This simple  circuit is used to test  N-Mosfets and P-Mosfets transistors. Source: Smjesko (elektronika.ba)        Download: Mosfet Tester.rar

USB – RS232 converter, uses only Tx and Rx lines, with selectable 2400, 9600, or 38400bps. PCB projected to fit in old mobilephone cable, most of parts is surface-mounted. Source: diy.elektroda.eu Download Project: Converter USB – RS232

In this project Dilshan design an Inverter to convert 12V DC power source to 230V AC power. This system consist 3 main stages such as oscillator, switching circuit and step up transformer stage. In oscillator we use 4047 CMOS astable multivibrator to generate nearly 60Hz oscillation. Source:Dilshan Download: Complete schematic and PCB diagrams

This is a small frequency counter with a cheap PIC microcontroller and a few seven-segment LED digits. The main features of the frequency counter are: *   frequency range 1 Hz … 50 MHz (prototype worked up to 60 MHz but this exceeds the PIC’s timing specifications) * four or five digits resolution (display for example [...]

This is a simple capacitance meter which can measure capacitance value easy. There are some measurement methods for capacitance, at one time the capacitance was measured with a impedance bridge or a dip meter. Recently typical capacitance meters can measure capacitance and some additional characteristics from current vector by applying AC voltage to the Cx. [...]

In early 2005, NEC launched small pin count microcontrollers like PIC/AVR based on 78K0S architecture. The 78K architecture has a register set similar to i8085 and additional bit operation instructions. It can be saied that a stale architecture but the memory space is plain compared to PIC/AVR. There are various devices with application specific peripherals [...]

This is a simple circuit to connect your VGA graphics card to your TV. The advantage of using RGB over S-Video is superior contrast and clarity. The schematic of this circuit is taken from Tomi Engdahl’s site. The circuit basically XORs together your horizontal and vertical synchronization signals to create a composite sync output, and [...]

This is a simple circuit which can detect when you touch a sensor connected to one of the sensor inputs. It can be used to add a touch switch to your computer for example. It uses an AVR micro controller, the AT90S2313. Source: Pontus

Today I would like to present USBtiny programmer with USB interface. The heart of the system is ATtiny2313. Source:elektroda.pl Download:USBtiny programmer

Amplifier for Subwoofer with TDA2030. Source: elektroda.pl

This is simple thermometer with just few components. The brain is PIC16F84A and sensor is DS18B20. Range of sensor is -55 to 125°C is possible if ONLY the sensor is in that area not the whole device! Source: maco