The components of the Transponder key
The complete key
Side cover opened showing transponder pod
Highly enlarged picture of the transponder module.
The coil of wire (less than half the thickness of a human hair) picks up the charge from the aerial of the control unit (usually hidden behind the cowling around the ignition switch). This charges the microcapacitor (very top metallic chip), this inturn powers the coded chip below which sends a coded signal via the coil back to the main Apollo control unit. If the code is correct the Apollo 780 will disarm and allow the vehicle's engine to start.