EQ6-R Pro controller board

[IDM]

My EQ6 R Pro mount died last night and on pulling the controller board out I found that Q3 had fried (See photo). I don't suppose anybody has a high resolution photo of the board or indeed has a board visible so they could tell me the part number? Unfortunately my Q3 is so damaged I cannot read it properly. I think I can see X4RV but not sure about the 4. All very frustrating.

Cheers

Ian

[bosun21]

@malc-c has spare boards that he repaired which he is selling at very reasonable prices.

[IDM]

1 hour ago, bosun21 said:

@malc-c has spare boards that he repaired which he is selling at very reasonable prices.

I have been in contact with him already and his boards unfortunately don't fit the EQ6r pro mount. But thanks for the idea.

Ian 

[malc-c]

Yes Ian and I have been conversing via PMs.   There are two components that have obvious damage, one being a MOSFET and readily available, but we have been unable to identify the part Q3.  I know there have been other posts relating to an identical device but have not been able to locate them.  As the mount is less than 2 year old I've advised Ian to contact the retailer and see if he can get a replacement under his consumer rights as on this occasion he didn't do anything obvious just as using the wrong cables.

If anyone can advise what Q3 is and recommend a readily available part (I have account with RS Components) then I will gladly take the board off Ian and try and effect a repair.  His mount being the EQ6-R the board shape is totally different and I only have a couple of EQ6 boards available.  I also lack the equipment to replace the ARM processors on these newer boards... at least for the time being, so if that has been damaged we are out of luck.

 

Edited December 15, 2023 by malc-c

[Ryachu]

Hi,

  Just had a look at the PCB in my EQ6-R Pro with the code MC015 Rev. E 2019.04 which looks very similar to yours. The component appears to  be marked 49T which https://www.s-manuals.com/smd/49 suggests is a 4.9V low dropout regulator. Unfortunately there was a blob of flux at the left hand end and scratching that off has now removed all markings !

 

[Ryachu]

Please ignore the above. I powered up the mount and had a quick sniff with a DVM. It doesn't look like a voltage regulator with 12V on the "OUT" pin and 0V on the "IN" pin. It seems to be marked A49T which suggests an N-channel MOSFET in an SOT23 package.

[malc-c]

Thanks for going to all that trouble to ID the Q3 component.  I'll check for component availability (or similar) later when I have a little more time, and drop Ian a PM with a view to attempting a repair

[IDM]

On 15/12/2023 at 11:09, malc-c said:

Yes Ian and I have been conversing via PMs.   There are two components that have obvious damage, one being a MOSFET and readily available, but we have been unable to identify the part Q3.  I know there have been other posts relating to an identical device but have not been able to locate them.  As the mount is less than 2 year old I've advised Ian to contact the retailer and see if he can get a replacement under his consumer rights as on this occasion he didn't do anything obvious just as using the wrong cables.

If anyone can advise what Q3 is and recommend a readily available part (I have account with RS Components) then I will gladly take the board off Ian and try and effect a repair.  His mount being the EQ6-R the board shape is totally different and I only have a couple of EQ6 boards available.  I also lack the equipment to replace the ARM processors on these newer boards... at least for the time being, so if that has been damaged we are out of luck.

 

As an update I exchanged a few calls with the retailer and they also contacted Skywatcher who stated that the warranty was out even though the mount was 3 days short of 2 years old. They offered to sell me a board at cost price and at the end of the day I didn't want an expensive doorstop, so a new board has just arrived.

I have just checked Q3 and it was initially covered in flux but with a bit of careful wiping with iso-propanol I can read the part number as A49T. Google seems to name it as A49T AO3404 which is a 5.8A N-channel MOSFET. I could not locate the part easily in the UK and most of the suppliers are in Asia. I have ordered a strip off Ebay. I know its not the best place to buy legit components, but I do have the capacity to test the transistors so will check them out before attempting the fix.

Many thanks to Mal-C for his help and support and to Ryachu for inspecting his board.

I will let you know how things progress.

Thanks,

Ian

[malc-c]

Ian,

Thanks for the update, and I wish you had pushed for your consumer rights to get a free replacement. Spending around £1400 on a mount you would expect the components to last a reasonable amount of time, especially if it had been used correctly.  However, if the board was offered at cost price, then that's better than nothing and a compromise that you were happy with.  The availability of the part in the UK doesn't surprise me.  I've not looked yet, but I'm betting that a alternative part could be found with specifications similar or very close.

It would be interesting to see how you get on with the repair.  Please take some pictures as you go and document the process on the "slightly blown motor board" thread here  (with cross ref to this original thread).  That will help anyone else who might have the same issues.  

[IDM]

5 hours ago, malc-c said:

It would be interesting to see how you get on with the repair.  Please take some pictures as you go and document the process on the "slightly blown motor board" thread here  (with cross ref to this original thread).  That will help anyone else who might have the same issues. 

Yes, I was planning on doing that. I had to order 50 transistors (they are cheap) so if the repair works, I am more than happy to help anybody out who has the same problem.

[IDM]

5 hours ago, malc-c said:

Thanks for the update, and I wish you had pushed for your consumer rights to get a free replacement. Spending around £1400 on a mount you would expect the components to last a reasonable amount of time, especially if it had been used correctly. 

I totally agree. The issue becomes that trying to force their hand further was going to take time even if successful and needed a working mount. However, next mount I buy must have a minimum of 2 years warranty. I see that Zwo provide 2 years with the AM5.

[malc-c]

To be honest a warranty is irrelevant.  A lot of retailers seem to think that after whatever warranty period has elapsed any issue that develops is down to the manufacture, or that its "tough luck".  This is incorrect.  The Consumer Credit act 2015 tumps any warranty.

The only issue here with things such as mounts is that just by nature of use there are lots of avenues for the retailer to point the finger at other possible caused and thus wash their hands of any responsibility.  There are retailers such as FLO and RVO who try their best to help, but equally there are those that try and wriggle out of it.  For example, when you by a £1400 EQ6-R it doesn't come with any "official" power supply.  It gives the basic requirements, but within that specification you can get things off e-bay for a couple of quid, to a dedicated regulated PSU costing upwards of £100.  - Same with EQDIR cables.  Most new mounts come with USB ports, but no USB cable is supplied.  So when a board goes pop out of warranty these are things that can be used as a way out of paying up.

As you say, often resolving these sort of issues is a lengthy process, and you can end up with a mount that can't be used until its resolved.  The risk is then to purchase a replacement part and then try and recover the costs, which as that was never sanctioned by the retailer could still leave you out of pocket.

[IDM]

As an update on this issue the strip of 50 transistors I ordered through Ebay arrived from China just before new year.

I removed the damaged Q3 using a soldering iron and watchmakers screw drive to lift the broken transistors. Once one side was done I let the board cool before doing the other side, thus removing the device. Excess solder was removed with the iron. I then cleaned the flux up by scrubbing the board with propan-2-ol and an old tooth brush. See image below.

The next part is the more difficult in that soldering surface mount devices is always a bit of a challenge (or at least it is for me). I took one transistor held it in place with fine tweezers and added heat from the soldering iron which I had loaded with fresh solder to just one of the three pins. I did this as quickly as possible to avoid excess heating of the transistor. I held the device until the solder had definitely set before repeating the process for the other two pins of the transistor. Once done I re-flowed the solder to pin1 to check all were reasonably soldered. See second photo.

Once complete I applied power to the board without connecting it to the mount. The red LED lit up so at least I was now getting power. I then attached a USB cable and was ASCOM could detect the board and see it as a parked mount. I finally put the board back in to the mount for final testing and all seems to be well. The mount un-parks and will slew to targets.

So in summary if you get a board that appears dead, then check Q3 as this was the only device that failed on my board. If you find Q3 appears damaged I have lots of them that I can provide if you want to attempt your own repair. Alternatively if you know someone who can do the work then I am again happy to supple them. Or if you are totally stuck I don't mind attempting the repair for you, at no cost other than the shipping of the board.

I hope someone finds this helpful.

Kind regards and happy New Year

Ian

[malc-c]

Great job Ian, and just goes to show that for a little patience and small outlay you have your mount up and running.  Not only saves shelling out £160 or more for a new board when a component costing a few pence was all that was required, it saves items like thins ending up in land fill.

Well done... see soldering isn't that difficult  

[Neil H]

Soldering isn't that difficult ? Well not for some , use to solder a lot when I was building large RC Helicopters but my hands shake now and I would solder everything else but not the part I need 😂

Edited January 2 by Neil H
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