摘要 |
A metal detector 1 has a sensor 2 which outputs a signal indicative of the detection of metal. A transmitter 8 transmits a wireless transmission representative of the signal produced by the sensor. This transmission, which may be infra-red, ultra-sonic or radio frequency, is received by a receiving unit 10 which is connected to an audible output means 11 which outputs a signal representative of the sensor signal. This enables the audible output means 11 to be at a location remote from the metal detecting sensor 2 and transmitter 8, and output a signal which varies in response to the detection of metal by the sensor. The audible output means are typically provided as headphones worn by the user. Wireless transmission from the detector thus has the advantage that the user does not have to remove the headphones every time the detector is put down to dig for objects. |