Wanted: a replacement for an Astro Electronic FS-2 mount controller.

[Xilman]

My mount is controlled by an Astro Electronic FS2 unit. The FS2 pretends to be a  basic Meade LX200 and does so very well. Full details are at http://www.astro-electronic.de/fs2.htm

Unfortunately they have not been on sale in the EU since 2014 because of RoHS regulations. There may be a loophole there, in that the UK is no longer in the EU and so that may be a Brexit benefit. I will try to find out.

However, if anyone knows of a similar controller on the market, please let me know!  A web search hasn't turned up anything yet but it seems unlikely that nothing is available.

 

Thanks,

Paul

[Oddsocks]

Hi Paul

Was looking for an alternative to the FS-2 myself a few years ago for use with a Gemini G41 mount.

Have a look at the Ursa-Minor MC3 MKII:

https://www.365astronomy.com/MC3-Mk-II-Motor-Controller-for-Telescope-Mounts?search=ursa

No personal experience of these MC3's though, at that time I bought a replacement Pulsar II controller for the Gemini as it was easier to stick with a system I knew.

Alternatively, maybe OnStep? although you would need to build that yourself:

https://onstep.groups.io/g/main/wiki/3860

Regarding RoHS rules, with very few exceptions, the same rules that allegedly prohibited the selling of the FS-2 in the UK/EU still apply to the UK after we left the EU.

https://www.gov.uk/guidance/rohs-compliance-and-guidance#full-publication-update-history

I had the impression at the time that the FS-2 was removed from sale in the EU that the issue was more to do with the legally demanding admin side and open-ended EOL manufacturer disposal liabilities rather than the materials and components used in construction, which could have easily been switched to RoHS compliant.

HTH

William.

[JeremyS]

51 minutes ago, Oddsocks said:

Hi Paul

Was looking for an alternative to the FS-2 myself a few years ago for use with a Gemini G41 mount.

Have a look at the Ursa-Minor MC3 MKII:

https://www.365astronomy.com/MC3-Mk-II-Motor-Controller-for-Telescope-Mounts?search=ursa

No personal experience of these MC3's though, at that time I bought a replacement Pulsar II controller for the Gemini as it was easier to stick with a system I knew.

Alternatively, maybe OnStep? although you would need to build that yourself:

https://onstep.groups.io/g/main/wiki/3860

Regarding RoHS rules, with very few exceptions, the same rules that allegedly prohibited the selling of the FS-2 in the UK/EU still apply to the UK after we left the EU.

https://www.gov.uk/guidance/rohs-compliance-and-guidance#full-publication-update-history

I had the impression at the time that the FS-2 was removed from sale in the EU that the issue was more to do with the legally demanding admin side and open-ended EOL manufacturer disposal liabilities rather than the materials and components used in construction, which could have easily been switched to RoHS compliant.

HTH

William.

Interesting info William. I too have a Gemini G41 mount and Boxdörfer DynoStar controller (same supplier as FS2). Although it works fine, I sometimes wonder what I’d do if the controller became u/s. Were you able to establish if the Ursa Minor would work with the G41? I wonder if it uses the same protocols as the G42 which I note can be pre-programmed into the Ursa Minor.

 

[JeremyS]

Paul - might be worth contacting Alan Buckman at AWR Technology 

[AstroKeith]

Is your old one broken? 

[Oddsocks]

1 hour ago, JeremyS said:

Were you able to establish if the Ursa Minor would work with the G41? I wonder if it uses the same protocols as the G42 which I note can be pre-programmed into the Ursa Minor.

 

Hi Jeremy.

At that time I was told that the Ursa Minor “should” work ok with the G41, although you had to set the gear ratios and motor currents in the config setup yourself rather than the pre-programmed values, from memory the gear ratios are different between the G41 and G42 and I think the motors were larger in the G42 also.

Unfortunately since the passing of András Dán the Gemini website has become defunct and the manuals and specification docs for the original G41 and Pulsar I controller are no longer available to download for comparison with the G42/Pulsar II.

As far as the mount protocols go the G41 and G42 are just dumb mounts with no controllers or advanced features so you could use a third party controller using Meade protocols and control it as if it were a LX/Autostar mount or use a controller based on EQASCOM that uses the Synta/Synscan protocols.

When I replaced my failed Pulsar 1 controller with a Pulsar II one of the deciding factors over the FS-2 and Boxdörfer DynoStar controllers was the lack of Gemini G41 specific PPEC support, which I recall Ian King saying at the time that it really didn’t matter that much, but I was used to that feature helping with reduced guiding demands and bought a Pulsar II (which was about double the cost of the FS-2!).

William.

[Xilman]

Just heard back: the FS2 is on sale for UK delivery.

[Xilman]

7 hours ago, Oddsocks said:

Hi Paul

Was looking for an alternative to the FS-2 myself a few years ago for use with a Gemini G41 mount.

Have a look at the Ursa-Minor MC3 MKII:

https://www.365astronomy.com/MC3-Mk-II-Motor-Controller-for-Telescope-Mounts?search=ursa

No personal experience of these MC3's though, at that time I bought a replacement Pulsar II controller for the Gemini as it was easier to stick with a system I knew.

Alternatively, maybe OnStep? although you would need to build that yourself:

https://onstep.groups.io/g/main/wiki/3860

Regarding RoHS rules, with very few exceptions, the same rules that allegedly prohibited the selling of the FS-2 in the UK/EU still apply to the UK after we left the EU.

https://www.gov.uk/guidance/rohs-compliance-and-guidance#full-publication-update-history

I had the impression at the time that the FS-2 was removed from sale in the EU that the issue was more to do with the legally demanding admin side and open-ended EOL manufacturer disposal liabilities rather than the materials and components used in construction, which could have easily been switched to RoHS compliant.

HTH

William.

 

Thanks for the information about the UMi MC3 MKII. That one is new to me and I will investigate further.

The OnStep was found through a web search and it looks very promising.  It is possible to buy fully assembled kits from Instein, as here https://instein.eu/index.php?route=product/product&path=25&product_id=72

[Xilman]

5 hours ago, AstroKeith said:

Is your old one broken? 

Hard to tell.  It was old when I bought the observatory and contents. I have never managed to get the autoguider working very well but the mount is so good at sidereal tracking that much of the time autoguiding is not necessary.

The real problem is that the serial comms to the FS2 is becoming very erratic. Since returning to LP a few days ago  The Sky will connect satisfactorily for 30-60 minutes, then errors start appearing and eventually it won't connect at all. This behavior is very reminiscent of overheating but the ambient temperature, though warm (it is summer after all), is nowhere near as hot as it has been in the past when things worked just fine.

 

[Froeng]

27 minutes ago, Xilman said:

Just heard back: the FS2 is on sale for UK delivery.

Good find! You may also be able to source a new Boxdörfer MTS3+ then, as the the reasons Mr Boxdörfer stopped selling to the EU were similar…

[Oddsocks]

Hi Paul.

Before rushing off to replace the mount controller at least test the RS232 serial interface using the loop-back test because you don't know which end of the RS232 link is drifting, it could be the mount controller but it could equally be the computer's RS232 card or USB-RS232 adaptor, if that is what you use.

Next time you are at the observatory run the mount until comms is lost, disconnect the mount in the computer astro app and leave the computer running, unplug the RS232 DB9 plug at the computer end first and then disconnect the DB9 plug at the mount controller end of the serial cable and use a piece of stripped wire or a small, straightened, paper-clip to connect (bridge) female pins 2 and 3 at the DB9 plug of the disconnected RS232 serial cable at the mount end, then re-connect the RS232 cable at the computer end only and fire up a terminal emulator app such as HyperTerminal or PuTTY, connect to the same port number in the terminal app that the mount was using and run the loop-back test.

If the loop back test is successful then you can assume the RS232 interface chip in the mount controller has become weakened through ageing and the RS232 interface chip in the computer's RS232 card, or the USB-RS232 adaptor is ok.

If the loop-back test fails then you can assume that the problem lies with the computer's RS232 interface card or USB-RS232 adaptor.

You will need to download a copy of a terminal app such as PuTTY or HyperTerminal in advance and have the wire loop ready to bridge pins 2 and 3 of the DB9 plug at the mount controller end so that you run the test before the RS232 interface components have a chance to recover after disconnecting from the mount.

You can find a copy of PuTTY at putty.org:

https://www.putty.org

When you have a telnet session opened in PuTTY and connected to the serial com port with the bridged pins 2-3 of the DB9 RS232 serial plug then anything you type on the keyboard will appear in the message window and the loop-back test has passed (the letters you type leave the computer on the RS232 DB9 plug TX pin, loop-back via the bridge you made between pins 2 and 3 on the disconnected plug and arrive back in the computer on the RX pin and are displayed on-screen in the Telnet app), signifying that the computer end of the RS232 link is ok, if nothing appears as you type then the loop-back test has failed and the problem is more likely at the computer end of the serial link.

You will find plenty of YouTube videos and web documents explaining how to carry out this basic level of fault diagnosis on RS232 serial comms.

HTH

William.

[Xilman]

I hate Heisenbugs.

This afternoon, in the full heat of the day, I started by running the loopback test. Both the cable and and the USB serial port passed with flying colours. Incidentally I already had Putty and psftp installed, the latter being the method by which I transfer images off the TCS.

I then fired up MaximDL and connected to the telescope, successfully. They were both chatting away without error several hours later, during which other hardware debugging was taking place so a few reboots were necessary. The link always came up perfectly first time.

No idea what went right, except that running the loopback test may have dislodged some crud in the connectors.

With a bit of luck some astronomy may get done tonight, though a little light cloud is beginning to build up.

 

[Xilman]

A Heisenbug indeed.

 

The issue re-occurred after a few more hours up-time.  I had moved the FS2 to a possibly better cooled location.  The loopback test still succeeded after the comms to the FS2 became unreliable. Beginning to look very much like a FS2 p`roblem.

 

Anotehr test is to plug in a RPi with EKOS running and see if that sees the same behaviour after the Win box has failed to communicate. That test will have to wait until later.

[Xilman]

Now sure the FS2 is overheating.  The case became rather hot after around 3 hours use but at least I took some useful data on three variables before giving up at 23:15 UTC.

The sky was rather hazy and very moonlit, so I was quite pleased to get down to V=16 or so with adequate SNR. The air temperature was still 25C at close of play, which was close to 10pm local solar time as La Palma is about 75 minutes behind Greenwich.

Getting very close to buying a On Step box, which is made in Spain and should be quick and easy to ship. Already asked sundry questions about how much work will have to be done to convert cables, etc, to that system from the FS2.

[fate187]

I am also using a FS2 on my Alt 5 ADN mount. And I am also interested to switch to One step box. I couldn't be bothered to built my own, so this ready to go box is appealing. If you have bought this unit and you have gathered experience I would look forward to your experience :).

A hand controller would be nice though.

[Xilman]

15 minutes ago, fate187 said:

I am also using a FS2 on my Alt 5 ADN mount. And I am also interested to switch to One step box. I couldn't be bothered to built my own, so this ready to go box is appealing. If you have bought this unit and you have gathered experience I would look forward to your experience :).

A hand controller would be nice though.

The raw controller is given as €220 and a hand controller as an additional €110 so the latter is presumably available.

I am still waiting for a reply to my inquiries. Perhaps a phone call may be more effective.

BTW, although the FS2 is not available in the EU, I am in the UK half the years and the UK is not in the EU. If you need a replacement ...

Edited August 2, 2023 by Xilman
s/perhas/perhaps/

[Xilman]

Just kludged together an old 12V, 4W, 100mm diameter cooling fan and a grotesquely over-specified cable and strapped it to the FS2 with cable ties. Both components were found in my junk heap and the cable, which can safely pass 50 amps or more, just happened to have the right connectors  at one end to attach to the FS2's PSU.

There is a pretty ferocious draught blowing over one of the two large surfaces on the FS2 now. Let's see if it helps enough.

I would prefer not to spend several hundred EUR/GBP/USD if I don't need to.

[fate187]

Thank you for the offer Xilman, but the FS2 is a little bit dated in terms of controlling mount and selecting target if you are using it for visual like me. There is no meridian flip and selecting targets or coordinates is tedious. Still, it works well, so I am in no need to hurry a change 😊. Just spoilt from Skywatcher and especially AP1100 mount control.

[Carbon Brush]

I don't know this equipment, but have a couple of possibly useful comments.

As a very general rule, if after some years, something starts to fail on heating, it is generally down to component degradation.
The fan is just delaying the failure.

If you have a USB/serial adapter in the line, they rarely provide full RS232 signal levels - +/-12V signalling.
Old RS232 interface circuits often expect a half decent signal level. more recent circuits are more tolerant.
Could it be down to marginal RS232 levels that drift on heating? A quick glance with an oscilloscope will help show what is going on.

On a different note. ROHS rules and regulations.
Components sold within the EU have been ROHS compliant for many years. The law became active in (I think) 2006.
However, component suppliers were getting things set up much earlier - pre 2000 I think. The grey cells are vague on dates from 20 years back.
We found that swapping to lead free solder had almost everything sorted because component suppliers had done their job.
I doubt ROHS non-compliance was really a reason to stop selling. Unless the manufacturer wanted to keep using his 1990s and earlier components stock.
I picked up a lot of non compliant components cheap in the early 2000s. For use in applications where ROHS was not yet a consideration.
The distributors were clearing their stock to avoid rik of mixing parts.

HTH, David.

[Xilman]

47 minutes ago, Carbon Brush said:

On a different note. ROHS rules and regulations.

Components sold within the EU have been ROHS compliant for many years. The law became active in (I think) 2006.

Thanks. I will run with the fan for a while to see whether it helps, though I realise that all things die eventually and need to be replaced. Not had a clear night since 31 July to check it out.

The RoHS issue is, I believe, nothing to do with the components used. As you say, all modern components are compliant. The issue is that the regulations required too much administrative work: setting up procedures for end-of-use return of items sold, paperwork to demonstrate compliance, and so on. The cost of that work outweighed the profit made on selling to the EU market.

[Annehouw]

My mount is controlled by an ageing FS2 and I have been thinking of the "what if it dies" question for a few years.

It turns out that I am not the only one. I found a group that is developing a successor to the FS2, based on the OnStep project designs.

You can find a discussion (in German) here: https://forum.astronomie.de/threads/teenastro-ein-onstep-projekt.259256/

More information in the user group, which has a Wiki: https://groups.io/g/TeenAstro/wiki/Home

The only catch is (and that is the reason I have not migrated yet) that it is a build project: All the electronics and software development has been done by the team, but you have to 1) have the PCB printed (using the design drawing that is provided) 2) order the electronics (there is a parts list) and 3) assemble the hardware.

According to the discussion group, total cost will be around €200,- but of course you will have to put in the effort to do the soldering.

 

 

 

Edited August 7, 2023 by Annehouw

[Xilman]

As noted above, it is possible to buy a ready-built unit for €220 from https://instein.eu and you may wish to go down that route.

If you wish to replace the FS2 with another, they can be shipped to UK, but not NL. I often travel between UK and ES ...

 

[Xilman]

Cloud stopped play after 4.5 hours of observing. During all that time not a single packet out of well over 50,000 was dropped between the CS and the FS2.

I am now convinced that the problem was overheating of the FS2 and the addition of the fan has fixed it. I accept that it may only be a temporary fix.