I bought a cheap (50 euro) Chinook helicopter beacuse it has 2 sets of counter rotating props. .

http://www.youtube.com/watch?v=1ds2xuYJuZY

I've taken it apart to see how it was driving the motors, thinkinh maybe that I could hook in a signal from an ardiuino. The battery outputs c. 8.5 volts and each motor draws 1.3 amps (only running one motor so maybe the battery mught limit current)

The circuit board is very odd as it seem to have no rf type stuff and is surface mount except for a few caps and the large transistors.

There are what looks like two LM339m Voltage Comparators (one is not labeled) and one LM393.

http://www.datasheetcatalog.com/datasheets_pdf/L/M/3/3/LM339M.shtml
http://www.national.com/mpf/LM/LM393.html


The transistors are labeled 04n03la which looks like it is http://www.datasheetcatalog.org/datasheet/infineon/1-IPD04N03LA_Rev...

Any ideas how this could be hacked into? I'd like to drive it from an arduino or similar.

The motors drive the counterrotating blades quite well with what feels like significant lift. An alternative is obviously som sort of motor driver, but i would be keen to see how these guys are doing such a cheap solution. I havn't looked into the transmitter yet

Cheers

Diarmuid