 Ultrasonic Dog Whistle
One more circuit with famous NE555 timer circuit. This one produces ultrasound which can be heard by many animals. It's built to be "loud".
Magnetic Gun
This little gun can propel a small slug about 1.5 meters high, or 2.5 meters horizontally. It produces magnetic field using four coils and 4017b and NE555 which drive coils.
Magic Wand Conjuring Trick
This is circuit diagram of an interesting toy. It lights up if You move "magic wand" over it in the precisely right way that only you know!
Insect Repellant
22kHz oscillator which produces sound that should repel insect. It has adjustable frequency. Its built around one CMOS 4047 circuit.
Muscular Bio-Stimulator
This is a small, portable set, designed for those aiming at look improvement. The Bio-Stimulator provides muscles' stimulation and invigoration but, mainly, it's an aid in removing cellulites.
High Quality Intercom
A very high quality intercom, which may also be used for room monitoring
Sound Effects Generator
This circuit uses a UM3561 IC to produce four different sound effects
High Voltage Stun Gun
High Voltage Stun Gun. It's not a toy!
TV remote control Blocker
Just point this small device at the TV and the remote gets jammed.
Doorbell for the Deaf
This circuit provides a delayed visual indication when a door bell switch is pressed. Very helpful for deaf people.
Whistle Responder
Beeps when hears your whistle.
A gadget suitable for key-holders, games etc.
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