need some real time help with coil/dizzy starting issue (3 Viewers)

[g-man]

OK Spike, I see this from Jim C. I'll try to test it today. Also pull the dizzy cap and make sure it spins and the signal generator isnt loose.

Ow, my head.
I only tried a 81-87 dissy just now. If the DVOM was set to ohms and beep, as long as the dissy wasn't moving it showed 160ohm and no beepy. If the rotor tip moved by the stator, then there was a beep, and a flicker on the readout. If DVOM was switched to low voltage AC, and the dissy spun at 400RPM, then it showed 600mV AC. On DC it showed just a tiny flicker, a few random mV, plus or minus. This thing is a tiny magneto, but the discharge spike is only a volt, instead of 10KV.

 

[g-man]

View attachment 3141403View attachment 3141404

Is the "power transistor" inside the igniter? step 4 above is testing the " power transistor ON" Can anyone explain to me exactly how the igniter works and what is the power transistor?

 

[g-man]

spun the motor with DVOM on the dizzy signal generator plug ...got a steady beep but probably because the contacts are coming so quickly. But the ohm reading was around 160 ohms. and did fluctuate rapidly.

 

[OSS]

I can’t explain exactly how the igniter works, but this is how I “think” the electronic ignition works in a general sort of way:

The signal generator inside the distributor is basically a spinning shaft with magnetic blades on it. As each magnetic blade passes ever so close (but not actually touching) the magnetic pickup, that very faint magnetic pulse as a blade passes near is detected by the sensor which then transmits a very faint signal pulse to the igniter. Its known as a Hall Effect sensor.

Why to an igniter and not just the coil?
The signal pulse coming from the signal generator is extremely faint, so faint that no coil can boost it up to the necessary 40,000 volts to send out to the spark plugs.

So the igniter is there to act as a voltage pre-booster to the coil to supply it with a signal that the coil can use. Sort of like a preamplifier in a stereo.

Igniters are all solid state, so its the transistors inside it that boost up the signal. If one of those transistors burns up, no more ignition.