Category Archives: Projects


A very simple DIY solar-powered USB charger

Yesterday, I built a very simple DIY solar-powered USB charger for my TP-link 10400mAh USB Power Bank. All I needed was a 6V/3.5W solar panel and the TD1410-based 5V buck converter module. I bought both of them on Aliexpress for less than $8. It was one of the easiest projects I built. All I needed to do was to connect the input of the 5V step-down buck converter to the output of the solar panel using two wires. From TD1410 datasheet, The TD1410 is a 380 KHz fixed frequency monolithic step down switch mode regulator with a built in internal Power MOSFET. It achieves 2A continuous output current

Read more

Making a simple ESP8266-based clock synchronized to NIST server

Internet has made it quite easy for computers to synchronize their clocks to an accurate clock value generated by a remote server. In the United States, the National Institute of Standards and Technology (NIST) provides official time. NIST disseminates the time using several methods, which include broadcasting over short-wave and long-wave radio, telephone dial-in services (ACTS), and Network Time Service (NTS) over the internet. This article describes a ESP8266-based clock project that utilizes NIST’s NTS service to retrieve accurate time information and display it on a 4-digit seven segment LED display. The time is synchronized to the NIST server after

Read more

Programmable relay switch using PIC MCU (revised version)

Programmable relays are key elements in numerous automation applications such as automatic street light control, watering and pump control, HVAC, home automation, power plants automation in industries, etc. This article describes a DIY programmable relay switch using PIC16F1847 (PIC16F628A can also be used) microcontroller. It is a revised version of my previous PIC-based relay timer project with added features and some improvements in the circuit design part. Like my previous version, it also allows you to set both ON and OFF times. The maximum time interval that you can set for ON and OFF operations is 99 hours and 59 minutes. The new version features

Read more

Development board for PIC16F1938

The PIC16F1938 is a versatile 28-pin MCU belonging to Microchip’s extreme low power microcontroller family featuring nanoWatt XLP technology, 28KB of programming memory, 1KB of RAM, 11 ADC channels, and tons of other peripherals. A while ago, I designed a development board for this MCU and I thought it would be worth sharing this design here. The development board features an onboard USB-UART bridge to support the ds30 Loader for easy programming of the PIC MCU. All I/O pins are accessible through 2×5 headers. Summary of Features: On-board 5V and 3.3V regulators Support both 5V and 3.3V MCUs. The power

Read more

Wireless communication between two Arduinos using inexpensive RF modules

This article explores an easy wireless communication setup between two Arduinos using low-cost ASK RF transmitter and receiver modules that are readily available in the market. They are found in different shapes, but functionally they are all same. Both Tx and Rx modules contain a single data line for input and output and support a low-speed Amplitude Shift Keying modulation for data communication. You can get them with 315MHz or 433MHz carrier frequency. In this tutorial, I am using a 433MHz Tx/Rx pair with two Arduino boards to illustrate how to construct a low-range wireless temperature and humidity monitor.

Read more
Recent Entries »