| 摘要 |
PURPOSE:To use a relay having small contact capacity and a transformer for low current, by using a transistor (TR) and resistors for a transmission circuit. CONSTITUTION:Through pressing of a transceiver 1, contacts 1-1 and 1-3 of the transceiver are short-circuited and a contact 3 make-contacts by the operation of a relay 2. A base current is applied to a TR10 via a power supply source 4, a breeder resistor 8, a relay contact 3 and the secondary winding of a transformer 6. On the other hand, a transmitting current flows via the voltage source 4, current limiting resistor 5, TR10, contacts 1-2, 1-3 of the transmitter 1, then the transmission signal is applied to the transformer 6 via a coupling capacitor 9 and transmitted from an output terminal 7. Thus, since the base current is minute, the transformer 6 and the contact 3 can be used in the low-current type. |
