Fairchild's Model 21 is an adjustable ratio Pneumatic Relay, whereby the ratio of output pressure to signal pressure is infinitely adjustable.

飞兆半导体的21型是一种可调比气动继电器，即输出的压力信号的压力比是无限可调。

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The Model 21 Adjustable Ratio pneumatic relay has a signal chamber lever arm, whereby the ratio of output pressure to signal pressure is infinitely adjustable.

真21比气动调节继电器信号室力臂，即输出的压力信号的压力比是无限可调。

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The Model 21 Adjustable Ratio pneumatic relay has a signal chamber lever arm, whereby the ratio of output pressure to signal pressure is infinitely adjustable.

真21比气动调节继电器信号室力臂，即输出的压力信号的压力比是无限可调。

youdao