Skin conditioning indicator

Claim 1

A constant current temperature measuring apparatus comprising: a power source; leads from said source to provide separate paths for current flow, said paths being characterized as a first leg of the circuit and a second leg of the circuit; a first field effect transistor in said first leg of the circuit; a second field effect transistor in said second leg of the circuit; means connecting said source to the drain terminals of said first and second field effect transistors; resistance means in each of said first and second leg of the circuit, each said resistance means being connected to a respective source terminal of said first and second field effect transistors, said resistance means in said first leg including a variable resistance whose control arm is connected to the gate of said first field effect transistor and said resistance means in said second leg being connected to the gate of said second field effect transistor; a first terminal in said second leg of the circuit at the point of connection of said resistance means with the gate of said second field effect transistor; a second terminal in said first leg of the circuit after the variable resistance; an indicator connected between said first terminal and said second terminal; and means to recombine said separate paths of said first and second leg of the circuit, said means to recombine having a first switch in said second leg, a calibration means in said second leg beyond beyond said first switch, a probe device in said second leg, a resistor in said first leg, a lead connecting said first leg and said second leg and a second switch connecting the lead to the source in completion of the temperature measuring apparatus.