Help please - with an iOptron 8408 h.c.

[Adreneline]

Hi Everyone.

I am having problems with my CEM25-EC, in particular it is not tracking in RA correctly.

With the fantastic help of Alex and the team at FLO and feedback from iOptron I have made some headway in trying to figure out what is wrong, summarised in this nine frame (300s subs) video:

If the -EC mount was tracking correctly there would be no drift.

PA was achieved using a PoleMaster and confirmed with an ASIair. For the last four years the mount has worked perfectly unguided with my Samyang 135mm + ASI183MM - this problem has all started in the last six weeks.

What I really need to try is swapping out the handset, the reason being that the RA Guiding setting on my handset seems to randomly change itself from "Filter" to "Allow" with no intervention from me. The view is this is either a problem with the handset of a problem with the Main or RA board - or both! I am reluctant to buy a new handset only to find it does not solve the problem so I was wondering if anyone happens to have an 8408 hand controller they are not using or would not miss for a few days (weeks depending on the weather). I have already replaced the handset battery although the view is that this should not have had any effect on the RA tracking.

I have already thoroughly cleaned and re-greased the mount. Slewing to a target always works perfectly. I have recalibrated the encoder several times - it always completes as expected. I am sure the encoder is working - the problem seems to be the that something in 'the system' keeps changing the handset to "Allow" - i.e. allow the RA axis to be guided and effectively disable the encoder. I have tried to guide using the ASIair PHD and NINA PHD2 but that results in erratic performance of the mount with an RMS in excess of 50" and a graph that looks like the Alps!

All communication with the ASIair (or a PC running NINA) goes to the mount via the handset and its connecting cable. On occasion the RA axis will stop completely or intermittently which just to add to the complexity of the problem.

I am clutching at straws!

If anyone can help with the loan of a hand set I will of course cover the cost of shipping in both directions.

Thanks for reading this.

Adrian

P.S. If the handset is not the problem I appear to be faced with sending it back to China for an out of warranty repair - not an attractive proposition.

Edited October 27, 2023 by Adreneline

[Gary Clayton]

Have a word with Altair Astro as they do Ioptron repairs in the UK