Whether it is for spying on somebody or something, or for safeguarding a particular object, this tiny tracker transmitter will serve the purpose with extreme efficiency.
This transmitter is so small that it would easily fit inside dollar sized circular enclosure and could be installed within a necklace locket, belt, on pen cap or anywhere you wish to accommodate it into.
Once installed, the pulses generated can be tracked or listened over a radial distance of 10 meters over any FM based radio receiver or transistor.
The concept of the design includes a small single BJT based FM frequency generator in the range of 80 to 110 MHz, and a complimenting single IC pulse generator stage.
The pulse generator is made around the IC LM3909, and rigged to produce a pulse at the rate of 0.5 Hz.
This frequency is fed to the base of a transistor which is wired as a FM frequency generator in the range of 90 to 110 Hz. This frequency is selected to match the standard frequency range of all FM radios universally.
The pulses injected at the base of the BJT modulates the FM frequency into bursts of these pulses which is radiated in the atmosphere across a 10 to 20 meters radial space.
Once installed this tiny transmitter tracker will allow the owner to track the pulse sound over a mobile based FM receiver of simply any standard FM radio.
AS long as the target to be tracked is within the desired safe range, the pulses are successfully received and tracked by the owner. In case the target moves away out of the safe zone, the beeping stops, and the owner is quickly alerted regarding the change of location of the object or the target.
The circuit utilizes only 1.5V, which could be a small button cell. Since the design works in a pulsed manner, the consumption is very low and may last for many many days of continuous
This tracking transmitter can also be used as a pet tracker or a kid tracker.
Circuit Diagram:
