DMC01 TReX v1.2 not talking to RC receiver Futaba R153F FM

Hi Geeks!

I have a brand new TReX DMC01 and trying to use it in RC mode.
TReX firmware is version 1.2
RC hobby transmitter - Futaba FM 40MHz TX 3 channel
RC hobby receiver - Futaba R153F FM 40MHz RX 3 channel

TReX jumper settings:
channel mix - NO MIX
battery elimination circuit - NO BEC
mode select - RC

I connect to DMC01 the two RC channels #1 and #2 from my FM hobby RC receiver Futaba R153F. I use standard cables. The DMC01 does not recognize RC signal on any of the channels. I tried to run normally and also tried Learning Mode… No success.

When I check RC signals using serial cable and TReX Configurator, it reads value 0xFFFF (i guess it’s out of range) on all channels while Futaba receiver is powered and connected on channels 1 and 2.
I provide screen-shot showing this.

Hobby servos (Futaba and non-Futaba) are talking to this FM receiver with no issues. The receiver is known to work. Are there any settings I can change in TReX Configurator to make DMC01 recognize the signal from Futaba R153F?

Lastly when I connect my other receiver Kyosho AM 27MHz, DMC01 works as expected. So that it is not broken or faulty.

Problem is, my AM receiver is 2 channel and I need to have 3 channels on my project. Was going to use 3ch Futaba R153F FM receiver for that purpose.

I attach the screen-shot separately.
Any help and advice appreciated.


see image attached


The thing that has me most worried is that everything is working fine with your other receiver. Just to make sure you’re not accidentally changing something while swapping receivers, can you connect them both at the same time? If you only have a few cables, you can just connect to one channel from each receiver and swap around which receiver is channel is connected to which TReX channel, and verify that only the signals from the 3-channel receiver aren’t getting read.

Do you have access to an oscillscope to look at the signals?

- Jan

Unfortunately don’t have oscilloscope at home :frowning:

I tried connecting the two receivers simultaneously using TReX to power them both (jumper set to BEC).
First I connect Futaba FM to channel 1 and AM receiver to channel 3.
And then vice versa leaving all cables in place and swaping only the receivers.

Still can’t get signal reading from Futaba R153F FM.
Can that be a compatibility issue?
Or is that a weak signal/receiver manufacture quality?

I think I’ll have to get another receiver as a workaround.


I doubt that it’s a problem with the quality of the receiver. There are just some characteristics we look for in the RC signals to decide whether or not there is a valid signal there, and apparently, something about the signal makes the TReX decide it’s a bad signal. It could be that the voltage of the pulses is too low to trigger the TReX input, or that the pulse rate is too low or too high; it’s difficult to tell without looking at the signal.

What is the rest of your system (e.g. what is your transmitter model), and where are you? I think the 40MHz is not typical in the US (at least a quick search leads me only to 27Mhz and 75MHz versions).

- Jan