The Biophone is a combination voice and telemetry radio communications system used in the 1970s and '80s by paramedics to talk to the physicians supervising them from a hospital base station. The key difference between this unit and another two-way radio was that it had the ability to transmit a patient's electrocardiogram.
The Biophone was produced by the Biocom Company. The Biophone 3502 used the internals of a General Electric PE-series handheld radio mounted into an orange case, which was made of an orange laminated fiberglass with aluminum trim. The Biophone had an internal rechargeable battery that powered the sensor equipment, the radio, and an amplifier that raised the transmitting power to 50 watts. The unit had a connector for a vehicle-mounted antenna allowing better signal reception and transmission from the back of an ambulance. The Biophone could have any 6 (the maximum that could fit in the PE radio) of the 10 UHF medical duplex channels in the 450-470 MHz range. This allowed flexibility in the overall system. The NiCad battery could be charged up in 15 minutes.[citation needed]