What can you do with a remote control?

The usual path of a home craftsman: we need a certain device, we begin the search for materials and manufacturing technology. We will consider the exact opposite option: there is an initial blank (a working, but unnecessary remote control), but it is not clear how to use it.
Any infrared control panel is built on the generation of a high-frequency signal containing information.
Therefore, in its circuit there is a generator and an information transmission device: IR Light-emitting diode. If you connect another device instead of the emitter, you can expand the scope of application of the remote control and breathe new life into an old device.
Functionality check
Removing infrared Light-emitting diode, connect the power and short-circuit any button on the remote control circuit (connect the tracks on the board).


We connect a speaker to the output - it produces sound in accordance with the frequency of the generator.

If you connect a regular (not IR) to the output Light-emitting diode, we will see intense flashing. By connecting a high-frequency transformer from a switching power supply to the output, you can light a neon lamp.
We connect the oscilloscope.The measured frequency is 32 kHz (this parameter may be different), the peak voltage is about 45 V. Therefore, this circuit can be used for serious crafts.

Practical use:

Flasher strobe

You can connect a regular one to the output of the circuit Light-emitting diode, or a more powerful assembly (with a supply voltage of 35 V) using an HF transformer. A step-up transformer with the following characteristics: primary winding 10-12 turns, secondary winding 300-350 turns, will ensure reliable start-up of a powerful LED element. You can assemble an effective means of shock self-defense.

High voltage spark generator

Developing the idea with a step-up transformer, we assemble a multistage voltage multiplier. Using low-power capacitors and diodes, we can easily achieve a 2-3 mm high-voltage discharge. By increasing the cascade, you can achieve a spark 15-20 mm long. However, in this case the generator will work with excess load.

Hidden wiring detector

We can generate high frequency pulses and transmit them using an antenna. If you use indoor wiring as an antenna fabric, you can pick up the signal using a conventional long-wave radio. To do this, we connect a coil of 10-15 turns to the output of the circuit. At the same time, solder a regular power cable with a plug.

Important! When checking hidden wiring, the power supply to the site must be completely turned off. Otherwise, you can get electrocuted, not to mention the homemade “device” burns out.
When the circuit is turned on, the generated high-frequency signal is sent through the socket to all wires in the walls of the room. Using a radio, it is easy to find the route of hidden wiring.

Demonstration application, not practical

Two large diameter coils (100-120 mm) demonstrate inductive transmission of electricity over a distance. This is how wireless chargers for smartphones work. The primary coil is soldered to the output of the remote control board. Second coil with load (Light-emitting diode) is brought to the first, the diode lights up.

By winding a coil on a paper tube, you can assemble a high-frequency field generator. The primary winding (4-5 turns) is connected to the output of the circuit, the secondary winding (300-400 turns) is connected at one end to the base of the output transistor on the board. The second end is free. When a ferrite rod is inserted, an electric field is generated that can ignite a fluorescent lamp.

Result:

The only drawback of such homemade products is low reliability. This is compensated by the conditional free materials.
To comply with safety measures when creating a stun gun, it is necessary to use a durable dielectric housing.

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