Weekly Waveform #9 - Ignition Primary Current and Voltage

WARNING!! if your using a scope that has a maximum input voltage of 200volts of less you should use an attenuator to protect your scope.
We will be testing "dumb" ignition coils for this test because the newer smart coils do not give us access to the primary voltage control wire. In the video I will show you key points of the current and voltage waveform. uScope uses the 10:1 attenuator.
Connections for each channel
Channel 1 - ground connected to engine block or battery negative
signal wire connected to ignition primary control.(this is the normally the negative side of the coil)
Channel 2 - low amp clamp around either primary wire for the coil. Power wire or control wire will work fine.
Settings for each channel
Channel 1 - -20volts to 400volts with attenuator probe selected. If you don't have a custom probe with those settings you can select the factory option for -400v to 400v
Channel 2 - 10amps or 20 amps depending on the vehicle
Most scopes 20ms/div to 100ms/div depending on if its a single cylinder capture or all cylinder capture.
Snap-on will be 5ms to 10ms sweep time.

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60 amp PDI low amp clamp with banana plugs- https://amzn.to/3qznAW0
Cheaper hantek low amp clamp(I have never used this clamp) - https://amzn.to/2JwUC8x
20:1 attenuator - https://amzn.to/2JSicwl
10:1 attenuator for uscope - https://www.aeswave.com/Primary-Ignit...
back probing set - https://amzn.to/3587E46
secondary ignition pickup(we will need this shortly) - https://amzn.to/35bxlkm