Victor,
I have a question for you. If I put a 5 volt pulse from
a triple 4050 into the coil trigger pin and it is clamped
to 2.5 volts is that an FET or a bipolar transistor base
in there?

Still trying to get a handle on these RX8 coil failures
to be sure I understand it.

Paul Lamar


How are the failed coils different? Do they draw current or not? If you
ohmmeter the trigger lead are they different from good coils?
Victor

Hang on I'll stick one back in the test set up.

The first one I tried quit sparking but the voltage
going into the trigger was still limiting. I don't
have an ammeter on it as it is directly connected
to the moto battery.

Hooking it up to the 12 volt supply gave no current
going in and no spark but still limiting the trigger.
Ohmmeter 1500

Next failed coil.

Multiple triggering. Current draw about 5 to 6 avg. amps.
Same trigger limiting behavior. This coil would probably fire
but eventually over heat due to the high current drain.
Ohmmeter 1500

Next failed coil.

High avg. current drain 4 amps. Multiple triggering.
The interesting thing about this one is it continued
to self trigger after I removed the trigger signal.
Ohmmeter 1500

Next failed coil.

Totally dead but still limiting the trigger.
Ohmmeter 1200

Generally speaking the high current ones drag down
the supply to about 8 volts as it is not regulated.
I don't have a high current regulated supply.

That does not happen with the moto battery of course.

Paul Lamar