Project for the Fieldday at Wirberg 2011.
The board can be attached to a ham Radio transceiver. If a 1750 Hz tone is detected, the current temperature and / or the status of two inputs will be returned. The info will be provided via CW, or with a simple tone sequence (i.e. -13 degrees = “long pause short pause short short short”). The inputs can initiate a transmission themselves, meaning the unit acts like an alarm system. Updatable via ISP connector.