Hi Guys,

I need to turn a motor in a clockwise as well as an anti-clockwise manner however lab-view can only output a positive voltage. Therefore i tried this circuit out with the motor connected to both the collector of the npn and pnp transistor. It still doesn't work. Please advise.

Many thanks.

 

whats wrong with an h-bridge?
why use a +/- power supply?

see here forexample..

 

If you have the negative supply available, that circuit should (almost) work. But running a motor off a 9V battery, if that's what powers it, will run down the battery very fast.

The circuit can't work because the diodes are facing the wrong way. And there ought to be pullup/pulldown resistors from the base to the emitter on both transistors. And are you really truly sure that the two transistors can never be on at the same time?