The present invention teaches a hands free headset of small size. With the
headset is a base transceiver unit which connects to the cell phone or
other device having audio input and output. The base transceiver unit may
advantageously contain a rechargeable battery to allow for mobile
operation, the headset transceiver unit may also use a small rechargeable
battery ("coin size") for reduced size and easy recharging. The base
transceiver unit may communicate with the headset via half or full duplex
transmission and reception. This may also be achieved in alternative
embodiments by digitally encoding one or both of the signals and
transmitting them as digital data. The antenna of the headset unit may be
located on or within the microphone tube, thus allowing a reduced headset
size. The base transceiver unit, which may be plugged into electrical
power wiring continuously or may be completely mobile may also save
energy in the form of electricity by avoiding an unnecessary "trickle
current". The battery in the base transceiver unit, and the battery in
the headset, may both be inductively recharged in the present invention.
Another space, weight and cost saving feature of the present invention is
the ability to automatically control volume. Automatic volume control
allows elimination of external volume control structure yet still allows
volume control to occur. In the present invention, volume is controlled
by the base device attached to the base transceiver unit. By this means,
battery life may be extended yet without the cost and bulk of an external
control device such as a switch of a size suitable for a user's fingers
to operate.