SkySensor 2000 poor alignment issue

[ilife13]

I am hoping somebody can give me some advice here, this is my first thread.
I purchased a Vixen GPD2 mount with the SkySensor 2000 hand control through the IIS classified adds some time ago. Everything was working well initially and was aligning the scope with good accuracy. After lots of cloudy weather and an overseas holiday it was some months when I finally got my scope out again and I took it into the country. However since my last session, the battery in the hand controller died and I had to replace it. No big deal as I am fairly handy as the battery requires soldering in place (correct battery Purchased). I reset the time, location and time zone in the controller (double and quadruple checked since) however, when I do a reference star the scope points absolutely no where near the selected star (40+ Deg off). Even manually slewing to the star and pressing "align" (for the 3 seconds until it beeps to accept the star) is of no help as when I chose a second reference star it will go in the opposite direction to the second selected star. Is there something obvious I am missing or other additional information that needs to be reset in the hand controller?
I have been through the SS2K user guide and checked everything I can but there are some settings that I do not understand and are not explained in the manual. My current set-up is Orion ED80T CF and Vixen VC200L (not that this will make any difference to the solution).
Any help or advice would be greatly appreciated.

David

[blink138]

I am hoping somebody can give me some advice here, this is my first thread.
I purchased a Vixen GPD2 mount with the SkySensor 2000 hand control through the IIS classified adds some time ago. Everything was working well initially and was aligning the scope with good accuracy. After lots of cloudy weather and an overseas holiday it was some months when I finally got my scope out again and I took it into the country. However since my last session, the battery in the hand controller died and I had to replace it. No big deal as I am fairly handy as the battery requires soldering in place (correct battery Purchased). I reset the time, location and time zone in the controller (double and quadruple checked since) however, when I do a reference star the scope points absolutely no where near the selected star (40+ Deg off). Even manually slewing to the star and pressing "align" (for the 3 seconds until it beeps to accept the star) is of no help as when I chose a second reference star it will go in the opposite direction to the second selected star. Is there something obvious I am missing or other additional information that needs to be reset in the hand controller?
I have been through the SS2K user guide and checked everything I can but there are some settings that I do not understand and are not explained in the manual. My current set-up is Orion ED80T CF and Vixen VC200L (not that this will make any difference to the solution).
Any help or advice would be greatly appreciated.

David

[g__day]

I have used a Vixen Atlux with SS2K-PC for about 7 years now - so hope I can help you!

Things to check.

Power on settings - you can have 10 defaults (in case you like to go to up to 10 different observing location). Are you just using power on selecting location one each time? I presume you do and then you Press Enter to reset all coordinates (rather than ESC to use last alignment parameters) or doing something else fancy?


On power up the scope should be level and facing dead East at the horizon - elevation 0. Press Enter (rather than Esc) to initiate a new set up. Then go to Setting and wander through location and time first.

Dates - make sure your enter the coordinates in yy/mm/dd format.

Entered your time zone (+8) correctly and local time hh/mm/ss (noting hours is a 24 hour clock so 10pm is 22/00/00).

Location - Longitude and Latitude - make sure your get the +/- for West / East and South / North entered correctly! Enter Longitude and then Latitude - with Southern Hemisphere being negative Latitude and Positive Longitude!

Sydney is 33 South 151 East so is entered +151 10 00 -33 08 00

Perth is 31 55' 33" South and 115 50' 18" East from your avatars location so is entered +115 50 18 -31 55 23

Gearing - mine is -60 180 -60 180 - the minus before the sixty tells the mount which way to spin the gears as we are in the Southern Hemisphere! This tells the controller the motor gear has 60 teeth and the other gears 180 teeth.

Motor settings - if you scope is heavy for you mount - choose option 3 on both RA and DEC! This runs the motors a bit slower and more smoothly on slews. A very light set up might choose Option 1 for both axes.

Polar alignment mode - if its in an observatory and well polar aligned makes sense to run it in polar aligned mode - else select Polar unaligned if you are in the field.

First alignment point - can be the Moon Centre if you don't know the 32 reference stars. Once you have a one star alignment (by dead centre the object on the target and holding the align button for three seconds until the controller beeps) select one to two more well spaced reference stars and then see how close the go to is if you go back to the Moon!

* * *

That is the basics of set up - even 20 degrees off polar alignment once you have 2-3 reference stars both go tos and tracking should be brilliant. Go tos should be within 30 - 60 arc minutes at worst and tracking can be brilliant - unguided up to ten minutes with no star trails.

Provide a bit more detail about exactly what your power on sequence, check list and SS2K settings are and I can possibly help more.

PS

Also check your PSU is delivering at least 12V and 2-3 amps - I use a regulated Lab power supply to give 15V and 5 amps - overkill but my unit only draws what it needs!

[brian nordstrom]

:shrug: Seems strange David as these are usually bullet proof , I think you would get a better response to your query in the 'Equipment Discussions' section .
One thought , does the settings state , D/M/Y ( day/month/year) like we use or M/D/Y like the Americans use ? lots get caught out by that .
Brian.

[ilife13]

Thanks for the thought Brian. The SS2K lists Y/M/D and this has also been quadruple checked.
My brother has listed this on equipment talk on my behalf.

David

[brian nordstrom]

:D Ahh , so you are Pat,s brother I look forward to meeting you.
Also have a look at Yahoo groups 'Vixen" , They will be able to help you these groups are like IIS and I am sure they will have heard of this problem before.
Good luck.
By the way I love your set up , very nice.
Brian.

[ilife13]

Matthew
Thank you so much for spending the time on your extensive response, I really appreciate that. I think you may have hit the nail on the head regarding the gearing as it was at +31x144 (I assume a default setting from the battery failure). I entered what you said and I think one of the motors kicked in suddenly after pressing "enter". This, I assume would also explain the scope coming to a stop and reversing (without any danger of the scope hitting the mount) as it did the other night.
Thanks again, I realize you put some time into your response. I am now looking forward to tonight.
I will keep you posted.
P.S. Just to explain, my brother (Blink 138) posted this on equipment discussions on my behalf as I only posted it on beginners talk.

David

[ilife13]

Matthew
I have the MT-4 motors which after checking online has 144 teeth which is as it was set up. I am not sure about it having 31 or 60 teeth on the motor however. I will do more research on that. The set up was still plus instead of minus so fingers crossed for tonight.
Thanks again
David

[LewisM]

I think the MT4 actually has 40 teeth on the motor

[ilife13]

Thanks Lewis for your help. It sounds like the original gear settings where correct except the plus and minus. It is actually 36 teeth on the motor (my mistake when I said it originally showed 31).

Thanks Brian, I will check the Yahoo groups as you suggested. I am sure I will meet you soon.
I will post the (hopefully positive) results tomorrow.

David

[ilife13]

Matthew
I guess I got a bit excited thinking the issue would be resolved with the gear setting. It didn't work. So my settings are as follows.
Mount pointing South (I have holes in the paving outside for the tripod legs, the scope in the horizontal position and pointing East ( 0 deg el).
It should be noted here that I use a side by side plate but the scope is still pointing East as per users guide.
On powering up I select "0" default value then "enter" which has my home coordinates set. Date and time are set as YY/MM/DD and using 24 hour format and +08 time zone. Location is set at +115 48' 53" (Lon) and -31 55' 35" (Lat). Gearing was checked with my manual at 36 x 144 for both RA and DEC ( note that when I changed the + to a - the motors the slewed the wrong way). I had to revert back to positive for correct rotation. Motor parameters are now set to 3 as per your advice on heavier equipment. I am in "unaligned equatorial" mode.
My first ref star for alignment (Rigel Kent) was way off but I used the hand control to centre the star and pressed align until it beeped. I then pressed esc to choose a second ref star (Antares) which again went no where near but the mount slewed in the correct direction. I persisted and centred Antares and pressed align until it beeped but this time it still said "one star align" and not 2. My third reference star was Vega and when I pressed "goto" the scope slewed in the opposite direction to Vega and stopped pointing almost 180 deg away (South instead of North). At this point I went back to Antares which was fairly accurate ( very close to centre in the eyepiece). In the set up menu there is "PC Protocol" which gives me the option of SkySensor 2000, Ultima 2000 and LX200 and several values for "Baud". In my frustration I tried all 3 options and reading some blogs online it appears that it should be on LX200 (not SkySensor 2000) and 9600 Baud. My mount is Vixen GPD2.
Any further thoughts?

[Terry B]

I owned one of these in the past. I remember that it didn't work on SS200 setting and you needed to use the LX200 setting to work.
Worth a try

[g__day]

David,

A few things, is it a SkySensor2000 or a SkySensor2000-PC?

If it has a port on the hand controller thus allowing you to connect it to a PC with the right cable then I'd say it's the PC version, in which case always select the LX200 protocol and 9600 baud and it will likely be picked up on your controlling PC on COM1 port.

What EPROM version are you using - when it powers on it should say something from Version 2.05 -> 2.10. Which version are you on? Version 2.04, 05, 06 and 2.10 use MT4 motors, versions 2.07, 08, 09 use MT3 motors.Latest update EPROM is 2.10, however 2.10 cannot be used with the MT3 motors.

The versions prior to 2.08 were a bit buggy with reliably establishing the PC connection, whereas I have never had a fail connecting since upgrading from version 2.06 to 2.10. A guy in Hawaii still has spare of the 2.10 EPROMS if you wish or need to upgrade I can pass on his contact details.

When you issue gotos - do you do it from the hand controller or a connected PC control program? If its not the SS2K itself where you are selecting stars we should know - as this can be confusing things if the astronomy program isn't set up correctly (e.g. location, date, timezone or local time is wrong).

Gearing - for me using EPROM v2.10 it asks on a battery re-instal am I a controlling an Atlux or a GPD2. The gearing comes from that decision point. You can over ride, for a GPD2 I would expect your Gear ratio settings have to be (from page 67 of the manual - which I can send you):

-36 144 -36 144

Get this wrong and everything you have encountered is to be expected. Triple check this with others and the Yahoo group please! Re-reading your experience makes me initially think the mount believes it is in the wrong hemisphere - for reasons I am trying to understand given your Latitude is correctly set as South denoted as a negative number. Please recheck you don't have Lat and Long entered as each other - that too would account for the strange behaviour. The tracking being correct for a negative Lat with a positive RA gear ratio doesn't make sense to me - again a sign of hemisphere reversal.

Your first slew should not be be "way off" - can you please qualify - how off is it and in which direction? If your first slew was to the Moon - how far off would you say it is.

I generally doesn't choose a reference star near the South Celestial Pole, Antares might be a better first alignment point. With a One star alignment - if you go into settings, Polar Axis Direction - what does El (elevation - which should be your latitude ~31) and Az (Azimuth) read.

Also in Settings please check that Encoder Menu settings are selecting Internal (I) encoders not external Encoders (E). It should read I (+0400 +0400). If you set External encoders the SS2K ignores the position read outs of the mounts internal sensors!

Matthew

PS

Really dumb questions here, to rule out the naivety errors sorry - I am just trying to be exhaustive in my check list - not offensive! So:

1. When you say the Scope on set up is facing due East - you do mean the front of the scope where the light goes in correct?
2. The Mount is level and the head of the mount is elevated to around 31 degrees above the horizon correct?
3. The Mount is pointing South - so the rear (lower end of the Mount head) is facing due North and the high end of the Mount head looks due South?
4. In your settings menu - Telescope Configuration, Motor Key Direction Up arrow, down arrow Left and right are respectively mapped to N S E and W?

[g__day]

Just took down all my settings - compare if that helps:

SkySensor2000-PC Settings

Power on Shows SS2k v2.10

<ESC> takes you to Setup

<0> <Enter> takes you to Default settings showing Location and time first screen is Location showing Longitude Latitude

Long Lat +151 08 00 -33 47 00 ..............................NB +151 07 09 and -33 47 28 are the correct values!

<Next> takes you to Date YY/MM/DD HH/MM/SS Time Zone
14/09/20 12:46:07 +10 ................................... .....NB PC 10 secs slow, SS2K 2 mins 10 secs slow!

<ESC> takes you up a menu level, <Next> takes you to Telescope Config

Setup Categories Telescope Config
Encoders I(+0400 +0400)
Gear -060x180 -060x180
Motor Parameters RA = Set 3 Dec = Set 3
Polar Axis Direction El=(33.7) Az=(180.2)
Alignment Point 2: Spica 1: Rigel Kentarus
0-433 +315 +000 +000
ETC Key Definition Sky Tour Mode
Init Motor Ctl Mode RaDec
Spd: Fast Med Si 0000-1200/4/4 32 2.0
Key Ctrl N-S E-W
Backlash RA=000 Dec=040
Mount mode Polar Aligned Equat.
PEC On 0.5 Execute
Autoguider On RA=+0.5 DC=+0.5
PC LX200 9600

[ilife13]

Matthew
Just got home so I will deal with your first reply first.
By the way, if you ever come to Perth I owe you a night on the town (as small as it is). I really appreciate your time and effort on this as it is driving me mad. The worst of it is, I sold my Celestron CG5 mount to get this one. The CG5 mount would not polar align and I finally got confirmation from Celestron that the CG5 had issues in the southern hemisphere. I fought with that mount for nearly 2 years as the polar alignment is critical for astrophotography. I am starting to have flashbacks of that mount. Sorry to ramble on.
1. It is the SkySensor 2000PC. Although it is not connected to a PC except for guiding. PC protocol LX200 and 9600 (although I did try all of them in frustration)
2. It is the version 2.10
3. Stars are selected from the hand controller (I usually select the stars from Stellarium prior to starting).
4. I have checked the gear ratio from the user guide (page 64 in my book) which says +36x144 +36x144. Interestingly when I changed these values to negative the motors slewed in the wrong direction on the first reference star so I reverted back to +.
5. The first reference star was Rigel Kent. The elevation was far too low and Dec probably 40 deg out. It did head in the right direction but no were near far enough.
6. I will take it out tonight and advise later on Antares as the first reference star.
7. Confirming internal encoder and I+400 +400
8. Also confirming the scope pointing East as you say.
9. The mount is levelled with spirit level and elevated approx 32 deg.
10. The mount is pointing South with lower end pointing North.
11. Motor key control exactly as you stated (up, down, left, right, North, South, East and West).

Thanks again

David

[ilife13]

Matthew
I fear the problem may be severe.
The set up configuration are as follows.
Encoders I(+400 +400)
Gear +36x144 +36x144 (a minus value slews the scope the wrong way)
Motor Parameters RA = Set 3 Dec = Set 3
Polar Axis Direction El=(32.0) Az=(180.0)
Init Motor Ctl Mode RaDec
Spd: Fast Med Si 0000-1200/4/4 32 2.0
Key Ctrl N-S E-W
Backlash RA=000 Dec=040
Mount mode Polar Unaligned Equat.
PEC ? (cannot find in the menu)
Autoguider On RA=+0.5 DC=+0.5
PC LX200 9600
When using Vega as first reference star the scope points SSW instead of North and elevation was around 45 deg (far too high). At this point I decided to "trick" the scope by loosening the clutches and centreing Vega in the scope and pressed "align" until it beeped. I then went for a second star (Antares) and the scope slewed to North-West with an elevation of around 50 deg instead of West. Then when I tried to use the direction keys to centre Antares the motors were very inconsistent (at one point while pressing one button the second motor kicked in and it slewed diagonally and on another occasion it would only slew in Dec even when pressing the RA buttons.
Interestingly, the coordinates in the hand control for each star matched those on Stellarium in every case. The clutches are tight and I cannot detect any slipping at all.
When I did manage to centre a second star (with excessive correction on the controller) the scope still said one star align and not two. If I move away from my one star align and go back to that same star it does it with fairl good accuracy (although not perfect).
I am totally lost and very frustrated.

[g__day]

David,

PEC won't appear I believe unless the mode is set to polar aligned.

Such wrong slews at the beginning point to something well out of order. The only thing that makes any sense to me is thinking Lat and Long is wrong. Now if your Gearing has changed to needing +ve instead of -ve values on the gears have the signs changed anywhere else?

Your set up seems textbook. I would recommend:

1. Checking how it tells you to enter Lat and Longitude settings
2. Do a full reset - on power on hold all four direction buttons down for 5 secs until it beeps and then re-enter all values
3. Post on the Yahoo Group SS2K - get Chris Erickson or Laurie Yates attention - they are the best

Do a test for me later on.

First

When the moon is in a convenient location - say 45 degrees above the Eastern horizon - do a goto and align on it first and note how far off is the set up.

Second

Go to a star say 5-10 degrees away from the Moon - see if it moving in the correct direction by the correct amount.

Using this information let's see if we can diagnose if its something very simple like the initial orientation on start-up is somehow is confused (for whatever reason)!

For instance if goto on the Moon (or any star) elevated to 45 degrees above the East does anything else but raise the mount in RA by 45 degrees gives us something to think about.

* * * * * * *

If the first goto from a 45 degree elevated due East target moves in the wrong direction or wrong amount it will tell us a lot. If the magnitude of the move is correct but the direction is wrong / inverted it tells us the location data is inverted / screwed! If the magnitude of move is wrong then things are worse - it would indicate data on star's position appears wrong / corrupted.

When you set the Mount up to be due East and level - and control everything from Stellarium (it can do this) or the freeware CDC (Cartes Du Ceil) and you issue commands from the PC does it seem to run things correctly? If you say elevate 25 degrees, move East 30 degrees, descend 10 degrees, move West 50 degrees etc - does the mount respond correctly?

If a PC program talking to the SS2K-PC controlling the mount all works fine that is more data we can use.

If all gotos are correct in magnitude but inverted or wrong in a consistent direction - then that is location / set up data to correct. If gotos are random or wild - there is a deeper problem with the SS2K (and I would send it to Chris in Hawaii as he would be your best chance of fixing things).

I know how frustrating this is and feel for you. These things are tanks that are supposed to never fail! That has been my experience once you get the hang of it.

Love to have a beer or two with you if I ever get to Perth!

Do you have a cable to control the SS2K-PC from your PC - will see if I have a spare if you don't.

Matthew

PS

The tests on moves can be done roughly during the day with the mount facing direction. If the mount thinks its aligned and pointing at a subject - anywhere - and you wish it to move say 10 degrees up and 5 degrees West (controlled either by PC or from the hand controller) by selecting the right targets - what does it do? If gotos appear precise (even if inverted) - we just have to work out what the correct start up orientation would have to be and use that.

It could be a simple as you (somehow) have a version that requires the mount to face due West on first start-up (the way folks in the USA must) and all might be well.

PPS

Confirm how you are powering it - a decent power supply is a must. And check the connectors polarity is correct - the SS2K's 12V power input is unusual compared to everything else on the market (cigar lighter with positive centre I recall - need to check that)!

PPPS

Post a picture or two of your rig!

PPPPS

If you align on any star - then use the RA DEC display to point the mount to where it thinks due East and Elevation 0 is - where is it actually pointing?

Did the original owner of this gear report any similar issues? Was the SS2K originally using the V2.10 EPROMS or did he upgrade it? (Just checking he didn't upgrade V2.07 - 2.09 to 2.10 - as that would be mixing MT-3 motors with the MT-4 controller - a big no no!)

[ilife13]

Matthew
I will check all of this as soon as I can.
It is very interesting what you said about the mount being set up to point West (although I have never heard of this before) because whilst trying to goto the first reference star I actually thought that if the mount was pointing West instead of South it would actually be close.
I will try the full reset as you suggested as a first step.
Thanks
David

[ilife13]

Matthew
The SS2K will not reset. Is there any other way?
When I power up and press all 4 direction keys the motors start up but nothing else happens even after 20-30 secs.

David

[g__day]

David,

I will re-check the manual - did you have all four buttons pressed before you powered on?

Normally just disconnecting all power for 5 minutes trips the first level of reset from memory - but doesn't clear config settings - its the first level of protection.

Matt

[ilife13]

Matthew
Cancel that last request, I should have the direction buttons pressed before powering up. I have reset and re-entered all information.

David

[g__day]

Okay

Now do suggest you do a few tests as described where its convenient, can be inside. Fire up your astronomy program Stellarium and choose say the Moon as alignment target one.

Align on the Moon
Goto Mars which is only a few degrees West - see what it does!
Goto Saturn - which is about 20 degrees East of the Moon
Goto M68 - which is about 15 degrees SW of the Moon
Goto M104 - which is a South and West of the Moon about 5 degrees
Goto Acturus - which is about 20 degrees due North of the Moon

Note your offsets using your hand controllers X/Y or RA/DEC settings - is it traveling the correct magnitude and in the correct direction?

Cheers,

Matthew

[ilife13]

Matthew
Yesterday (daylight indoors) I attempted some of your suggestions and the results are:
I chose the Moon as a first reference and the scope slewed to point South instead of North (although the elevation was roughly correct). I then chose Vega as a second reference and the movement from the Moon would have been roughly correct.
On a separate start-up (after switching of and re-setting to the start position) I chose Antares and although the scope slew in the right direction it was still 40+ deg out. I did several shut downs and start ups and something stranger happened. On every second start-up, as soon as I pressed "enter" after being prompted to set the scope horizontal in the start position it immediately slewed clockwise at full speed on the Dec motor. The scope slewed about 40-45 Deg before it stopped and if I pressed the stop button during this unprompted slew, it would stop for a couple of seconds and then immediately start again.
I use a battery pack which I am sure is fine but I will check it as I can't afford to leave anything out. I do not have a cable to operate the scope from my computer but I think I should buy one to eliminate that as a possible solution.
I also reset the gears from + to - as you have indicated they should be negative for the southern hemisphere but the motors definitely run the wrong way. This was done after the scope slewed South instead of North for the Moon. When I did this, the scope did slew to the North as it should but it pointed below the horizon. Remember that other reference stars did slew in the right direction with the gears set to positive. There seems to be very little consistency if not random in slewing to various objects. Although the hand controller displays the positions of these reference stars and the Moon correctly (same as Stellarium) everything is extremely mixed up.
One thing to remember is that this mount was working fine initially but after several months of poor/cloudy weather and me being away overseas, when I came to use it the next time I took it to the country for dark skies only to find that the battery in the hand controller had died. As it was only one night I didn't spend much time trying to reset it. I ordered a new battery (which was the correct one) and was fitted to the controller (also done correctly, I am confident) and it hasn't worked since then.

I will do some more hopefully tonight and give you more answers to your questions and suggested procedures.
PS. I have taken a couple of photo's of my set-up but I don't know how to add them to this post.
PPS I have checked to make sure Latitude and Longitude are set and in the correct order.
PPSS I tried the pointing West set up to start but it is no better.

Best Regards
David

[ilife13]

Matthew
Further test results below. Starts with Formalhault as it is pretty much due East (same as scope start point). In each case the SS2K hand control displayed coordinates matched those on Stellarium but pointing accuracy deteriorated as it slewed from East to West to North moving less and less each time and in fact only getting as far as South for Altair which is actually North. Slewing was consistent (consistently poor) as I returned to the same reference points.

Formalhault
Appr slew position/Actual Approx Alt.Az/Actual Alt.Az
East / East +22Deg / +48Deg
Achernar
South East / South East +13Deg / +26Deg
Rigel Kent
SSE / SW +22Deg / +34Deg
Saturn
South / West +32Deg / +26Deg
Vega
SSW / NNW +44Deg / +17Deg
Altair
South / North +35Deg / +49Deg
The next set are repeated a short time later to check consistency.
Formalhault
Appr slew position/Actual Approx Alt.Az/Actual Alt.Az
East / East +25Deg / +51Deg
Achernar
South East / South East +16Deg / +29Deg
Rigel Kent
SSE / SW +25Deg / +32Deg
Saturn
South / West +30Deg / +22Deg
Vega
SSW / NNW +44Deg / +16Deg
Altair
South / North +38Deg / +49Deg

David

[ilife13]

Matthew
I managed to find the instructions on uploading images.

[g__day]

Okay - some weird behaviour there alright

A few more things to check.

1. How are you powering it - what is the Voltage / amp rating of the source of power to your gear?

2. Can you check the power supply with a Voltmeter - even the $9.95 ones from Jaycar or Dick Smith are fine for this task - do they match rated voltages and ampages - check its not a faulty power cable into the mount causing a voltage drop

3. Are the pins from the SS2K to the mount all fine - none corroded or bent on the hand controller - no lint in the cable messing up a signal?

4. Have you asked if anyone around you has a spare SS2K you can borrow for a night to confirm its the hand controller - not the mount - acting strange?

5. You are dead certain the new battery is of the correct rating, orientated correctly and well soldered to the unit? Did you test it to confirm it was okay before you soldered it into position? Did you use minimum heat and/or heat sinks (i.e. alligator clips) when you unsoldered the old battery and re-soldered the new?

6. Everything fitted together well - and all spacers and insulators were re-inserted when you fitted the SS2K back together after changing battery - i.e. nothing was obviously touching or shorting between the two boards?

I think it might be time to definitely describe this situation to Chris Erickson who moderates the Yahoo Groups SS2K board and ask his views

https://groups.yahoo.com/neo/groups/SkySensor2000/info

and/or

https://groups.yahoo.com/neo/groups/ss2k/info


Will think some more of what else to try next!

[ilife13]

Matthew
Power supply is a 900amp 12v jump starter. I have a multimeter and will check it tomorrow.
All pins and connections appear fine nothing bent, dirty or corroded.
I will have to check or post another thread to see if anyone has a SS2K hand controller in Perth (a very good idea).
The new battery was correct and I was aware of overheating with soldering/desoldering and made sure the new battery came with tabs as it was available both with and without. I will open it up again and inspect it. I have retained the old battery and will compare them just in case.

Thanks again

David

[Visionoz]

David

Ensure that the cables that connect to the motors are indeed correct for the purpose ie; the RA one to the RA motor and the DEC one to the DEC

HTH
Cheers
Bill

[g__day]

David,

Not sure how much power your mount likes - mine specifies to give it at least 12V 2-3amp, I give it 15V and 5 amp through a Lab Power supply plugged into an Online UPS 1500VA -> mains. It will only draw what it needs I am told!

Must read up on your mount some more, as I am more familiar with the Atlux, but the behaviour you have described doesn't fit a pattern I am used to - so its most interesting. I keep asking myself what am I missing that would make sense of all this. As stayed bfore the SS2K is simply a tank - its the most consistent bit of kit I have ever experienced.

Bill's suggestions made me realise I don't know the cabling for your mount so I must review that; the Atlux has all internal cabling - you just supply power and one cable from the SS2K to the mount itself.

Really want to help solve this one!

[ilife13]

Matthew
Original Battery from the hand controller was Tekcell SB-AA11 3.6V.
Replacement battery is Saft LS14500 3.6V (equivalent according to Battery World).
I tested the original battery and it is absolutely dead. The new battery shows 3.64V. The connections were also tested.
My power pack is a staedy 12.89V.
All plugs checked, made sure the inside of the hand controller was free of debris and nothing touching that could create a short circuit, tested the cable from cigarette lighter Plug to power box on the mount ( the box on the mount sends power to the two motors).
I think I may need to check this box as it may be either faulty or sending intermittent power to the motors.
Although I didn't find anything obvious I reset the scope and tried again and there is no change.

David

[g__day]

David,

So its very consistent - just wrong...

The battery sounds find - and I'm glad to hear you took the right precautions with the soldering!

I forgot to ask - is tracking fine? If you are polar aligned and you get to your target does it keep it centred well? I expect it shouldn't but will not be surprised to hear it does. Tracking is just real time pointing - and your pointing model seems to be confused - for no fault of your own.

I think it is definitely time to see if you can find someone with an SS2K and see if your unity can run their mount correctly and vice-versa - to isolate the fault to cabling, mount or controller.

I don't like that some goto's had wierd track or unrequested slews - that is exceedingly strange and needs to be isolated and resolved.

Slightly beyond my knowledge - if you were to remove the battery completely - I believe the the hand controller still power on and operate correctly once all parameters were re-established. A pain in the arse but could allow you to do more diagnostics.

I would say join SS2K and SkySensor2000 Yahoo Groups and post your questions and the background data shared here with that user base and you will have a few hundred more experience folk on your side. Whilst I also ponder what is next.

Matthew

PS

This is totally wrong - but what the heck - try changing the sign of the Lattitude from negative to positive, restarting the controller so the hemisphere change takes affect and see if gotos are affected in any (hopefully positive) way. Then revert back to -ve lattitude and reset again and see if the behaviour changes.

Playing in my mind are two scenarios - somehow the location data which must be Southern Hemisphere is confused - or there is a incorrect feedback loop somewhere (a short in wiring, dirty voltage or an optical encoder with muck on it). I pondered would flipping the polarity on the Lattitude trip something and get it to reset correctly!

[ilife13]

Matthew
I will work on the Yahoo groups and let you know. I opened the grey power box that powers the motors and it looks like it has been opened previously. Some dodgy wiring/soldering but the connections were OK. I did change the negative wire as it was joined and soldered with mesh around it for insulation. Very strange and it is only 3 inches long. I changed it to a single wire and resoldered it. Didn't change anything though.
Further test results follow.
Set the OTA's to point South instead of East (due to the fact it doesn't seem to want to go as far round as North). This was done during the day so it was approximate.
First reference star Sirius and it looked very good both direction and altitude.
Second was Regulus and this also looked very promising (I was trying to gradually get to North). Third star was Arcturus which is when it went wrong (it ended up pointing South instead of NNE. Then back to Regulus which again looked good, followed by Jupiter which also looked fairly good.
I then tried both the Moon and Venus. The scope beeped and advised they were too close to the Sun (this was also correct at the time of testing).
I have tried reverting the gears to -ve (even one motor at a time) but the slews are going in the wrong direction.
Because of the poor alignment, I haven't checked the tracking and the last few nights have been raining or overcast.
David

[ilife13]

Matthew
Just thought I would bring you up to date.
I have registered with Yahoo groups for the SS2K. I had to open a Yahoo account and apply to the SS2K forums which has now been accepted. I have had plenty of input (all appreciated of course) but so far nothing new to report. I tried to get them to read the IIS forums to save some time as you have had so much input and suggestions but I am not sure whether anybody has done so yet. It is amazing the amount of people that are willing to help and give advice. I hope I can return the favour to all of you some day.
Will keep you posted on any results.

David

[g__day]

David,

It's a very helpful group - and I am sure they will ask you to check things I had assumed would be okay - it will just take them a while to get up to speed.

The key summary I would suggest you give them is simply:

1. Everything worked great until a battery change
2. Battery change itself seems fine
3. On re-initialise all parameters appear correct (and can be summarised for them)
4. Pointing seems to be horrendous - and it gets worse in certain quadrants of the sky.

That should give more experienced minds than me something to diagnose from. It should also trigger a check if anyone else has seen similar issues and knows the cause and fix.

Do ask if they know of any SS2K users in your geography!

I expect they will wish you to confirm wiring seems okay and confirm no blown circuitry appears evident anywhere in the hand controller or mounts motors.

They will likely wish to know if tracking after a one star alignment is fine or horrendous.

If diagnosis is very hard to do I would ping Chris Erickson in the Group out of Hawaii to have a look a the unit if he thinks that might help.

Will look for you on those groups and see if I can contribute ideas too!

Matthew

PS

Posted there in the Yahoo forums in your thread for the above summary and my view you have set up the controller correctly.

PPS

Would love you to get a PC cable and see if after a one star set up, would any goto commands from an astro control program suffer the same or different consequences from entering the same goto from the hand controller. I am starting to ponder if your co-ords match an astro programs coords then encoders appear fine, so it may be something exotic interfering with gotos.

If you lock on one star then issue a goto a second star which fails badly - then issue the same goto again once or twice een does the mount move at all or think its already on target? If you then press the ID button on the controller does it search and find your target star or report its a long way off? If it finds your target star in th ID function are its coordinates correct.

I do feel we are still making progress!

[g__day]

Just a brief note on progress, after 49 posts relating to this on the Yahoo Groups page https://groups.yahoo.com/neo/groups/SkySensor2000/conversations/messages/745

Folks are definitely puzzled by pointing worsening significantly as the mount heads West. Trying to determine if its more likely to be the Handcontroller or the mount.

My latest thoughts are on errant gotos run the SS2K ID function to see if thinks it is on target or if it for unknown reasons (incorrect slew limits caused by a location error in Lat or Long) halted the slew early.

Some progress but wish there was another SS2K user around David's location to speed up the process of elimination as to the root cause of the issue.

[ilife13]

Matthew
I have been out of action for a while but have spent half the day on this nightmare of a mount.
I believe the problem is two-fold.
Firstly, a man from the Yahoo groups indicated he had some similar issues when he changed the internal battery. As the battery is such a tight fit he found that a solder point was touching the body of the battery and he had to insulate the battery from it. A couple of weeks ago I pulled the hand controller apart and put 3 layers of masking tape over the battery as I did remember not getting the new battery as snug as the old one. As there was some very strange behaviour with the mount I determined it must be the hand controller. I opened it up once more and removed the masking tape. When I held it up to the light, there was a tiny pin hole in it. I had kept the old battery and compared them and found that the positive "bubble" on the new one was about one millimetre bigger than the old one and hence this was stopping the battery from sitting flat within the circuit board. I removed the battery and filed the circuit board to accommodate the the extra millimetre and re-soldered it. I know the filing thing sounds dangerous but it really was necessary to fit the new battery and I was super careful. This has stopped the strange behaviour I was experiencing but the inaccurate slewing continued.
Stage 2 was to remove the motors as the scope was still stopping well short of the targets and the further the slew the worse it got. What I found was that the declination motor gear had 25 teeth and the drive gear had 50 teeth but the right ascention motor gear had 50 teeth and its drive gear had 100 teeth. Although the ratio is consistent at 2:1 I am sure this cannot be correct. My manual tells me +36x144 for each motor which is a 4:1 ratio. Obviously at 2:1 the scope will travel twice as far for each slew.
Am I right?

[g__day]

David,

The battery placement and resolution news is good to hear - I didn't know the battery size was so critical, nor that this type of battery was variable in its dimensions.

The gearing sounds absolutely bizarre and could easily account for what you are experiencing. I think you need to check with others users of the same mount what numbers of teeth their gears have. Having to set your RA ratio to +72x144 would be do-able. But I would be trying to work out did the factory ship it this way or did a previous user do something strange!

If you find all other users have a different gear ratio to you - then you can either try and purchase the correct set of gears for RA or adjust the gearing ratio in the SS2K.

That takes the cake for the most unusual problem I have ever heard!

Matthew

[ilife13]

Thanks Matthew, perhaps I'm not that stupid after all. I was beginning to think I was going to be highly embarrassed over a silly "rookie" error.
I will try and find the previous owner and ask some questions regarding the gearing.

David

[ilife13]

Thank you to everybody who helped me with this and a very special thank you to Matthew who spent a lot of time and brain power on it.
I believe the problem is now resolved. The battery was only part of the problem with a pin point short to the battery casing and the fact that the gears are non standard. Rather than the 36x144 ratio as indicated in the user manual it turns out my gear ratio is 36x288. I have only done some indoor daylight testing this morning but it looks very promising and the scope now slews to all parts of the sky and appears accurate. Fingers crossed for a clear night tonight. I will post on the real time testing as soon as it is complete.

David

[g__day]

David,

Glad its almost resolved. The SS2K does allow one to put their own gears into a mount - but this is the first time I've ever heard of one doing so - and a battery reset would mean you would need to know the non default gear ratios for everything to work.

Fingers crossed now - but it feels like you are heading out of the woods now!

Matt

[ilife13]

Matthew
All is good and back to normal. Accurate goto's just a little hiccup with PHD guiding but easily resolved. Clear night last night, I just have to remember how to operate it because it has been nearly 3 months.
David

[g__day]

David,

Well done - might be worth an article - how to fix things when they go totally beserk.

You did all the right things:

1. Ask for help and provide details
2. Eliminate all the sources of simple mistakes
3. Triple check everything
4. Get access to a greater experience base
5. Experiment continuously and post feedback to diagnosis what was and wasn't happening correctly
6. Lock into the correct problem and find the simple solution

Guarantee someone else in the next two to three years will have this exact same problem, and spend a fraction of the time solving it because of your efforts!

Great to hear its back to working well!

Matthew