The grandfather of all waveforms is the secondary ignition waveform. Technicians have been looking at this waveform since the 1960s to determine the health of ignition system components. The secret to being able to capture and analyze secondary ignition waveforms is understanding what is happening in the coil and at the spark plug and how the scope measures and graphs the voltages and ignition event. Measuring the voltage of the secondary ignition directly is not an option, these high voltages will damage any scope or meter. To capture a secondary ignition waveform requires a capacitive probe. This type of probe can be either the traditional clamp over an ignition wire or a "paddle" that makes contact with the surface of the coil or wire. The primary and secondary windings of the coil transform the energy from low-voltage/ high-current energy to high-voltage/low current energy. Eventual this energy is discharged through the spark plug electrodes. The flow of energy changes the the magnetic field in the wires or coil. This change in the field is picked up in millivolts by the clamp or paddle probe.
展开▼
