MD-005 Station Control
The MD-005 station control module provides semi automatic signalling at a through
station on a model railway. It is designed to work with two aspect signals that are fitted
with LED indicator lights.
The signal LEDs can be wired as either common anode or common cathode.
The MD-005 provides the voltage required for operation of the LEDs in the signals without the need for separate resistors.
The MD-005 comprises a single circuit board assembly that includes a microprossessor
and inputs for the track sensors and a relay to provide optional track section isolation.
The track sensors are light dependent resistors that are located in the track
adjacent to the signals. A push button is used to set the starter signal to green to
allow the train to leave the station.
The module requires an external regulated power supply of 12 to 14 V DC.
The MD-005 module is designed to operate signals fitted with LED lamps. However,
by combining it with an MD-003 servo motor drive module it can be used to operate
semaphore signals, the Application Note at the following link explains how -
The sequence of operation of the module is as follows, refer to the Figure below.
- 1. Initially the home signal is set to green and the starter signal is set to red.
- 2. As the train approaches the station and passes the home signal it trips the home
signal sensor and the signal sets to red.
- 3. At the same time the isolated section of track (if fitted) is deactivated.
- 4. The train enters the station and stops at the starter signal, either
automatically at the isolated track section or manually under driver control.
- 5. When the train is clear to leave the station, the starter signal set pushbutton is pressed.
- 6. The starter signal is set to green and the isolated track section is activated and
the train can leave.
- 7. As the train passes over the starter signal sensor it trips and sets the starter
signal to red and home signal to green ready for the next train to arrive.
- Control of 2 two aspect signals
- Semi automatic operation
- Ambient light sensitivity adjustment
- Common anode or common cathode LED wiring
- Optional track section isolation
- Controls two signals home and starter
- Input Voltage - 12 to 14 V DC from external power supply
- Output - signal to LEDs
- Sensors - Light Dependent Resistors
- Maximum output current - 12 mA per signal
- Circuit board dimensions - 62 x 38 mm