In couple of of my earlier content we mentioned a couple of GSM remote control circuits making use of normal cell phones as the modem. Almost all of those designs integrated the ringtone of the cell phone as the initiating signal. Within this submit we’ll find out how the same might be accomplished but by utilizing the vibrating function of the modem cell phone.
In our prior GSM remote control designs we utilized those cellphones as the modem which in fact had the particular ringtone choice facility for a particular designated number, right here the modem will likely have a vibrating characteristic for the precise allocated number chosen as the initiating number, this will be significant to be able to attain a fool proof operation of the system.
The idea is plain, it’s to identify the vibs. from the cell phone body, transfer it into a toggling signal and manage the preferred load or gadget ON or OFF.
For detecting and utilizing a vibrating signal to activate a relay, we are going to require a vib. detector circuit as demonstrated in the following diagram:
The circuit is actually a transistorized high gain amplifier where a piezo is utilized as the vib. sensor.
The vibrating from the piezo produces a in the same way oscillating voltage at the base of T1 which can be properly heightened by all the following transistor phases comprise of T2, T3, T4, T5, T6 and the connected parts.
The amplified DC signal is lastly used across the linked relay which toggles as a reaction to the identified vibrating over the piezo.
Considering that a cell phone might well have an unreliable vibrating rate could possibly lead to a related oscillatory reply over the relay switching. To stay away from this a high value capacitor in the range of 500uF ought to be attached instantly across the base and emitter of T6, this may make sure that T6 maintains its conduction at the same time the cell phone vibs are occasionally missing.
In the above mode, the relay remains initiated only for provided the vibrating signals are made, in an effort to translate the reply into a toggling impact a flip flop circuit turns into crucial. The following easy 4093 IC based design evolves into completely appropriate for the needed conversions.
The input result in might be linked to the pole of the relay, while the N/O of the relay will have to be associated with the positive of the supply.
On the other hand, the relay could possibly be completely eradicated, and the “input trigger” of the above flip flop circuit straight linked with the collector of T6.
As soon as this is achieved the relay would react with an alternate ON/OFF toggling motion each time the modem cellphone is called by the owner or the user.
The deliver of the flip flop could be utilized for switching any most wanted appliance or in case it’s deployed inside a vehicle might be used to function the central locks and the ignition system for attaining a total cell phone operated security function.
C1 in the very first vibrating detector circuit could possibly be a 0.22uF capacitor and has to be applied only if the piezo is shut down over a longer distance from the circuit, elsewhere C1 could possibly be disregarded.
Ideally the piezo needs to be located close with the circuit board.
The piezo transducer is a 27mm common device which can be typically making use of in piezo buzzer circuits.
It has got to be correctly stored inside a plastic enclosure for insuring an optimal response from this.
The whole unit could be more enclosed inside a plastic box with the piezo assembly stuck on inner top surface of the box.
The modem cellphone ought to be instantly positioned over the above enclosure right on the outer opposite surface of the piezo assembly (see figure below)
The modem will have to be properly protected over this place to ensure that the unit will not drop away from the box while vibrating.
Right now your cellphone vibrating based remote control circuit is ready and can be utilized for almost any preferred GSM based remote control application and might be turned from any part of the world, simply with a flick of a button.
Ensure that the vibrating feature is allocated to switch on only for the specific numbers and not for the default numbers to make sure a quick and easy procedure of the unit.