This synch probe can be used to synchronize your scope's display with a firing event.Most often, this event will be the firing of the number 1 cylinder. This is useful for parading secondary ignition because it allows you to determine which spark event corresponds with a specific cylinder. It can also be used to isolate specific portions of other types of signals such as the unique ID of crankshaft position sensor for instance. The probe works with both distributor (conventional) and EI (DIS) ignition systems.

The clamp connects to the input channel that your scope's trigger works off of. This is usually channel one or channel A.

Ignition System Connection

Simply clamp around the appropriate ignition wire. The clamp has two dots on one side of it's housing. The only consideration for connecting it is to be sure these dots are facing the spark plug.

Scope Setup

Setting up your scope for using the clamp is fairly simple:

· Begin by making sure your scope is set up to trigger off of the channel you have the clamp connected to.

· Connect your secondary probe or other test lead to the scope's other channel.

· On the channel you have connected the clamp to, select a volts per division setting of 2V to start. On scopes that adjust by setting the total voltage displayed, try to select a setting close to 20V.

· Set the time base according to the signal you will be looking at on the other channel.

· The clamp should produce a well-defined positive voltage spike. Set the scope's trigger roughly half way up the spike. On EI systems, set the trigger level as high on the spike as possible to avoid triggering on the waste spark event.

· Select a positive or rising trigger slope.

· Set the trigger mode to ”norm„.

The scope is now triggering off of the voltage spike produced by the clamp. This means that the scope is in effect, triggering off of the firing of a particular cylinder. This allows you to synchronize the display to recognize particular cylinders when parading ignition, isolate cylinders when superimposing ignition and isolate certain portions of a signal when looking at things like the unique ID of a crankshaft position sensor.

Fine-tuning

Adjust the time, voltage and trigger settings on your scope as necessary for the best performance on your application.