[TRADED/FOUND] Wanted EQ3 Dual Motor Controller/Set (or Advice/Help Needed)

[GC - South Aus]

G'day All,

Not having much luck lately!

Looks like I have bought a dud!

I recently bought a light weight mount (EQ3 - Dual Motors) so that I could get back into astronomy/imaging (well EAA) with a 50ED finderscope (wide field), with my youngest son. Just wanted something that I could get in and out of the house at short notice, and not be a problem setting up and exhausting my limited time with him.

Unfortunately I have bought a system that does not work. Not sure if its the controller chip or the motors. I can hear the motor click or engage when switching between North and South, but there is no motor movement at any speed or with any button press. The controller lights up green on the LED as it should.

I have used a 6V 1A Positive Tip PSU, a 6V battery, as well as just gone out and bought another 6V Positive Tip PSU with greater amps at 2.2A from JayCar (good money, after bad!). None of these power supplies seem to make the controller or motors work.

I think it's probably the controller chip in the handset/controller! Anybody got any ideas, thoughts or experience on this?

So, long story short! I am looking for anyone who has a spare controller or dual motor set available. Hopefully not too expensive, as I think I have almost spent beyond (including fuel, travel and new PSU) what the complete package is worth second hand!

Or has anybody got any other ideas on how I can either fix (i.e. is replacing the controller chip worth it or possible), or perhaps drive the mount motors (i.e. Arduino control setup)?

The mount also doesn't have the slow motion controllers (manual control cables), so I can't even control it by hand. At this stage I would also settle for a set of them!

Any assistance would be greatly appreciated.

I have attached an image of what the system looks like.

Cheers

Gav

(Note: Let me be clear here, seller was good and offered money back. However, I just want to get this thing working. It's just one of those things!)

[iborg (Philip)]

Hi


I've just been looking on the web to see if I can find some more information about this unit, and I can't find much that may help.


So a couple of questions for you, and with the answers, I might have some suggestions. My apologies if my questions sound like idiot ones, but, I have no idea what level of knowledge you may have about electronics. I am not wishing to insult or offend.



Do have and understand how to use a multimeter?


Do you know if the motors are simple DC motors or stepper motors?



If you don't know, can you tell how many wires are going directly into each motor? (I'm guessing two for a DC motor or four for a stepper motor)


You are using a tip positive power supply. Are you certain that is the correct way around?


Do you have the battery part of the system? I think this is shown in you photograph.


Philip

[bojan]

It may be this one:
https://forum.arduino.cc/t/dual-axis...scope/612962/3


I think Alex may have one such controller with burnt processor... so maybe your processor and his PCB...

https://www.iceinspace.com.au/forum/...ighlight=LXD75

[GC - South Aus]

Originally Posted by iborg

Hi


I've just been looking on the web to see if I can find some more information about this unit, and I can't find much that may help.


So a couple of questions for you, and with the answers, I might have some suggestions. My apologies if my questions sound like idiot ones, but, I have no idea what level of knowledge you may have about electronics. I am not wishing to insult or offend.



Do have and understand how to use a multimeter?


Do you know if the motors are simple DC motors or stepper motors?



If you don't know, can you tell how many wires are going directly into each motor? (I'm guessing two for a DC motor or four for a stepper motor)


You are using a tip positive power supply. Are you certain that is the correct way around?


Do you have the battery part of the system? I think this is shown in you photograph.


Philip

G'day Philip,

Thanks for your response, no offence taken.

I haven't used a multimeter since I undertook electronics in high school some 30 years ago nearly. Although, I think I could probably have a crack. But, this is something I would need to purchase as I don't have one lying around. I have read some similar experiences by others, who state that there is usually a significant drop in voltage out of the processor (around 3.6V instead of 6V) towards the motor, which is usually a tell tale sign that the processor is dead/not working correctly (according to others).

With regards to the motors, this is something I am keen to understand myself and I am not sure. I think they are stepper motors, if so I am hoping this will mean that they can be controlled via other means (i.e. OneStep). If not, it will mean buying either a new complete dual motor set, or NEMA stepper motors for the use of a DIY controller (such as OneStep or AstroEQ). Either way I am guessing significantly more money!

There is 4 wires in the RJ 11 cable and 4 pins on the RJ 11 jacks of the motor PCB's.

Yes, using positive tip.

No, don't have the manufacturer issued battery back as pictured.

Manufacturer instructions/guide: https://inter-static.skywatcher.com/...1316546609.pdf

Cheers

Gav

[GC - South Aus]

Originally Posted by bojan

It may be this one:
https://forum.arduino.cc/t/dual-axis...scope/612962/3


I think Alex may have one such controller with burnt processor... so maybe your processor and his PCB...

https://www.iceinspace.com.au/forum/...ighlight=LXD75

Hi Bojan,

Thanks for the links, I will have a read

Cheers

Gav

[iborg (Philip)]

Hi Gav


Based on the number of wires, and Bojun's links, pretty sure it is a stepper motor. Again, based on Bojun's links, replacing the controller with an Arduino may well be the best bet.


I had one set up to run a stepper motor, I'll see if I still have it around here somewhere. If I do, I don't mind posting to you to test the motors you have. At least we should be able to see if they are working.


If I do still have it, I'll get you to send me a better photo of the motor connector. Hopefully, I can set up something that will be easy for you to test.


Philip


PS I am pretty sure Bojun know more than I do about these things.

[sfarndell (Scott)]

If you're looking for a cheap, no frills arduino replacement, then the OnStep platform can do it. As it's modular you can build on it. I've made a few of these for my scopes and they are excellent.

For the cheap n cheerful (but still VERY functional) you could go with the WeMos R32 build https://onstep.groups.io/g/main/wiki/19670

Basic build is around $36 including the WiFi module (you'll need that) which can be controlled via your phone.

You can also add on a GPS module ($10) and build a wireless hand controller (which will be around $50) to make it a portable, stand alone mount. With the CNC shield, there is little soldering and fiddling about.

There are other options to really deck things out with automatic dew heater controllers, focus motors, etc, which will require more study and $$, but sill very inexpensive.

[PhilTas (Phil)]

Hi Gav,
Phil from Darwin here.

Just looking at the photos with your first post.
Photo 1 is the complete dual axis drive kit. This is the photo you see in the adverts for this kit.
Is photo 2 your controller? If so, what is the extra wiring?
The yellow and black wires, and the grey ribbon cable, are not standard.
Are these wires connected to anything else?

I have the dual axis drives on my EQ3-2, and my controller does not have this extra wiring.

For the purposes of testing, have you tried disconnecting one of the motors?
Unplug both RJ connectors from the controller, then plug one of them back in and test with the buttons. If it works, then plug that same RJ into the other output.
Repeat the test with the other RJ connector.
If one motor works and the other one doesn't, then the faulty motor might be loading down the controller to the point where neither motor works.

If neither motor is working then this points back to the controller being at fault.

I have two controllers. PM me and we can discuss sending one to you for test.

Cheers Phil

[GC - South Aus]

G'day everyone, thanks for your replies.

I am presently away from home again for the next 3 weeks, with limited internet access.

I appreciate everyone's assistance!

Philip, thanks for your advice and offer. I actually have a a coupe of Arduino Mega's and Nano's lying around. So might look again online to see if there are any examples. If you have any links on what you did it would be greatly appreciated.

Scott, I actually have an OnStep system now. But, I only have one and plan on using the one I have with another project. Don't want to have to keep reprogramming it to use between mounts. However, a cheap $36 dollar build might be a good alternative. Thanks for the links.

PhilTas, I have already tried all the troubleshooting you have outlined, without success! But, thanks for your guidance anyway. In relation to your queries, that was just an image I saw on the internet. The grey cable hanging down is just for an added ST4 guiding port (DIY). So the close up image is exactly what I have, minus the extra ST4 (DIY) wiring (just standard HC).

Thanks all.

Regards

Gav

[bojan]

For OnStep, see here:
https://onstep.groups.io/g/main/wiki/3860
People there are very helpful...


Also here: https://www.iceinspace.com.au/forum/...t=LXD75&page=2

[GC - South Aus]

Originally Posted by bojan

For OnStep, see here:
https://onstep.groups.io/g/main/wiki/3860
People there are very helpful...


Also here: https://www.iceinspace.com.au/forum/...t=LXD75&page=2

Thanks Mate

[GC - South Aus]

G'day All,

Thanks yo everyone's support.

I have now resolved this matter, it was the HC (Controller) that was U/S (now replaced). The motors are in-tact.

Cheers

Gav