Color expansion photo timing exposure and sound and light signal transmitter circuit

Photocoupler

The step-down rectifier circuit is composed of a step-down transformer T, a full-bridge rectifier QU and a smoothing capacitor C1, and the rectified DC voltage is regulated by R1 and DW1 + 6V DC voltage.
During the high-level period of IC1 output, VT1 is saturated and the relay K is energized. The electromagnetic coil is energized and energized, so that the constant contact J1-1 is turned on, the bulb H is electrically lit and exposed, and the timing is turned to a low level at 555. , J is released, J1-1 is disconnected, and the H light is extinguished. J1-2 is the normally closed contact of relay K. It is in the off state during K energization; VT1 is cut off, J1-2 is closed again, IC2 is energized, and a call occurs.
IC2 uses a triode type music integrated circuit VT66A type. It has two trigger modes, S type and L type. Here, the S-type is selected. When the J1-2 is closed, the device is powered and triggered once, and a piece of memory is immediately released. The device stops at the end of the song and the device is still static. Vt66A type built-in power output transistor, its output 3 feet can be directly connected to 8Ω Speaker sound, no need to connect external triode to drive. The maximum output power of VT66A can reach 300mW, and its quiescent current is not higher than 0.5uA. Therefore, although J1-2 is a normally closed contact, its consumption electrode is slight. The working voltage of VT66A is 1.2~3.6V. In order to ensure the normal use of the device, the R4 and DW2 voltage regulator circuits are designed, and the 2CW51 is regulated by +3V to supply power.