BradtheRad and Crutschow thank you both very much for your quick help!
Crutschow, that circuit worked perfectly in simulation and I will build it up tomorrow (components are all in the lab) and hopefully get it working!
Brad, thanks for the advice, I would really like to improve my knowledge of transistors, FETs etc. and how to implement them in a circuit. Could either of you suggest a good book/online course/anything that would be a good start? I have seen loads online, but there are so many it is hard to pick one!
Thanks again,
Andrew