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[Phill]

I have finally finished building my replacement AstroEQ based on Tom's board. Tested it today and the RA works fine but the DEC motor just rocks, moves a bit, buzzes or stops.

I've swopped motors and drive boards and it's definitely something wrong on the main board or the ATMEGA162. I've resoldered joints and generally cleaned everything up but I cannot get it fixed, which leads me to think it might be a faulty IC. I've removed and replaced it in the socket to no effect.

I'll order a replacement 162 but in the meantime I wondered if anyone had experienced this before or had suggestions on how to track down the fault.

Kind regards

Phill

[TCWORLD]

Hi Phill,

Sorry for the delay in responding. I'm very snowed under at the moment at work.

Could you post a couple of pictures of the soldered board (top/bottom) - I can have a look and see if there is anything I can spot that might be causing the issue.

If the motor is not properly moving in the way you describe, the issue is unlikely to be with the ATMega. It's more likely to be a bad connection between the motor driver and the motors - if one wire of the four is not well connected, the motor will typically just bounce around and make lots of unpleasant sounds.

You could check whether one of the contacts within the sockets for the motor driver is damaged, or if there is an issue with the RJ11 connector (e.g. bent/broken pin).


Kind Regards,
Tom.

[Phill]

Hi Tom, thanks for the reply and no don't worry about the time. I hope work eases off for you.

I'll sort some photos out when I get the chance. The reason I considered it might be a problem on the 162 is the following.

Good connectivity between the 162 socket pins and the motor driver socket pins.
Fault does not follow motor or driver. Both motors work on RA and both drivers work on RA.

I've removed the 162 and cleaned the pins to no effect.

As it happens I'm not impressed with the RJ11 sockets or cables so I'm tempted to hard wire.

I'll get back to you with photos asap.

Kind regards

Phill

[Phill]

Hi Tom,

I removed the RJ11 sockets and hard wired the steppers using 4 individual wires rather than the rather poor lightweight telephone cable I had.

All works fine.

Thanks.