Inside the SDS7012 Oscilloscope: Mainboard Analysis


Christer Weinigel has been tinkering with an OWON SDS7012 o’scope, including deciphering the device’s OS and even disassembling the bootloader. Now it’s time to dive in and examine the mainboard, physically, with many of the board’s sub-circuits explained. via

Except for soldering some wires to the JTAG and serial port on the scope, most of the things I have discoveries about the SDS7102 I have made so far has been done with just software and a bit of thinking.

Inside the SDS7012 Oscilloscope: Mainboard Analysis – [Link]

Wireless Weather Station using Arduino Due, DHT22 sensor and NRF24L01+ uploaded a new project on youtube.

In this video we build a Wireless Weather Station using the fast and powerful 32bit Arduino Due board. We measure the temperature and the humidity with a couple of DHT22 sensors and we communicate with the remote sensor using the 2.4GHz NRF24L01+ module. Let’s see how to build this project!

Today’s project is this. A Wireless Weather Station with a big 3.2” Color TFT display. As you can see, the project is up and running, and it displays the current date and time, the indoor temperature and humidity, and the outdoor temperature and humidity. The readings of the outdoor sensor are updated every second in order to demonstrate that we have a reliable communication link established with the transmitter which is outside at a distance of 5m. The readings of the indoor sensor are updated once every minute. The heart of the project is the fast Arduino Due, and as you can see there is no flickering of the screen when the values are updated. Let’s now see the transmitter.

The transmitter is much simpler. It consists of an Arduino Nano, a DHT22 sensor and the NRF24L01 wireless transceiver module. The transmitter reads the temperature and the humidity every second, and sends them to the receiver via the NRF24L01 module. This is a one way communication link, we don’t know if the receiver actually receives the data, but we send new data every second, so in case we miss a package we are going to receive another one soon. Let’s now see how to build this project.

Wireless Weather Station using Arduino Due, DHT22 sensor and NRF24L01+ – [Link]

Count down timer for UV lamps using PIC16F887


Here is a countdown timer for UV exposure lamps @

Here follows a simple count down timer useful for the production of pcbs using photoresist and UV lamps. We have used a pic 16F887 Microchip microcontroller; there are no particular reasons, we have simply used the picmicros available at the moment.

Count down timer for UV lamps using PIC16F887 – [Link]

High Current Discrete Half-Bridge Based on IR2104 or IR2101


This is a discrete Half-bridge driver based on IR2104 gate driver IC and low impedance high current N channel IRFP4368 MOSFETS. The IR2104 is a high voltage, high speed power MOSFET driver with independent high and low side referenced output channels. HVIC and latch immune CMOS technologies enable ruggedized monolithic construction. The logic input is compatible with standard COMOS or LSTTL output, down to 3.3V logic. A gate IR2104 driver is a power amplifier that accepts a low-power input from a controller IC and produces a high-current drive input for the gate of a high-power transistor such as a power MOSFET. In essence, a gate driver consists of a level shifter in combination with an amplifier.

This drive has many application, ranging from DC-DC power supply for high power density and efficiency, This project simplifies the design of control systems for a wide range of motor applications such as home appliances, industrial drives, DC brushed motors , Brushless motors, fans, Tesla Coil driver, Induction coil driver, LED driver, Halogen Lamp driver.

High Current Discrete Half-Bridge Based on IR2104 or IR2101 – [Link]

Dynamic-load circuit determines a battery’s internal resistance


by @

The simplest model of a battery comprises an ideal voltage source that connects in series with a resistance whose value—often a few milliohms—depends on the battery’s electrochemical condition and construction. If you attempt to use an ordinary ac milliohmmeter containing a kilohertz-range ac excitation source to measure a battery’s internal resistance, you get erroneous results due to capacitive effects, which introduce losses. A more realistic battery model includes a resistive divider that a capacitor partially shunts (Figure 1). In addition, a battery’s no-load internal resistances may differ significantly from their values under a full load. Thus, for greatest accuracy, you must measure internal resistance under full load at or near dc.

Dynamic-load circuit determines a battery’s internal resistance – [Link]

16 Channel InfraRed remote controller


16 Channel Infra-Red remote controller is based on PIC16F73 Microcontroller from Microchip. The receiver part follows RC5 (Philips) Code Format. Tiny receiver provides 16 latch outputs or 8 Latch + 8 Momentary outputs by closing Jumper J1. All outputs are TTL and can drive Relay board or solid state relay. The circuit uses TSOP1738 Infra-Red receiver module which provides high degree of noise immunity against interfering light source.


  • Supply Remote Transmitter RC5 Philips 2XAAA Battery
  • Supply Receiver 7V to 12V DC
  • Modulation 38Khz
  • Philips RC5 Code Format
  • Operating range up to 20 feet
  • 2 Pin Screw Terminals for Supply Input
  • On Board Power LED
  • Onboard VT (Valid Transmission) LED
  • All Outputs TTL Level provided with Header Connector
  • Jumper (J1) for Mode Selection
  • J1 Open 16 Latch Outputs
  • J1 Closed 8Latch + 8 Momentary

16 Channel InfraRed remote controller – [Link]

Consolite – a Tiny Game Console on an FPGA


Robert Fotino has design a video game system on a FPGA. He writes:

For my latest project, I am diving back into Verilog to create the hardware side of Consolite. For those who don’t know, Consolite is the name I’ve given to my design of a tiny hobbyist game console and associated software toolchain. In my previous posts, I demoed a compiler that translates from a flavor of C to Consolite Assembly, an assembler that translates from Consolite Assembly to binary files, and an emulator that runs the resulting binaries.

Consolite – a Tiny Game Console on an FPGA – [Link]

Butchered USB TTL Serial Adaptor


Aaron Brady writes:

We popped open the case, and there were two main ICs, a Prolific 2303 (the USB to Serial IC) and a ADM3251E (the RS232 line level convertor). I tried to desolder this with no success, but Bas stepped in, cut the leads with a craft knife and ran the iron over the chip’s leads and it basically fell off. He also did the very fine soldering to pins 1 and 5 of the Prolific chip, TX and RX respectively.

Butchered USB TTL Serial Adaptor – [Link]

Learn how to play sound with Arduino by building a DIY Micro Piano

In this video we are going to learn how to make sound with Arduino. We are going to build a simple Micro Piano in order to demonstrate the capabilities of the tone function. Let’s start!

Playing back sound is great for adding audio feedback to our projects. So far we were using displays or LEDs in order to provide feedback to the user of the project. Today we will learn how to make sound with Arduino and as you are going to find out, it is very easy.

In order to demonstrate the sound capabilities of the Arduino Uno, I have built a simple project, a micro Piano. Each time I press a button, Arduino makes a sound of a specific frequency for each button. The frequencies correspond to specific music notes, we have 7 buttons, so we can have 7 notes! So, let’s try it. I am going to play a simple song using the available notes.

Learn how to play sound with Arduino by building a DIY Micro Piano – [Link]


WiFiRGB – A WiFi-enabled RGB high-power LED


Tom blogged about his WiFi/Browser controlled RGB LED project:


Simple hardware, using pre-fabricated modules

Controls an RGB LED via any recent browser, any operating system

WiFi credentials can be configured via browser

Software is written as an Arduino sketch

WiFiRGB – A WiFi-enabled RGB high-power LED – [Link]