Alternatively to using the cable, you can also use a separate receiver.

Advantage of this method

  • No cable to the pilot's TX required
  • Antenna can be mounted higher


  • Only receives S.BUS-2 (telemetry) data (no Channel-Information)
  • Only receives data, when TX is running and UAV receives it's signal (it seems to be a power-saving feature, that telemetry is only sent, when TX (which usually receives it) is present)

Preparing the Receiver

You require the Robbe T-Box, which is using a modified RX which perfectly suits our purpose. Open the T-Box and remove the RX sitting in it.

Now take a PWM-cable and cut of one end, leaving a Male plug on the other end. Then solder the PWM cable onto the RX as follows:
  1. Ground
  2. 3.5 +V
  3. Data

Preparing the SIU2 USB-Adapter

In order for the RX to get the required 3.5V, we will modify the SIU2 adapter slightly. Carefully open the SIU2 adapter's plastic cover and wire a small cable from the marked spot on the PCB board to the middle Pin of the PWM plug (V+). The exact spot can be measured using a multi-meter. It provides 3.5V.

The PWM cable now plugs into the SIU2 adapter and receives it's required 3.5v from it.

Last edited Apr 26, 2015 at 2:17 PM by uTILLIty, version 3