Hitec sp6/10A controller

One of these has turned up in my collection.  I know it's an antique but I'd like to use it.  It has an adjustment screw but no obvious on/off switch.   
I have connected a 7.2v NIMH battery, a Graupner 600 motor and a Futaba R202GF receiver using the middle socket, and I've checked the fuse. Nothing happens.  So what am I doing wrong?

This hasn't got a BECC have you plugged a battery into the receiver I  bought one years back and I tried my corvette set up with it. No idea on reliability its a victim of miniaturization i suppose.

Yes - that was the problem but with a second battery powering the RX it now works fine.