Reading time: 2 minute A cheap charger for charging batteries with Ni-Cd or NiMH elements is easy to build using the 555 timer and a few transistors. Charging is done quickly, and the electronic scheme ensures the elimination of the unwanted memory effect in NiCd cells.
Reading time: 2 minute The electronic DIY project presented uses power transistors at the output ("H" Bridge Output Stage), but in the TO92 capsule. The control part, Signal Generation Circuitry, is built with 2N2222 transistors. The speaker, connected to the Output, must have an impedance of approx. 6 Ohm.
Reading time: 3 minute The presented speed variator, destined to supply the mini-drills for drilling or milling the wiring, offers a wide adjustment range and a high torque at the motor shaft. The assembly is simple to do, the article presenting detailed indications for operation and assembly.
Reading time: 2 minute The classic "bell button" (simple return switch) can be and even is replaced, in many mini-automation assemblies, with a resistive sensor (touch). The example described in the article illustrates this "replacement" in the case of a common multivibrator circuit with transistors, used as a bell.
Reading time: 2 minute The DIY project in the article presents the scheme of a simple intercom made with the LM386 integrated circuit. The two 8-ohm speakers are used as microphones at the same time.
Reading time: <1 minut The DIY project presented is a mini FM transmitter, easy to build. The installation is ideal for surveillance of a room, surveillance of children, with a range of up to 400m.
Reading time: 4 minute This assembly complements the "10W Amplifier" 8109 set and is followed by the third "Audio Mixer" 8203 assembly set. All these 3 vintage DIY electronic kits together form an audio frequency amplification chain, having absolutely all the elements necessary for a classic amplifier. . The preamplifier with tone corrector is made with 6 silicon transistors, distributed on several floors.
Reading time: 2 minute It presents a simple dynamic light scheme, recommended for beginner builders. The assembly is able to generate multiple dynamic variants such as: sequential operation (direct and reverse) and a pseudo-random one.
Reading time: 2 minute For those who want to build a sequential dynamic light for 8 LEDs, this electronic DIY IPRS kit is recommended because its construction is extremely simple. The assembly is based on 3 integrated circuits: CDB 404 (SN74F04N) - the clock generator and two CDB 495 travel registers (SN 7495 / 74LS95B).
Reading time: 5 minute The vintage DIY electronic kit presented is an electronic assembly called "Audio Mixer", because with the help of voltage amplification stages the "mixture" of audio frequency signals provided by the microphone, tape recorder, electromagnetic dose or crystal is achieved. Of course, the assembly can be adapted for other types of inputs.