[sefiro]

Chiming in late.

You'll need a very expensive meter or oscilloscope to sample the blips.

Ie. Cranking at 180rpm is 3 rev per second,, that would be 6 NE blips per second. A recommended sample rate of 18-30/s would allow you to count/verify the blips. You could also use duty cycle measurement to see ratio of blip to nonblip

Without it, the meter is melding the data together assuming it is mmm easuring a continuous voltage.

For the G blip (every 2 revolutions), you might be able to use any old analog meter and watch the needle bounce.

Sent from my Pixel 5 using Tapatalk

 

[sefiro]

Congrats!

As a late follow-up to the sampling question.

• the smaller amplitude on the avom is related to a likely smaller pulse width due to the increased frequency. The AVOM needle is mounted to a coil that moves magnetically when current is supplied. The needle can't move mechanically fast enough to reflect the actual voltage before the current is removed.
• once the car is in idle or rpms up, the frequency will likely cause the avom needle to sit in the middle of not move at all.

A normal scope to display the wave.form still runs in the $Ks. But there are a couple of options

• Duty cycle/Freq DVM. You can typically get a quality one starting around $100. To use, you should know a little about the wave/signal you are measuring. (Is it rounded, square, consistent voltage etc). Fortunately we are dealing with simple square signal. On the Free setting, the DVM will tell you blips per second. The Duty Cycle will tell you % the blip is on. (Ie if a blip is on for .25 sec, the duty cycle is 25%)
• Intro scope. You could cobble together a scope using a Pico 2204a mso and a laptop. Pico makes a number of $Ks scopes, but the 2204a acts like a data longer that passes a digital signal to the software on the laptop. Assuming you have the laptop, you could get set up for around $150.

-

Sent from my Pixel 5 using Tapatalk