View Full Version : E-Mag

Jim Talbot
09-14-2020, 04:23 PM
I have an 0-360 built by Mattituck in my RV-7
The engine has a Lightspeed Plasma II and a Slick impulse mag.
My AF-2500 gets the Tach signal from the Slick magneto.

The Slick is nearing 500 Hrs and I am planning to replace it with an E-Mag.
Can I use the Tach signal from the E-Mag connector #6?

New Zealand

Shawn McGinnis
09-15-2020, 10:39 AM
It should work if you use a 5V signal level. Otherwise you might need to modify the analog module to accept higher voltage pulses. You will also need to change the Pulses per revolution in the calibration.

Jim Talbot
09-17-2020, 03:13 PM
Thanks Shawn
The E-Mag installation manual says the tach output on connector #6 is two 10v pulses per revolution.
Connecting a diode (presumably a 5V zener) from the tach output to ground drops the voltage to 5V.
The AF-2500 RPM would be changed in calibration for four pulses per two revolutions.
If I connect the E-Mag tach output directly to the RPM input on the AF-2500 with the zener diode to "common" would this be OK?

Rob Hickman
09-17-2020, 04:21 PM
Wire it exactly like the PMAG manual, connect both ends of the diode to the PMAG.