1.6W Mono Audio Amplifier


1.6W Mono Audio Amplifier Project is based on TDA7231, which is class AB power amplifier with a wide range of supply.

  • Power supply: 5 To 12 VDC
  • Output: 1.6 W, 4 Ω / 1 W, 8 Ω
  • Low crossover distortion, soft clipping
  • PR1 Preset for Volume Adjust
  • Terminal pins for connecting power supply, input and output
  • Power On/OFF Switch
  • Power-On LED indicator
  • Four mounting holes of 3.2 mm each
  • PCB dimensions 36 mm x 52 mm

1.6W Mono Audio Amplifier – [Link]


Speech Recognition with Arduino and BitVoicer Server


leandro4b @ instructables.com shows us how to control some LED using your voice. He used an Arduino board and BitVoicer server to make this happen.

In this Instructable I am going to show how to use an Arduino board and BitVoicer Server to control a few LEDs with voice commands. I will be using the Arduino Micro in this Instructable, but you can use any Arduino board you have at hand.

Speech Recognition with Arduino and BitVoicer Server – [Link]

A DIY A4 Laser Engraver using ATmega328

Davide Gironi demonstrates his DIY A4 laser engraver made from a scanner and a printer using ATmega328:

This “Get Ready For Win98″ Laser Engraving Machine it’s built using an old scanner, and an old printer.
A laser engraving machine is a tool that uses lasers to engrave an object.

A DIY A4 Laser Engraver using ATmega328 – [Link]

Fake TV Security Light


RonM9 @ instructables.com has build a fake led TV security light based on Arduino and NeoPixel WS2812 LED ring.

Fast & Easy Fake-TV Light module built for under $5; with enhanced features. With the use of this device you can go on vacation leaving your home with a lived in appearance and thus an added layer of security. “I’m up and I am a night owl … or perhaps asleep on the coach in front of the TV, ready to be awakened.”

Fake TV Security Light – [Link]

Using Geophone Sensors to detect seismic events


JTAdams @ jtadams.ca has build an interface for his geophones using Raspberry Pi and managed to record some seismic events on this. He writes:

I have always been fascinated with how seismic detection can see what is under the ground. So much so, that I decided to try it for myself. It works by generating a wave from the surface and measuring the reflections bouncing back from the layers below use something similar to a microphone, called a geophone. I created some amplifiers to amplify the signals from the geophones, and read them with a raspberry PI. I will show how I did all this, and what the results were.

Using Geophone Sensors to detect seismic events – [Link]

Control accurate incremental voltage steps with a rotary encoder


by Anthony Smith @ edn.com:

Experimenting with an HF oscillator, I needed to control the varactor diode voltage in precise increments over a 2V-10V range. A buffered potentiometer was the obvious choice, and connecting two pots in series to give coarse/fine control (or using a multiturn pot) would offer improved control over the varactor voltage. However, this approach still didn’t allow me to generate uniform increments and decrements of the control voltage in a reliable, repeatable manner.

Control accurate incremental voltage steps with a rotary encoder – [Link]

CAN Transceiver for Automotive

The TJA1042 of NXP Semiconductor is a CAN transceiver with high-speed capabilities that provides a physical link between physical transmission medium and the protocol controller. The transceiver is designed for high-speed (up to 1Mbps) CAN applications in the automotive industry, providing the differential transmit and receive capability to a microcontroller with a CAN protocol controller.

The NXP high-speed CAN transceivers provide the interface between a Controller Area Network (CAN) protocol controller and the physical two-wire CAN bus. This ensures full interoperability with other ISO11898 compliant transceiver products. These transceivers offer a significantly improved ESD robustness, a further reduction in Electromagnetic Emission (EME), an improved Electromagnetic Immunity (EMI), a higher voltage robustness in order to fully support 24V applications, and a predictable undervoltage behavior at all supply conditions.

The circuit shows how to integrate the TJA1042T within a typical application. The application example assumes either a 5V or a 3V supplied host microcontroller. There is a dedicated 5V regulator supplying the TJA1042T transceiver on its VCC supply pin (necessary for proper CAN transmit capability).

CAN Transceiver for Automotive – [Link]


C.H.I.P. vs Pi Zero: Which Sub-$10 Computer Is Better?


David Scheltema @ makezine.com compares the C.H.I.P computer with Pi Zero to find our which is the best option for your next project:

Now that there are two capable, sub-$10 computers for Makers — the $5 Pi Zero and the $9 C.H.I.P. — the debate will rage online over which board is faster, cheaper, and the right one to use in a project. These debates are often unproductive, but they don’t have to be. Let’s take a look at some of the pros and cons of each board.

C.H.I.P. vs Pi Zero: Which Sub-$10 Computer Is Better? – [Link]

Solar powered Particle Photon environment monitor


FutureSharks @ github.com has another great project on it’s repository, it’s a solar powered particle photon enviroment monitor.

Here is the Photon code and hardware details to build a solar powered environment monitor. It uses a combo module of 3 separate sensors that are read via I2C protocol to periodically measure and record:

Light level
Air pressure
Battery charge

Solar powered Particle Photon environment monitor – [Link]


HiFi Passive Preamp


FutureSharks @ github.com has build a very nice HiFi passive preamplifier controlled by an Arduino board.

It has the following features:

  • Volume control and input selection via encoder and Apple remote.
  • Uses a 256 step R2R relayed based attenuator.
  • Completely passive.
  • Only 5V power required.
  • Adafruit NeoPixel shows volume level with colour.
  • Sleep mode with low power consumption: 0.9W.

HiFi Passive Preamp – [Link]