Countdown test demonstration

I obtained a DirectLogic 205 PLC this past weekend. The trainer module only has 4 outputs, but that was enough for me to practice programming a launch timer connected to my S-IB Operations panel. It's shown here as a proof of concept:



I only threw one switch, which started the countdown clock at T-10 seconds. The rest of the lights went on via program control: ignition at T-3 seconds, all engines running at T-1.75 seconds, and liftoff at T-0. This was the sequence for the Skylab 2 launch.

I ran wires directly from the D2-08CDR relay interface on my DL205 to the terminals at the back of the Roto-Tellite enclosures.

This will be a fabulous way to drive the display!