the last two ends of the circuit connect with a switch k 1 and a resistor r 1 in series respectively to form a loop herein k 1 is a switch on the side of the pen functioning as the right button of a mouse a waveform of a transmitted electromagnetic wave according to the present invention is shown in fig2 wherein its cycle is of odd times of a resonance cycle determined by the resistors and capacitors in the pen the transmitting and receiving circuit of the present invention is illustrated in fig5 wherein the part in the direction of y is a continuous transmitting circuit by sequentially gating the transmitting circuits y 1 y 2 y 18 y 24 and regularly gating the receiving circuits x 1 x 2 x 18 x 24 in turn the position in y coils can be determined for the pen according to the strength of a received signal that is which y coils the pen locates can be determined similarly by regularly gating the transmitting circuits y 1 y 2 y 18 y 24 in turn and sequentially gating the receiving circuits x 1 x 2 x 18 x 24 which x coils the pen locates can be determined also following is the practical connection of the circuit the transmitting circuits are in the direction of y and the receiving circuits are in.