Sony RM-X1S conversion

The Sony RM-X1S remote control can be considered a downgraded infra-red remote control. It uses a NEC µPD6124A, 6600A microcontroller, but transmits the control signals via the cable. Marco Müller developed and built the modifications described below to convert the RM-X1S to a infra-red remote control.

RM-X1S infra-red conversion

Pin 4 of the µPD6124A is used as the cable output. This pin was originally intended for a control LED. The command is output on Pin 4 unmodulated.
You can attach two infra-red LEDs with a transistor (BC639 or 2SC2001) and resistor to Pin 5 of the µPD6124A to use it's infra-red modulated output. You could borrow the neccessary parts from an old unused infra-red remote control, since their output circuit should be all very similar.
The RM-X1S runs fine with 6 volt operating voltage (one or more batteries). You can either supply voltage with the original cable and a 6V power source or add some small batteries directly to the RM-X1S (possibly with a larger ring to provide more space).

To fit the additional parts into the RM-X1S case you will have to add a ring to the bottom plate. Marcus built the ring from transparent Makrolon, so he could add two blue LEDs for a fancy lighting scheme. The fotos below show the details.

1. Ausschnitt.jpg 140477 bytes
2. Einsatz.jpg 52128 bytes
3. PlatineModifiziert.jpg 118006 bytes
4. Probelauf.jpg 36869 bytes
5. RingFertig.jpg 53777 bytes
6. RingRoh.jpg 33506 bytes
7. Teile.jpg 98595 bytes
8. Scan of the ring dimensions 200dpi