A Cautionary Tale AZ EQ6/SynScan WiFi

[Split Zygote2]

A little long - sorry! This cord wrap issue may (or may not) happen to someone else and result in a less fortunate outcome. AND apologies if this is already a well known foible of the equipment in question - I did do a search with a negative result.

Formatting may be a little weird as I did a copy and paste from a word programme but see point 3 below!

Disclosure:

firstly, the mount - it is BLAMELESS (a statement of faith; we have bonded!)

secondly, what happed may on the one hand be the result of a unique set of circumstances that will not occur again before the end of time, yet on the other hand.......

thirdly, I am a Board Certified Muppet (Eldest Child's Opinion and possibly not wrong) - when anything related to computers or software is involved. Computers just know when you don't like 'em!

The mount (a mid 2016 example) was very recently upgraded by obtaining the SkyWatcher SynScan WiFi module, the SynScan App (Pro 1.11.3) which I run on an iPad Air (the first one) using iOS 12.0.1. This was connected to the dongle(?) generated WiFi to control the mount. I have used this set up for a few nights without incident.

I had set up outside on the patio and the mount was slowly tracking across some trees at a sidereal rate (it was daytime) as I was occupied in balancing some new equipment. The Wi-Fi module was plugged in, the mount in Alt-Az mode was being controlled by the iPad using the SynScan App alone (i.e. no planetarium programme or any other device was involved); power as usual was supplied by a fully charged Tracer LiFePO4 12V 16 Ah battery which typically supplies according to my meter around 14 volts over a 2 metre length of cable. All was well, however at this point my brother phoned to query some points in an e-mail that I had sent him.

Leaving the mount to do its own thing I went into the lounge via the French Doors, taking the iPad with me, sat on the sofa and loaded up the mail programme to review the mail in question - this doesn't require an internet connection.  It is unclear whether or not I shut down the Syn-Scan App (probably not) and I do not know at this point whether the iPad reverted to the Home Wi-Fi network (still on auto join) or stayed connected to the mount's. I suspect it stayed paired with the mount as the mount was much nearer and that is what it had always  done before.

After a short while on the sofa talking to my brother I became aware of a noise that sounded like a cross between a stationary, hovering camera drone and an angry hornet. The noise was strangely persistent and unchanging in character - so I idly walked outside to investigate.

The AZ EQ6 was in distress, not moving and with the power plug bent to an  unnatural angle as the motor strained against the power lead which was tightly wound several times around the mount. In addition my TeleVue 85 had seemingly been doing a fair imitation of a propeller as while it was currently motionless and horizontal it was upside down (very fortunately not hitting anything in the process). I cut the power released the clutches and manually untangled the cable. The plastic plug insert inside the metal plug housing screwing the power cable to the mount had fractured neatly into two (possibly by design) but otherwise based on subsequent testing the mount would appear as yet to be undamaged.  It could have been a lot worse.

In previous instances of briefly, absentmindedly and unintentionally exiting but not shutting down the Syn-Scan App nothing dramatic has occurred. Evidently on this occasion, in these circumstances and given the short amount of time that I was away from the mount, the mount seems to have moved at full slewing speed 'til it could go no more however hard it tried  - I would estimate based on the cable wrap 2 full revolutions or so - at the time I wasn't counting . As far as I am aware in a normal Go-To (and the mount was not left going to anywhere it was just left tracking) the mount obeys its software limits to prevent cable wrap (at least using the SynScan hand controller v4.something) and to intentionally recreate this situation I guess you would have to manually hold down the slew control until full cable wrap was achieved; self evidently I was not doing this. Whatever (a word I thought I would never use thus),  IT DID NOT FAIL SAFE.

The lesson learned is to maybe Hibernate (the App speak for Park) the mount  if multitasking with the iPad, better still not to multitask or if unavoidable to stay with the mount. 

At the moment and without further experience I would be reluctant to again leave the mount to its own devices when using this set up for control. The mount is in regular use carrying a heavy scope that requires 20 kilos of counterweight - had this been the case on this occasion it might have cost very much more than a new power lead.

Any thoughts or opinions would be welcome. Our nearest neighbours are SHEEP and although noisy on occasion I feel that they are unlikely to generate much in the way of RF interference. 

Thank you.

[Ronclarke]

A tale of woe certainly, I have had the WiFi dongle most of this year and apart from one incident which luckily disconnected the power lead from the mount it has behaved itself. 

As you say, better to hibernate if you can't see whats happening. I'm glad all your gear is OK and it's a lesson learned (for all WiFi owners!)

Cheers

Ron

[Split Zygote2]

Thank you Ron for your comments  and thank you Cornelius for your imput.

 

Michael

[Saibot]

Hi, yesterday I might have had a similar problem with the synscan app (Pro 1.14.0, Android) and the AZ-GTi mount. The phone briefly switched away from the Synscan AP to the home wireless network, I connected it as soon as I saw this back to the Synscan AP. The mount meanwhile was tracking the moon fine, the  Synscan App was still running, so I thought I can issue another GoTo to a star.

The telescope started to turn upside down, I pressed abort to not have equipment falling out and cables getting tangled. I suspect, the mount controller thought it was not pointing at the moon but back to initial North/horizontal direction and thus started turning completely wrong.
This happened after about 1 hour observing time and initial pairing of Smartphone + Mount.

So there might be an issue with the Synscan App and (short!) intermittent WiFi interruptions to cause a loss of orientation. Did others experience something similar? I reported it to the local (German) Skywatcher representative through the webform, he was not aware of this problem.

I will try two work arounds:

-use an older Smartphone which does not do the "Internet not accessible with this WLAN" check (I don't see an option to lock into only one Wireless on Android 8/EMUI

-remember to switch off the home wireless router before observing so that the home network is physically not available and the phone maybe will not even try to connect to it

Anybody else having this trouble lately?

-Tobias