| 摘要 |
PROBLEM TO BE SOLVED: To adjust a sending level of even such a device as a modem without adding a special circuit, etc., by registering a correction sending level of a sending level correction table that corresponds to an attenuation amount of a calculated special signal and making the attenuation value the sending level of a sending level setting circuit. SOLUTION: A sending level can be adjusted by changing an attenuation value of an attenuator 9a of a sending level setting circuit 9. A sending level automatic adjustment processing detects an incoming answer tone from a computer of a center, uses an attenuation amount calculating program that is stored in ROM/RAM 6b and calculates the attenuation value. The calculated attenuation value is collated with a sending level correction table 6d, a corresponding sending level is decided and it is registered in a register 6c. After that, the attenuator 9a of the circuit 9 is controlled by the attenuation value registered in the register 6c, negotiation with the computer of the center is carried out and data is transferred. |
