Ludd]

I recently bought a synscan goto kit for my Vixen GP mount and have used it a few times. The accuracy of the goto function is great, and it tracks nicely and quietly, but I'm concerned that the noise at full slew speed is at a level that's going to be a serious annoyance to neighbours. It doesn't sound as though anything is wrong with the gears, it's just that the sound of the mount accelerating up to 800x speed is loud and intrusive. That might be fine in the winter when observing not too late and when people will have their windows shut, but in summertime (if we get there!) it could be a real problem.

Unfortunately it seems there is no recognised way of telling the motors not to bother going at full pelt when slewing - you tell it to find something, and it races off in a tremendous whirring and whining that echoes round the neighbourhood. You can set the slew rate for manual slews, and to be frank the speed setting of 6 is plenty fast enough for my purposes without being noisy, but the motors crank right up to 9.

I could slew manually to the objects I'm after and use goto only for the final approach, but that slightly defeats the purpose of having this kit (it might as well be push-to) and in any event I'm convinced that this would result in the mount deciding to take the long way round and slew 359 degrees round to the object I'm after. In contrast, I've got an elderly GPDX with DK3 drives (from the land of Bern) that runs silently - even at x32 slew speed you have to be right next to the mount to hear the gentle purring.

Does anyone know a way of limiting the goto slew speed on these kits? Or should I think about abandoning goto and selling this kit?

[Merlin66]

Do you have the Synscan controller??

It's a while since I checked (I've gone over to the EQmod...) but there should be a way of limiting the slew speed from the menu?

[Ludd]

Yes, it's the synscan handset that came with the kit, but I've not yet found a way to limit the goto slew speed.

[OzDave]

Yes, it's the synscan handset that came with the kit, but I've not yet found a way to limit the goto slew speed.

I'm not sure you can limit the slew speed from the handset. However, I believe that EQMod has a feature that can do this. I remember reading a thread where it was discussed. That might help if EQMod is an option for you.

Sent from my iPhone using Tapatalk

[Ludd]

That was my fear - I don't think I'll be venturing into the world of EQMOD in ther foreseeable future and want to be a bit less tied to a PC when observing.

[chrisshillito]

Sorry but I don't believe that option exists yet. The synscan handcontroller doesn't set the speed the mount slews at during a goto. The motor comtroller board makes this decision independently for each axis based upon the amount of angular movement required to get to target.

EQMOD does provide a mechanism to limit the goto and parking speeds. This works by initialy setting the mount moving at a chosen rate until it is close to target and then issuing a goto (actually a series of iterative gotos) to bring the mount on target. Because by the time the gotos qre issued the mount is already close to target the slew rate applied is always slow. This is an 'advanced' feature of EQMOD (hidden by default) and should never be used unatended as any loss in communications between EQMOD and the mount during a goto could prevent EQMOD from stopping the initial continuous slew.

Chris.

[Merlin66]

Chris, Thanks for the clarification.