Abstract: An arm support comprises a shoulder saddle and an arm cuff for suspending the arm with a plurality of suspension straps extending between the cuff and saddle for unloading the weight of the arm from the shoulder joint while the plurality of straps permit a wide range of motion of the shoulder joint and positive support for the arm.

Abstract: An induction balance metal detector circuit includes a receiver coil output which is connected to one input of a unique phase detector circuit. The reference transmitter coil signal is connected to a second input of the phase detector. The phase detector comprises circuitry which provides an output equal to the smaller of the two input signals. The output is doubled and integrated, then compared to a current indicative of the integrated reference signal in a differential amplifier. The output of the differential amplifier is passed through a dead band and used to excite a first indicator in response to phase difference between the inputs to the phase detector indicative of the location of ferrous metals. A second indicator is excited in the event the phase difference indicates the presence of non-ferrous metals. A balance and threshold control is established between the transmitter and the receiver coils in order to adjust the phase and amplitude of the received signal.