Rear side showing wiring, a picture saves a
thousand words or whatever...
Speed Controller
To feed kerosene to the Solent a fuel pump is required. This is from a fuel injected car (Ford XR3 or similar) and 12v.
We needed to control the speed of this as this directly controls the Solent engines rpm / thrust. A friend that runs the local model shop (Nutty Norm) built this for me! It also works the normal sized pumps that model aircraft engines use like the Kavan one.
It has only two wires, and fits in series with the positive supply to the pump. The negative simply goes straight to the pump.
The components are as far as I can make out, a BIG metal heat sink, a small 100k potentiometer, two big power transistors that have 2N 3055H on them and a 'driver' transistor and he assured me that any driver type will do here. If you want to build this then I will draw out a circuit diagram for you just mail me UPDATE - NOV 99 - This type of controller causes surging.... back to the drawing board.. a voltage controller and not a current controller is required.
Rear side showing wiring, a picture saves a
thousand words or whatever...
Front showing the three transistors and single pot.