Continued from Part One. After the MOSFETs arrived! I attempted the rear MOSFET labeled U4 first. Instead of desoldering it, I just clipped the legs and heated up the other side. It come off without a hitch. Cleaned up the pads, added some flux and soldered the new part. Piece of cake, one more and I am done. Back side MOSFET before removal The second one didn’t go so well. There is a large diode above the MOSFET which makes it hard to heat up enough to remove it. Adding more heat was a bad idea as the MOSFET rear drain plate transfers heat rather well and heats up the PCB. Which, combined with me trying to pull the MOSFET out with tweezers, I ended up lifting …
Bluetooth Roomba Part One
A few weeks ago my dad called to let me know he had found a Roomba Discovery with the SCI (serial port) for $15. The first one I received that he found didn’t have the serial port so I gave it away. All that was missing was the remote, so he got it for $10. What a deal! Unlike the first one, the battery was not recoverable at all. So the weekend before last while visiting the Raspberry Pi tour at HackerDojo, I stopped by Fry’s Electronics to pick a new battery and a few components to add Bluetooth to the Roomba. Currently I am using Bluetooth since that is what I have on hand, later on I will probably convert it …