Spektrum DSMR/DSMX Telemetry Brushless RPM Sensor SPMA9558 Miscellaneous Radio Accessories

I Used with E-Flite 40 & 60 A Pro speed Controllers and E-Flite 32 (14 pole) and 25 Motors. Added small ferrite cores on sensor leads to reduce/eliminate noise and false (high) RPM readings. Sensor Mfrs web site info minimal, but says that the sensor may work with only one of the two sense leads connected. Input circuit details would be helpful in determining any need/type of noise filtering to be added when false or erratic (high) readings occur. Verify readings with an external meter, such as an optical prop RPM meter, adjust reading at TX if needed.

I have several of these gadgets and they all work as advertised. Since there's no instructions included with the device, there's a problem that you need to know about. This gadget should work with any Electronic Speed Controller (ESC) but.......... without thorough testing I cannot be sure. I use mine on numerous 30 Amp and 40 Amp ESC's. I contacted the manufacturer (Eagle Tree) - not Horizon Hobby and was told how to properly connect the device to the receiver. Incidentally, this product is made by Eagle Tree and sold to Horizon Hobby (Spektrum). You only need to connect wire #1 to any ESC motor lead. It doesn't matter which one of the three wires you choose. Clip off wire #2 and wrap it around the RPM sensor. Program your Spektrum Transmitter so it recognizes the RPM readout in your telemetry data and you're good to go!