三极管

My factory is enterprise of a state-operated, produce dynatron of crystal of medium, small-power.

【摘要】我家国营企业，生产中、小功率晶体三极管。

The phototransistor was installed through holes in the top of the case, and enclosed in a brass tube that was painted black inside and out.

该光敏三极管通安装洞上方的情况下，密封个黄铜管，这手绘的黑色内。