| 摘要 |
<p>PURPOSE:To prevent an excessive current from flowing through a pulse high- output amplifier by providing a variable attenuating circuit which increases the level of a signal supplied to the pulse high-output amplifier with time between a pulse transmitter and a divider. CONSTITUTION:A switch 6 in the divider 4 is opened in observation mode. A trigger signal D1 for transmission from a controller 3 is supplied to the pulse transmitter 1, which outputs a sent signal to the variable attenuating circuit 2 in synchronism with the signal D1. The circuit 2 incorporates a digital or analog operation type attenuator and is so constituted that the attenuator quantity decreases gradually. The sent signal which is attenuated is inputted to the pulse high-output amplifier 7. Therefore, the excessive current at the start of the observation mode is reduced greatly and the load on the power source system of the radar device can be reduced greatly. Further, the circuit 2 has the function of a step-up attenuator which is incorporated in a conventional calibrator, so the constitution is reduced in size and weight.</p> |
