Here is a circuit that can be utilized as a part of workplaces, stores, stockrooms, and so on amid night to check whether the gatekeeper of your foundation is on obligation. For operation, it utilizes a current phone (e.g. in office or store) nearest to the guard's post. The guardian is given a sound ready flag by simply ringing the workplace/store phone once (least) from your home or some other place, ideally utilizing your cell phone. The ring is identified by the given circuit and the guardian is additionally given a visual ready flag by a sparkling light.

The light stays "on" for a span of about 60 seconds not long after the ring tone. The guard is given a direction to enlist his nearness by just guiding his light bar towards a divider mounted LDR sensor unit (without lifting the handset off-support of the ringing phone). This is to be done inside the day and age amid which the ready light gleams. In the event that he neglects to do it inside the passable time, the circuit enlists his nonappearance by augmenting a number. In the event that he does, the check stays unaltered. Up to nine separate ready rings are considered here. The tally showed is the quantity of times the gatekeeper neglected to enlist his nearness. The cell phone records the called number and call time, and it can be utilized with the showed number to get the planning points of interest.

The phone lines (TIP and RING) Counter 74LS192 (IC7) is reset to zero state by making its reset stick 14 high through reset switch S1. The 7-section, regular anode show DIS1 is driven through IC 74LS47 (IC8). At the point when the telephone rings, check "1" is shown after about one moment. This happens if the guardian neglects to center the torchlight bar on LDR1. On the off chance that LDR1 gets light from the light of the gatekeeper inside the permitted era, the down clock stays high until the up clock is high.

The counter tallies up and afterward down, thus, as a result, the tally stays unaltered. All segments, aside from LDR1, are kept in a fixed bureau with locking course of action. As it were LDR1 is divider mounted and unmistakable outside. This is done to stay away from manual resetting of the counter. The circuit is to be controlled by a battery to abstain from resetting of the check amid power disappointment.
The working system can be condensed as takes after:
1. At first, when the power supply is exchanged on, power-on-reset parts C8 and R13 reset counter IC7 and the show indicates "0."
2. Presently dial the phone number (where parallel framework is introduced) from outside or from your versatile. For the main ring, transfer RL1 stimulates and ready light L1 gleams.
3. When ready light L1 is off, the counter is increased by "1."
4. On the off chance that the guardian centers the light bar on LDR1 inside the sparkling time of ready light L1, the counter first tallies up and after that numbers down lastly the show demonstrates 0. This shows that the guardian is available.
5. In the event that the guardian centers the light shaft on LDR1 after ready light L1 goes off, up counting happens and the show demonstrates "1." This demonstrates the guardian is truant.


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