What happens if the PC locks up during transmit?
A personal computer is a complex system, with hardware, peripherals, operating-system software, and application programs all working together. When a computer is used to control a radio transmitter, there is the possibility that a failure of any one of these components could cause the transmitter to be keyed continuously. As an option, EchoStation supports a unique fail-safe feature which helps guard against this possibility. It uses a special, external circuit which allows the transmitter to be keyed only while a continuous “heartbeat” is being produced by the computer. This heartbeat is generated from within the EchoStation software itself. If the heartbeat stops, the transmitter is disabled.
