This ding-dong door bell circuit might become the simplest and cost-effective door bell circuit. The circuit is designed based on single IC 8021-2 which manufactured Formox Semiconductors. It is an 8-pin DIP (Dual Inline Package) IC whose only four pins, as shown in the above circuit design, have been used.
This is the simple spring reverb guitar effect circuit that can be built low cost and just requires a minimal amount of electronic parts and of course need minimum space for the circuit it self. The circuit also easy to built, it need 9V DC supply to work.
This is the schematic diagram of Infrared (IR) cordless headphone. Maybe it also can be called “wireless headphone”, but it use infrared as sound signal carrier. It use a pair of circuit diagrams that are IR transmitter and IR reveiver. Using this low-cost project one can reproduce audio from TV or other electronic devices without… Read More »
This easy to built circuit produces a warning beep when somebody crosses a secure area in your home or place of work. The transfer, hidden beneath the ground mat, causes the alarm whilst the individual walks over it. The circuit makes use of a behaviorive foam because the switch. it may be small items of… Read More »
This kind of circuit is a helpful device for testing of infrared (IR) based remote control transmitters utilized for TVs and VCRs and so forth. The IR motions from a remote control transmitter are sensed by the IR sensor module in the analyzer and its output at pin 2 goes low. This thusly switches on… Read More »
This is the light fence schematic diagram uses LDR as the light sensing. The fundamental issue with the greater part of standard light sensors is that they require exact arrangement of light bar to quiet the circuit throughout standby mode. The circuit portrayed here is sensitive to the point that it will catch a moving… Read More »
This is variable DC power supply circuit, or we can call it adjustable DC power supply which give us a 1.2V-25V output voltage. The power supply schematic above is taken from the datasheet of regulator LM338K manufactured National Semiconductor. The circuit uses IC LM338K as the voltage regulator, so we will get the stable and… Read More »
Here is the circuit diagram of stereo digital volume control. This circuit could possibly be applied for upgrading your manual volume management within a stereo amplifier circuit. In this particular circuit, push-to-on switch S1 controls the forward (volume enhance) operation of the two channels while a identical switch S2 controls reverse (volume reduce) operation of… Read More »
Here the SW transmitter circuit based on IC BEL1895. This particular transmitter circuit works in shortwave HF band (6 MHz to 15 MHz), and can be applied for shortrange communication and for educational purposes. The circuit is composed of a mic amplifier circuit, a variable frequency oscillator, and modulation amplifier stages. Transistor T1 (BF195) is… Read More »