Newbie... MC90 Telescope has something loose inside? Help!

[ExploringInfinity]

Hi I am brand new here, and brand new to telescopes. 

I got my dad an MC90 with the Ioptron Cube a few years ago, and it's never been used. Since he got it there has been something loose inside of the telescope and we've never been able to get it to work to look through it. 

Is there a way to open it up and repair whatever is wrong with it? its a 90mm lense, with f:1200mm. 

Neither my father or myself know anything about this, as it is the first time either of us has had one. It has been sitting and collecting dust for several years and it would be great to finally use it and so I thought maybe someone here could offer us some advice. 

Thanks so much for any help!

Edited April 21, 2021 by ExploringInfinity

[happy-kat]

Hi

I see that it is a Maksotuv telescope by design. When you adjust the focus knob the distance of travel on these is quite long from each end of the focus range so can be many many turns of the knob. Point the telescope at a very distant object (no where near the sun) use the eyepiece with the biggest number as this is the lowest magnification and slowly turn the focus knob all the way from one end of travel to the other. If you did not find focus then did you notice the mirror plate inside the telescope look closer at one end of focus travel then the other. If you did not then the rattle may be a uncoupling of the mirror to the focuser system. It goes together like, telescope / diagonal / eyepiece

Edited April 21, 2021 by happy-kat

[Pixies]

The ioptron has a flip-mirror diagonal built-in, I think. It might be this that is making the noise?

[Cosmic Geoff]

18 minutes ago, Pixies said:

The ioptron has a flip-mirror diagonal built-in, I think. It might be this that is making the noise?

And preventing anything from being visible via the eyepiece, if in the wrong position?