General Electronics question

[metalbender]

I need to measure a quick voltage spike from a motorcycle ignition. It is between 80 and 100 volts, low energy. For my multimeter to read it, can I connect a capacitor to capture the voltage then read it with my meter? If so, what would the specs be on the capacitor?
I also have an old Tek 422 oscilliscope but the problem is measuring a brief voltage spike.
Thank you.

 

[pauloynski]

The cap will not work since it will smooth out the spike. To see such a signal using an analog oscilloscope you need to make it repetitive (don´t forget to use the 10:1 input).

 

[haff99]

Most oscilliscopes have a single sequence trigger function that you should be able to use to see your spike. I don't know if your particular scope has it or not, but even the most basic newer scopes have this function today. It is critical for finding things like voltage spikes that are not repetitive. You just set the trigger voltage to be a certain voltage and when the scope detects a voltage above the trigger voltage you will see the spike.