The RPM-1 for Experimental / LSA aircraft is a 2 1/4” sunlight readable color display instrument providing two universal RPM inputs that is primarily intended to measure engine and/or rotor RPM. The display can be configured to display single or dual RPM or it can be configured to display engine and rotor RPM as used in helicopters and gyroplanes.
The RPM-1 also has a maximum values display screen as well as a handy magneto check function. The RPM-1 includes a number of timers such as a Hobbs meter which can be set to the current engine time and is also password protected, an engine running and flight timer as well as a programmable maintenance timer to schedule routine engine maintenance.
The RPM-1 can also be interfaced via the CAN bus to an external RDAC unit (Remote Data Acquisition Unit). This allows for easier installation as the RDAC unit is normally mounted in the engine compartment.
Installation was straight-forward. I had to connect a resister for my Hall effect sensor. I find that a bit hokie. They should place the resistors internally and have them selectable for the various values cia the set-up menu. I wish the sweep gauge had some number on the circumphrance like you would have on an actual analog gauge. Overall I like it.
Indicator does not work off of the magneto switch lead as indicated in the instructions. The picture of the installation on the MGL web site is wrong. They show the P lead connected to the vent screw on the back of the mag, not the switch lead as intended. When I contacted MGL I was told that I needed the Hall Effect Sensor. The instructions for setting the number of pulses is misleading. I had to set the pulses 15 times higher than the calculated number to get a reasonable indication. It would be impossible to set this up without a hand held tach.