Anybody used an Oscilloscope on the 3rd Gen?
 

I set out today to try to see the effect of the Twinpower and hooked up a Fluke 98 Scopemeter to try to get secondary ignition tracings with and without the Twinpower attached.

It did not go well. I was able to get the classic secondary ignition tracing on one leading plug with a very messy spark line, a very messy & garbled tracing on the other leading plug, and nothing sensible on the two trailings.

Anybody around here ever used oscilloscope on a rotary? What am I doing wrong?

i had a few pictures , from one on a fd with a two broken apex seals and the housings were made crap , thre really good to check apex seals and rotor housings

WTH are you talking about ? :rlaugh:

Beats me too. I think he posted to the wrong thread.

wow thats weird wrong post

I've been doing some testing of FC ignition components, and have snapped pics of a number of traces. I've been probing the ecu signal wires, and coil -ve terminal for most work, although I just added current measuring capability as well, which clearly shows the current limiting kick in after 1.6ms or so.

For more info, the test results are being posted here:

http://www.msefi.com/viewtopic.php?t=7544

Roger.

I think you need a current probe and a current probe amp hooked up to an o-scope. That is how I check the cathode current pulse train on high-powered transmitters. I personally don't trust the Fluke scopemeter...

There was not a lot to the hookup so I don't think that was the problem, a line to ground and an inductive clamp on the spark leads.

That did give me one proper looking secondary ignition tracing through the spark line just bounced all over the place. The Scope meter kept reading twice my actual RMP. I tried about every combination I could think of 1 cylinder through 8 cylinder, 2 cycle, 4 cycle. The trailing traces were just gibberish. No firing line to speak of no spark line to speak of, no kick at the end - zero, nada.

Is the Fluke known for this problem? Do you have to tell it anything special for a rotary? I have access to a Sun machine and I am going to try that next. I am also going to attach the clamp way down on the sparkplugs from under the car rather than closer to the coils than the plugs. Maybe I was picking up signal from adjacent wires?