H_man

The bloody thing works now, Hurray ;D ;D ;D ;D ;D I changed the the Mosfet to an IRF830 (don't know if that helped). I just connected it up this morning after going over the circuit last night and it has come to life. The input pulses are 13V and output spike are >150V. I am now going to make a bigger inductor for bigger spikes :D Thanks to everyone for their suggestions, I found it reassuring to know that my circuit wasn't nonsense.

To clarify a few points.. The Mosfet used was a 2SK1358 which claims a drain-source voltage of 900V and a pulsed drain current of 27A. The power supply driving the pulsing circuit was also connect round to the inductor. I had an oscilloscope connected across V+ and Gnd, I assume the resistance of the oscilloscope is in the Mohm range so wasn't worried about losing my pulses that way as audioguru mentioned in his last post. Would a capacitor somehow be of help?

Thanks Audioguru. So I am now wondering if trying to produce spikes (for micro-seconds of high current and voltages) with this sort of circuit setup is a complete dead-end?

Hi, I built the circuit shown below (sorry, I don't have a drawing package to hand). I was hoping to get voltage spikes from the inductor when I had a high duty cycle for the pulses. Unfortunately I just got the inverse of the pulses (which wasn't so surprising), but I thought I'd get more of a kick from the inductor given the fast rise and fall times of the pulses! Details: Power Supply was giving 15V, Inductor was 0.1mH, Pulses were at under 10Hz and also 15V peak to peak. I had an oscilloscope attached where I have written +V and Gnd. |------------- Inductor---------------____________ +V | | | | | | Power Pulsing _|'''|_|""|_------Mosfet Supply Unit | | | | | |________________________________ |____________ Gnd Thanks