The MTS Trailblazer Sign is Changeable
Message Sign.
General:
McCain The choice of changeable message is selected by the
user in advance of construction. The Trailblazer uses LED
clusters for illumination. The Sign Control Unit is a 104
PC Bus embedded standard PC-AT computer. Commands to change
sign messages are received by the Sign Control Unit on an
RS232 serial port which can connect directly to any of the
following: