Someone beat me to it: http://i-hacked.com/content/view/176/44/.
I'll have (someday) a new version which should be using a PLL circuit for precision pulse control, this will make the circuit temperature stable.
Notes / Patents
- Rostislav Persion's Opticom Notes From the old voltsamps.com website.
- TOMAR E-Lock Emitter Authenticator New, secure traffic prevention system.
- The MIRT Mobile Infrared Transmitter (MIRT) for emergency vehicles.
- Traffic Light Changer - Rev 02 Plans-and-Kits schematic (86k PDF)
- 3M Opticom Priority Control System (156k PDF)
- 3M - Moving at the Speed of Life (1.2M PDF)
- Emergency Traffic Control System with Security Transmission Control U.S. Patent 4,016,532 (732k PDF)
- Remote Control System for Traffic Signal Control System U.S. Patent 4,162,477 (3M) (1M PDF)
- Optical Traffic Preemption Detector Circuitry U.S. Patent 5,187,476 (3M) (1M PDF)
- Optical Traffic Preemption Detector U.S. Patent 5,202,683 (3M) (1M PDF)
- Vehicle Tracking System Incorporating Traffic Signal Preemption U.S. Patent 5,602,739 (3M) (1M PDF)
- Emergency Vehicle Traffic Signal Preemption and Collision Avoidance System U.S. Patent 6,326,903 (1.2M PDF)