该机曝光限时电路由稳压、同步触发脉冲、主可控硅触发、限时电路、限时保护电路5部分组成。稳压电路输出＋15V稳定直流电压，同步触发脉冲电路是为获得一串与电源同步且超前10°的触发脉冲，而后去触发可控硅，主可控硅触发电路由振荡器和功放组成，其作用是使主可控硅受触发 The machine exposure time limit circuit consists of five parts: voltage regulator, synchronous trigger pulse, main thyristor trigger, time limit circuit, and time limit protection circuit. The voltage regulator circuit outputs a stable DC voltage of +15V. The synchronous trigger pulse circuit is to obtain a series of trigger pulses synchronized with the power supply and advanced by 10°, and then to trigger the thyristor. The main thyristor trigger circuit is composed of an oscillator and an amplifier. The role is to trigger the main thyristor