Single Chip Temperature Data Logger
https://www.electronics-lab.com/project/single-chip-temperature-data-logger/
Introduction A data logger is a device that records measurements over time. The measurements could be any physical variable like temperature, pressure, voltage, humidity, etc. This project describes how to build a mini logger that records surrounding temperature values. It has following features: Uses just one 8?pin chip, so very compact size circuit. Temperature range: […]
Ultra High Sensitive Probe
https://www.electronics-lab.com/project/ultra-high-sensitive-probe/
Description This circuit is so sensitive it will detect “mains hum.” Simply move it across any wall and it will detect where the mains cable is located. It has a gain of about 200 x 200 x 200 = 6,000,000 and will also detect static electricity and the presence of your hand without any direct […]
Voltmeter + Ammeter LCD panel
https://www.electronics-lab.com/project/voltmeter-ammeter-lcd-panel/
Introduction This multimeter was designed to measure output voltage and current in a PSU, where the current sense shunt resistor is connected in series with load at the negative voltage rail. It needs only one supply voltage that can be acquired from main PSU. An additional function of the multimeter is that it can control […]
Simple Crystal Tester
https://www.electronics-lab.com/project/simple-crystal-tester/
Description Transistor Q1, a 2N3563, and its associated components form an oscillator circuit that will oscillate if, and only if, a good crystal is connected to the test clips. The output from the oscillator is then rectified by the 1N4148 signal diode and filtered by C3, a 100pF capacitor. The positive voltage developed across the […]
Transistor tester
https://www.electronics-lab.com/project/transistor-tester/
Description This is basically a high gain amplifier with feedback that causes the LED to flash at a rate determined by the 10u and 330k resistor. Remove one of the transistors and insert the unknown transistor. When it is NPN with the pins as shown in the photo, the LED will flash. To turn the […]
Logic Probe Plus
https://www.electronics-lab.com/project/logic-probe-plus/
This project is based on a probe logic states, capable of measuring levels from TTL (5v) to state levels of PLC’s (24v). For this we have employed the use of the PIC 12F683 microcontroller, which by its nature is capable of operating at low voltages, in this case 3vcc, besides having analog inputs and internal […]
Logic Probe
https://www.electronics-lab.com/project/logic-probe/
Description This circuit is a Logic Probe. It indicates the logic state of the node of any TTL logic circuit. To do that, we have to supply the probe with the same power of the circuit that we want to analyse: same Vcc and same GND. To check the logic level, we must connect the “Test” […]
Led display digital Voltmeter
https://www.electronics-lab.com/project/led-display-digital-voltmeter/
Copyright of this circuit belongs to Smart kit electronics. On this page, we will use this circuit to discuss improvements and we will introduce some changes based on the original schematic. General Description This is easy to build, but nevertheless very accurate and useful digital voltmeter. It has been designed as a panel meter and […]
Mosfet Tester
https://www.electronics-lab.com/project/mosfet-tester/
This is a variation on the astable multivibrator. Circuit was recently developed to test for N-mosfets (the power kind e.g irf830) I dont claim circuit can test all bad mosfets or all fault mosfet conditions. If mosfet is working it will operate in the astable multivibrator circuit causing the Led to flash. A bad […]
Phone Busy Indicator
https://www.electronics-lab.com/project/phone-busy-indicator/
Have you ever been using the modem or fax and someone else picks up the phone, breaking the connection? Well, this simple circuit should put an end to that. It signals that the phone is in use by lighting a red LED. When the phone is not in use, a green LED is lit. It […]