StormLauncher Charger -- can I use it for anything useful?

[Unterhausen]

http://www.rcgroups.com/forums/attachment.php?attachmentid=1643124
I have over 20 of these things, they have a PIC on there which is used to make a balancing charger. It looks like the programming connections are taken out to the edge of the board. I'm not a PIC expert, but it looks to me like I should be able to blink some lights with these or do something useful

Any comments?

[Unterhausen]

I see that the microcontroller (a pic16f716) is in-circuit serial programmable
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1999&ty=&dty=&section=&NextRow=&ssUserText=pic16f716

That looks like a pretty nice version of the pic, A/D could be useful

It has two tip125 transistors. I'm thinking the other sot8 chips are drivers for those. I haven't looked up the device on the heatsink yet.

[Unterhausen]

So I reverse engineered the charger a little more. Apparently they are regulating the high voltage with an LM317T, the two TIP125 are driven by LM358 Op Amps. Still looks like it might be a useful board.

Have to figure out how to program it.

[adamdb]

Please keep us posted. I recently bought 4 of these at Wal-Mart in the clearance aisle for $4 each. S/b easy enough to bring the 3 battery connection lines out to a normal header to have a 2-cell lipo charger, but if it could be repurposed for something else...? I could really use another 3 cell charger, I wonder how it measures voltage for the battery?

[Unterhausen]

the 16f716 has an A/D converter, so measuring the voltage should be easy. I think it has one shunt resistor, for measuring the current, not sure. I haven't traced the circuit at all, just ID'd the chips.

I was thinking about using it as a discharger. It might not be too hard to use it as a charger for 3s, the balancing might be a problem though.

[besligar]

I also have about 20 of these. When I converted the SL to a Strong Launcher I needed a way to charge the 3s while waiting for a my 610c to arrive and I used these chargers to do it.

What I did was brought the three connections (plus, minus, tap) out of the charger via extended wires. I left the original pins on the board so it could still be used for the original batteries. These three wires were attached to a three pin header. I used a red wire for positive, black for tap and yellow for minus for easy identification. The four pin connector on my battery had the connections as plus, tap, tap, minus. Plug the charge header into the battery connector using three of the four holes with plus to plus. After fully charged I shifted the header over one hole on the battery connector and let it charge again. The first charging charged and balanced 2 cells, the second charge charged and balanced one cell again with the remaining uncharged cell.

I realize it is not the proper way to charge and balance a 3s however the end result is a charged and balanced 3s. THe middle cell is being discharged and charged at around 4.2 v while the third cell is being charged. Works in a pinch and is the only use I have come up with so far for one of the 20 chargers lol.