If the mosfet is properly connected to a load, then the MOSFET should be discharging at 70Hz. Put your oscilloscope probes across the load and measure the frequency of on/off cycles.I am using a 555 timer set at 70Hz, pin 3, to the gate of a p-MOSFET. I am using the same 12VDC supply for both the 555 and to source the MOSFET. Is there a way to physically determine what the frequency is discharging the source pin on the MOSFET ?