Hi,
I bought an MK129 for my daughter as her first soldering project. She’s completed the assembly (with a little help from me) and it’s only semi functioning. There are a few problems:
[ul]
[li]Whatever I set RV2 and RV3 to motor M2 will not activate[/li]
[li]Both LEDs activate but not consistently - although I think these are supposed to reflect the light levels on the sensor so this is probably expected?[/li]
[li]Motor M1 generally activates as expected but sometimes (usually after I turn it upside down to look at the connections) I have to bend the circuit board slightly in the middle to bring it back to life[/li]
[li]The circuit only functions in this limited way when the ‘straight’ mode is activated, the ‘wiggle’ mode kills it outright[/li][/ul]
I’ve done the following to try to resolve this:
[ul]
[li]Checked all the soldering joints[/li]
[li]There were a few connectors which looked a bit poor but I have re-done them myself[/li]
[li]Covering the light sensor stops M1 from running as expected[/li]
[li]Checked the non-functioning M2 motor by connecting it directly to the battery, it functions fine[/li]
[li]Checked both the capacitors are connected the right way around with a multimeter[/li]
[li]Checked the resistance of the sensors varies with light on them[/li][/ul]
Can you provide me any guidance on how to resolve these problems? I’m thinking that there’s a loose connection on the ‘right’ side of the circuit (as in the right side of the schematic) but I’m not really sure how to track it down other than by eye. However, I’m more concerned that I need to bend the circuit sometimes to get it to work, this doesn’t seem like a connection problem to me (at least no one that I’ve encountered before).
Any help much appreciated.