BLOCKsignalling ASP1A Manual

ASPECT CONTROLLER ASP1A
(FOR COMMON CATHODE LED SIGNALS)

Uses an infra-red sensor mounted below the track to detect trains passing above

When a train is detected, the module triggers the signal to switch to red

Signal automatically switches back to green (through yellow and double-yellow if
appropriate)

Flexible programming options to suit different signals and to allow adjustment of
timings to suit

Designed for signals which need +12V to be switched to them to light their leds
(common cathode)

Realistic fading between aspects.

Yellow and Double-Yellow stages will change to red if another train passes.
Building on the success of our infra-red train detectors, this module boasts a wider
range of input voltages, smooth fading between aspects, and the ability to be
triggered from yellow or double-yellow stages back to red.
This Signal Controller detects trains by bouncing invisible Infra-Red (IR) light off the
underside of the rolling stock, and detecting the light reflected back. Once triggered
by the train, the module runs built-programs to simulate the operation of 2-, 3- or 4-
aspect signals.