On this page we understand more about an easy infrared based remote control door lock circuit which you can use for securely locking doors by way of unique foolproof IR frequencies.
The offered infrared remote control circuit may be used for locking your main door, gate, garage door, shop or any entrance which might prefer a simple internal locking by way of a remote control system.
The above diagram reveals an excellent IR based remote receiver design, through which the IC LM567 forms the IR frequency decoder while the IC 4017 forms the flip flop stage.
D1 is a photodiode sensor which turns the IR frequency from the IR transmitter into a respectively pulsating voltage across R2.
This pulsating voltage is imagined and identified by the pin3 of the IC LM567, if the frequency of the pulse complements with the fixed frequency of the IC it promptly sets off its output pin8 with a low logic pulse.
The IC frequency is fixed by finding R1/C1 correctly which evolves into the unique code of that certain remote control process. Any kind of value between 10 Hz to 500 kHz could be set making use of these RC timing components of the IC.
When a matching frequency is determined across R2, pin8 of the LM567 is offered with a low signal.
This generates the associated BC557 submitting a positive pulse to pin14 of the IC 4017.
Pin14 being the clock pin of the IC 4017 creates a resulting shifting high across its presented outputs, determined by the initial status either a high or a blank signal is established at the base of the linked BC547 relay driver stage.
This allows the relay to toggle over the particular position forcing the solenoid device towards a locking or an unlocking position.
C3 is particularly released that allows you to delay the result of the relay toggling, indicates that the far away transmitter might want to be pressed for a few seconds so that you can execute the above locking/unlocking processes. This is quite certain that an intruder or a hacker cannot really impact the Rx by way of a varying/sweeping frequency creating device.
The following image indicates the IR transmitter handset for the above RX unit, which evolves into the remote control handset for locking or unlocking the door.
The above Tx is an easy RC based two transistor oscillator, which might be employed as the Tx remote handset for the suggested IR door lock circuit.
The 3V is employed by way of a push button switch activating the pulses through the IR diode towards the photo diode of the above discussed Rx circuit.
In this particular Tx circuit also the R and C components ought to be suitably picked such that the transmitted frequency specifically fits with the set frequency of the Rx circuit.
The pertinent formulas could be researched in the following article
http://homemadecircuitsandschematics.blogspot.in/2015/02/infrared-remote-control-security-lock.html
After assembling the circuits the units could be certified externally to establish the relay toggling in keeping with the Tx IR frequency.
The moment this is accomplished, the Rx circuit might be aptly enclosed inside a sturdy box and incorporated with the door from the interior for the designed locking/unlocking