RPM Indicator only

[DISAR]

Does anybody know or used an RPM indicator to measure the brushless motor rpm? The eagle tree does it but anything else?

[Doby]

You can monitor it with a Spektrum Telemetry module.

[DISAR]

Thanks, but I am looking for something cheaper. I have the eagle tree but it is not working any more and the standard repair charge is 30$ plus the repair cost plus shipping, it is better to buy a new one. But I actually want only the rpm.