Title:
PROTECTING DEVICE FOR RADIATION MEASURING APPARATUS
Document Type and Number:
Japanese Patent JPH01185479
Kind Code:
A
Abstract:
PURPOSE:To ensure the protection of a radiation measuring circuit when a main power source is turned ON, by providing monitoring means, which monitor the output levels of an amplifier, a high voltage power source and the main power source. CONSTITUTION:A switching element 21 is provided between a radiation detector 1 and an amplifier 4, and cuts off a detected signal, which is sent to the amplifier 4 under the closed state of the element 21. Monitoring means 23 of a diagnostic circuit 22 monitor the respective output levels S1-S3 of the amplifier 4, a high voltage power source 2, which supplies the high voltage to the detector 1, and a main power source 7. When at least either the level S2 or the level S1 is decreased lower than a specified level, the element 21 is closed on the result of the monitoring. When the levels S2 and S3 reach the specified level, the element 21 is opened. In this way, the input of the detected signal into a radiation measuring circuit 20 is cut when the main power source 7 is turned ON. Since the input of the detected signal into the circuit 20 can be cut off, the circuit 20 is protected. Since the output levels S1 and S2 are monitored, the input of the detected signal into the amplifier 4 can be performed at the optimum timing.
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Inventors:
HONMA TAKAO
Application Number:
JP988888A
Publication Date:
July 25, 1989
Filing Date:
January 20, 1988
Export Citation:
Assignee:
TOSHIBA CORP
International Classes:
G01T1/17; G01T1/185; H03F1/42; H03F1/52; (IPC1-7): G01T1/17; G01T1/185; H03F1/52
Attorney, Agent or Firm:
Takehiko Suzue (2 outside)