SS2k-PC froze - reboot took a while now PC says it can't see the handcontroller

[g__day]

I was doing a remote imaging run yesterday when I noted that things had hung - so I went to the astro lab and power cycled everything. The SkySensor2000-PC driving the Vixen Atlux wouldn't boot initially - it just beeped once!

I left everything off for about 5 minutes and tried again and it started okay. It was late so I just shut everything down for a day.

Today I booted first the Sky 6 Professional edition, then Cartes Du Ciel beta v3.012 then Cartes v2.76 - none of them can see my SkySensor!

I check the protocol was LX200 at 9600 baud on com port one with the usual settings. I tried a second laptop. I check the serial cable with a mutli-metre - all okay.

Has anyone seen this before - what is the fix or better diagnostics?

Do I reset the hand controller or try something else?

All my gear is protected on a UPS into mains are there diagnostics or a way to determine what has gone bad?

The mount itself runs off a 12 volt DC 3 amp regulated power supply being feed from a 500 volt amp un-interruptible power supply (UPS) powering PC Mount and a Canon DSLR 400D - with all of this being powered from mains.

Does this behaviour sound like insufficient quality power?

Its concerning to see no response - or rather error code 1400 from the Sky6 - nothing seems to be attached - check power and cables.

Don't you love it when things go weird! Hopes its something simple and cheap to fix - not a handcontroller replace or fix!

[Dennis]

Hi Mathew

I run my GPDX / SS2K combo off a 12VDC 2A regulated mains adapter and it has always worked okay so far. I guess you could try a re-set and then have to enter the Date, Time, Lat, Long, Time Zone again.

On the SS2K Yahoo Groups someone once had a problem where they could not connect and had to attempt it 20 or 30 times before it connected.

See message http://tech.groups.yahoo.com/group/ss2k/message/969

Cheers

Dennis

[g__day]

Dennis

I fixed it with a hand controller reset - yah and huge thanks all to the Yahoo SS2K group as well. The Handcontroller must have some clever protection and reset electronics inside it. Its fragile in some ways - but seems to have alot of protect circuitry and fall back recovery - which has proved excellent its there!

But now I ponder what caused it and how to avoid it in the future?

I tried plugging the mount directly into a Celestron 17amp hour PSU that provides a regulated 12 volts DC and up to 10 amps current - may have helped but it didn't fix things.

So next I just wrote down all the settings, powered off and recycles the hand controller (hold down all four direction buttons and power on). Interestingly this sets the gears and encoders all wrong - but I simply keyed in the previously stored values.

Then I set it to PC LX200 9600 baud and did a connect - worked first go on the Sky6 -> Vixen SkySensor2000-PC. I dis-connected the link switched to TeleAPI -> Maxpoint -> Skysensor2000-PC and re-conencted - worked beautifully again!

So all is well - until the next time.

What advice would folk give me - for instance should I switch to a regulated 5 or 10 amp power supply?

My chair in the astro lab sits on a plastic computer map with pimples down (to let me run over cables and to trap moisture under the plastic surface - works a treat). Should I place carpet over this? I wasn't even in the lab when things went wrong - I was remotely operating. So I wonder if a voltage spike happened somewhere - a long LAN cable?

All ideas very welcome - I'm smiling again!

[Dennis]

Hi Matthew

With the gear/encoder settings, make sure you set the correct sign (+ or -) otherwise you may find the mount will not track correctly in the S Hemisphere. Gerald just discovered this and apparently, buried deep somewhere in the SS2K Atlux manual, it explains this.

Cheers

Dennis

[g__day]

Dennis

Ah the lovely technacilities of this mount / hand controller! Yes I noted my settings where something like -060 180 -60 180 for RA and DEC (180 is probably teeth on the gears). On a re-start you get totally different values to correct.

I'm glad to hear Gerard is making progress - nwo I just want to understand what caused it to happen to me and how to avoid it in the future!

On the Yahoo SS2K group folk opinioned last light voltage drop (below 11.5 volts) or voltage spike (e.g. static electricity - strange as I wasn't in teh lab when it happened) could cause this.

Matthew

[Dennis]

Hi Matthew

The GPDX is values are +036x144 for both RA and DEC, where 36 is the gear ratio of the motor gear, and 144 is the gear ratio of the worm gear.

From my SS2K manual:
The worm gear ratio is also used in the PEC computation. The sign of the gear ratio represents the direction of rotation of the final gear. The default values for the parameters in this menu are set to the values for GP and SP equatorial mounts. The values may be changed if other mounts are used. For GP and SP mounts, please do not change the default values.

The change from +ve (default) to -ve (Atlux) for the gear ratios between the GPDX and Atlux settings :scared: were what caused Gerald quite a lot of grief recently.:(

Cheers

Dennis

[g__day]

Fixed that - pointing is again superb - now tracking is decent bar one spot in the gears where there is a noise and a slight jump - it seems regular once every rotation of the worm - any ideas?

[Dennis]

Hi Matthew

Again, speaking of the GPDX / SS2K combo, I went through 3 sets of MT2 motors with various problems, such as twitching and screeching, before Vixen sent me a 4th pair that have been working fine to date (some 10 years ago now).

The twitching manifested as a small jump where the object, initially centred in the FOV, occasionally “jumped” and then returned to centre, the movement caused by the RA motor throwing a wobbly. The initial solution offered by Vixen was to change the RA and DEC Set values in the Motor Parameter menu (Chapter 4 in my manual, under 4.7.3 Telescope Configuration Category).

The default values are RA = Set 1 and DEC = Set 1.

Vixen recommended changing these to RA = Set 3 and DEC = Set 3 and believed that this should fix the twitching. In my case it did not, although some SS2K / GP users said it did.

However, from what you describe, it doesn’t quite sound like the random twitching that I experienced.

Cheers

Dennis

[g__day]

No and it wasn't there in the past two months. Mind you today I switched from a regulated 12 volt 3 amp power supply on a UPS to a 12.3 volt 8 amp regulated PSU - may its that?

Maybe there is some gunk on a gear - can you easily clean gears or is impossible to service yourself?

Another thing when I did a hard reset - I saw no option on the V2.05 controller to select Atlux or GP mount - should I have?

I figure this is all fixable - if I can reveal the tweak I need!

[Dennis]

Hi Matthew

AFAIK, I think the only changes required, are to the settings to the gear ratios from the GP/SP settings of +036x144 to -060x180 for the Atlux.

The (external) GPDX motor casing with its brass gear, and the meshing brass gear on the end of the worm shaft, are a little exposed to the outside environment so conceivably, some foreign object could get in there and lodge in the gear train. I’m not too sure of how exposed the Atlux gear train is?

It might be useful to PM Gerald, as he has opened up the Atlux and so knows the internal configuration.

Cheers

Dennis

[g__day]

Dennis

Yep - have made those gear changes - I can try setting the RA motor mode from 1 to 2 or 3 - not sure how that will help. I'm pondering foreign body in the gear train too - maybe a bit of foam - there was alot of the white surf board foam surrounding this mount when it was packed - maybe some slipped it?

If it just needs a simple cleaning - I hate to have to send it to Japan for a 5 minute cleaning task!

Matthew

[g__day]

Well I set it to RA motor mode 2 (who knows what that does) but all seems very good, so go figure. I just wish all this capability was better documented.

Wish 2 would have been for Vixen themselves to release anASCOM driver that revealed the full capability of this mount / handcontroller. Its like they did all the work and then stopped at the last mile with the software.

[Dennis]

From memory, the problems that I experienced with the GPDX and MT2 motors seemed to be related to the “motor shaft tension” (Vixen words) rather than the motors themselves.

It seems that the motor shaft tension needed to be set within precise limits. If those limits were achieved, the values of RA = Set 1 and DEC = Set 1 worked okay. I understand that a “faulty” batch(es) of motors slipped through where the motor shaft tension was outside these limits and setting the values to RA = Set 3 and DEC = Set 3 seemed to “fix” most of these. I assume that these software setting changes caused the motors to be energised or activated in a different manner by the hand controller?

Anyhow, this is all GPDX and MT2 stuff, so I’m not sure if it applies equally well to the Atlux?

Cheers

Dennis

[g__day]

Denis,

A bit more research lead me to folks who basically viewed that the higher numbers equate to more torque and an increased period of deceleration when approaching goto target. This protects the gears and motors by ensuring a heavy telescope slewing fast doesn't come to an abrupt stop - thereby stressing the gears less.

So I set RA to 3 and DEC to 2.

Then I took off the face plate (4 screws) and the rear panel (2 screws and two Allen bolts) and watched a few complete revolutions of the gears. At one point in the revolution of two (I guess 60 cog gears - about the size of a 20 cent piece each) - the gears that move slowly and sedately jumped about 4 mm forward in a sudden lurch!

So I cleaned these gears very carefully with some tweezers a removed a tiny bit of gunk out of the gears and sprayed them with some high quality Lithium grease. Next I inspected the main gear and worm - it looked fine - in fact it looked beautiful. Next I let the scope rotate for about 30 minutes - this time there were no jumps or bumps - only a smooth revolution of the gears!

So fingers crossed it looks like things are much improved - and with any luck my next imaging run should be a lot less stressful!

As a final point I must say the built quality of the Vixen gear internals looks really high end - which is very preasing to their proud owner! Too having the confidence to open, inspect and clean the gears if I have to is a side benefit of increasing confidence. All those years with Mechanno as a kid must have paied off!

Matthew

[Dennis]

Hi Matthew

That sounds like you’ve got the problem fixed, which is good news indeed. Yes, Vixen gear (made in Japan) is excellent kit indeed.

When my GPDX/MT2/SS2K combo originally started misbehaving (back in 1996/7), I decreased the slew rate from x1200 to x700, and increased the ramp up/ramp down times from the default of 4 secs to around 6 secs and it didn’t appear to make much difference to the twitching and screeching of the MT2 motors.

However, the replacement MT2’s have been working fine now for approx 10 years.

Gerald is the real mount “break-in” man. He’s built various break-out-boxes and has been at the internals with a CRO!

Cheers

Dennis