Delay lamp circuit using time base circuit (2)

It is another delayed light circuit using the NE55S time base circuit. SB1 and SH2 are both light-kill buttons,
which can be installed in two different places and both can operate the light E.
  After pressing F SB1 or SB2,
the lamp E will be powered on and light up. At the same time,
the AC voltage is step-down and VDl-
VD4 bridge rectifier, and a
DC voltage of about 12 can be output at both ends of the ￡j
. At this time,
the ② pin of the NE55j time base circuit is low level due to the closure of contact k 2 , and the time base circuit is set. The ③ pin outputs a high level, the relay K absorbs the platform, and its moving platform contact k_1 closes, causing the circuit gate Lock; movable contact k-2 jumps open due to R, R. The voltage divider stabilizes the level of pin ② at 】/2v_m, and the circuit status will not change, so the light E continues to light up. The power supply then passes through resistor R. When charging to 2/3 of the power supply voltage, the basic circuit is reset, C, the stored charge is quickly discharged to the internal NE555 through the ⑦ pin and the three tubes are discharged - preparing for the delay of turning on the light next time. At the same time, relay K is turned off, contacts k1 and k-2 are reset , and light E goes out. The characteristic of the book circuit is that after turning off the light, the circuit is small and no longer consumes any power. The relay K gallery uses a small electromagnetic relay with two switches to switch electric shock, such as JRX-13F, DC12V type, etc.