PhotosUpdate: 24 June 2012One of my colleagues in a Bulgarian audio forum ask me to build him a copy of the LC meter, but this time with 9V battery power supply. The device is very sensitive – when I put the test leads there is 3-5 pF reading on display, but it is eliminated with the calibrating button. In the first of them, there is 1nF/1% capacitor and in the second – 22uH/10% inductor. Total consumption (with back light) of the device is 30mA.R11 limits the back light current and must be calculated according to the actual LCD module used.I used the original PCB as a starting point and modified it to suit better to my components.Here is the result:The last two pictures shows LC meter in action. Two 1000pF capacitors are styroflex 1% and inductor is 82uH.

Following the above link you will find the original schematic, PCB, source and HEX files for programing the microcontroller and detailed description.Here is my adaptation of the schematic:I removed the 7805 regulator, because I decided to use a 5V adapter from Sony mobile phone.In the schematic, trimmer-potentiometer is 5k, but actually I put 10k, after consulting with the datasheet of the LCD module I bought.Īll three 10uF capacitors are tantalum and C7 – 100uF actually is 1000uF. This type of meter, especially L meter is hard to find in cheap commercial multimeters.Schematic of this one came from this web page.It uses PIC microcontroller 16F628A, and because I recently acquired a PIC programmer, I decided to test it with this project. DescriptionHere is another piece of laboratory equipment – LC meter. This project is a simple LC meter based on PIC16F682A mcu. 16f628a Simple Program Design Chapter 9.

16f628a simple program