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 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!

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!

I bought 2 of these and am using them on an Eflite power 32 14 pole motor. I get erratic readings between 1400 and 5000 rpm. The readings jump from 10,000 to 120,000 rpm. The readings below 1400 and above 5000 are accurate. Both sensors perform exactly the same so it appears to be a design problem as oppose to a defective sensor.

I have 7 different aircraft from props to jets. Every one of my airplanes has one of these sensors in it. I keep buying them in hopes that Spektrun will finally get it the bugs out, so far they haven't. They aren't expensive and they are worth it for the novelity of it, It's just another "GADGET" which we all probably have plenty of already. To be honest some of the ones that i have do get reletivly close as long you have the correct pole setting. Try one you might get lucky!!

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As mentioned, I too have bought now three of these sensors hoping that one will read correctly. It's a cool feature to have but none of mine read the correct RPM. Still hoping I'll figure a way to get it to read right

I’ve had two of these and they do not work with a high voltage set up. (10C)… I purchased a Hobby Wing high voltage sensor from Heli Direct and it works fine. Need to mention this limitation with unit documentation.

I bought one of these for my electric H9 carbon cub and hooked it up just like the instructions say to. I kept getting faulty readings even though I know it was installed right and the pole count and ratio were set right in the telemetry settings. Sent it back, got another, and the same thing. So I finally thought I would try the SPMA9569 for the gas engine backplate installation for my E-flite power 60 electric motor. SPMA9569 Came in the mail, so I made a bracket from from one side of an engine mount and mounted the sensor right next to the set screw on the prop adapter shaft. The cowl won't fit if the sensor is side mounted so I mounted it on the underside of the motor. Perfect fit! Now I have perfect RPM readings confirmed by an handheld infrared rpm sensor. Nice to have an accurate sense of what speed my motor is running finally!