GxT Ferret 92 Color Labscope - Manual (Page 10)

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Setup Example - Ignition Parade Pattern
This example uses the Ignition Scope mode found in the main
menu. The Lo Amps Probe is connected to the wire that supplies
battery voltage to the coil pack. The ignition adapter is connected
to Channel 1. The spark pickup is connected around #1 cylinder
spark plug wire.
Setup Characteristics:
Channel 1
Voltage ........................ DC Coupled, Ground in the Middle, 1.5V
Time Base ........................... Variable due to the trigger selection
Trigger ..........................................................RPM Mode, 2 Cycle
Lo Amps Auxiliary Channel
Amperage ...........DC Coupled, Ground at the Bottom, 10 Amps
When using the RPM trigger the scope does several things for
you. First of all, peak detect mode is turned on and is used on the cylinder that the RPM trigger is attached. Peak
detect makes sure you see the fi ring peak for that cylinder. The time base is being constantly altered so you only
see the proper number of cylinders on the screen. You can rev the engine up and down as fast as you want, but
the scope will only display 6 cylinders. In the example above a 6 cylinder car is being tested. You see 6 cylinders
and the beginning of #1 again at the very end of the screen. This is normal. You can use the Hold function and
activate the cursors to measure any part of the waveform.
Setup Example - Ignition Single Cylinder
The setup and leads used are the same as the Ignition Parade
Pattern. The only change is the choice of the trigger.
Setup Characteristics:
Channel 1
Voltage ........................ DC Coupled, Ground in the Middle, 1.5V
Time Base ..........................................................................25 mS
Trigger ........................................................................Cylinder #1
Lo Amps Auxiliary Channel
Amperage ...........DC Coupled, Ground at the Bottom, 20 Amps
You can move the number one pickup from cylinder to cylinder
to pick out individual cylinders for closer inspection.
Setup Example - Ignition and Fuel
In this example we are viewing the relationship between the fuel
injector pulse and the ignition system performance.
Setup Characteristics:
Channel 1
Voltage ........................ DC Coupled, Ground in the Middle, 1.5V
Time Base ........................... Variable due to the trigger selection
Trigger ..........................................................RPM Mode, 2 Cycle
Channel 2
Voltage .......................DC Coupled, Ground on the Bottom, 80V
Lo Amps Auxiliary Channel
Amperage ...........DC Coupled, Ground at the Bottom, 20 Amps
This is a great way to see the interaction between fuel injection
signals and ignition signals.