Systems, methods and related apparatus for determining physiological parameters

A thermometer for connecting to an audio interface of an electronic device, the thermometer comprising:

• a jack plug having first and second contacts for receiving first and second harmonic driving signals from the electronic device and a third contact for returning a response signal to the electronic device;
• and
• a temperature sensor consisting essentially of a thermistor connected between the first and third contacts and a reference resistor connected between the second and third contacts.

An adaptor for connecting to an audio interface of an electronic device, the adaptor comprising:

• a jack plug having first and second contacts for receiving first and second harmonic driving signals from the electronic device and a third contact for returning a response signal to the electronic device;
• and,
• a pressure sensor having a pressure sensitive area, the pressure sensor connected as a bridge across the first and second contact to provide the response signal to the third contact, between the first and third contacts and a reference resistor connected between the second and third contacts.