| 摘要 |
<p>An R.F. radiation free hands free kit has a plug and wire to pick up the audio electrical signals. The first converter 2 which contains the electronic circuit 3 and opto transmitter 4 to convert audio electrical signals to audio light signals. Fibre optic cable carries the audio light signal without R.F. pick up to the second converter 6. The second converter 6 has an opto receiver 8 to convert light audio signals to audio electrical signals. The electronic circuit 9 drives the earpiece 13. The metal wire (12) connecting the earpiece to the second converter 6 is of a short restricted length to reach the users ear from the shirt collar where the second converter 6 will be. This is so the metal wire (12) cannot come near the phone or its aerial.</p> |
