Mastro Gippo writes:
I just finished wrapping up an article about a small project I did in Shenzhen during the HackerCamp with Ian. I hope you find it interesting and feature it!
Making stuff in Shenzhen – The Grillino – [Link]
by Roy McCammon:
The traditional three op-amp differential amplifier’s signal to noise ratio can be improved by 6dB by adding a resistor and slightly changing the connections. There is a trade-off though: The traditional topology has a high input impedance, whereas the low-noise version has a lower input impedance.
Differential amp has 6dB lower noise, twice the bandwidth – [Link]
Ioannis Kedros writes:
Another quick project for today! How all started? A few hours ago I took a delivery box with few high resolution LCD’s on it. The box was made of foam material and was covered with dirty (from the delivery across two continents) yellowish tape.
To begin with, in order to open the box I had to remove half of this tape and by “playing” with the box I manage to remove everything without to damage it! Yes, the tape was strong enough to tear apart everything! The result is the one below
Rescuing a foam box – [Link]
By Tessel Renzenbrink:
David Hunt built himself a working mobile phone using a Raspberry Pi and off-the-shelf components. The main building parts are the $35 Adafruit Touchscreen interface and a $48 SIM900 GSM/GPRS module for making phone calls. In total the phone costs $158 to build.
PiPhone: Turning Your Pi into a Phone – [Link]
MotherBone™PiOne™ is a peripheral motherboard for BeagleBone Black & Raspberry Pi providing safe I/O expansion for Linux based systems
We were evaluating BeagleBone Black and Raspberry Pi for low cost control systems when we discovered that the modules, as shipped, were fundamentally unusable for anything other than connecting to your PC and programming.
We created a multi-tool: an all-in-one 3.5″ peripheral voltage isolating motherboard for the BeagleBone Black and Raspberry Pi Model B computers and expanded out and isolated all of the default configuration pins that were not being used by BeagleBone Black internal resources. We also created two different on-board communication links between Raspberry Pi and BeagleBone Black for advanced control functions. Now you are able to run both modules individually or simultaneously in the real world.
MotherBone PiOne on Kickstarter – [Link]
by Francesc Casanellas:
This design was done to get a sealed keypad for very wet environments (in my particular case, showers for swimming pools). The keypad needed to be able to detect slight pressure on a stainless steel plate 0.4mm thick. Apart from water protection, the solution offers an esthetical finish, as the user side is absolutely flat, with nothing visible other than the silkscreened print. Another advantage of this type of keypad is that it is vandal-proof. The core of the sensor is a piezoelectric disc, the type normally used as a buzzer. I chose the Murata 7BB-35-3. With 35mm of external diameter, it allows a sensitive area of about 20mm diameter.
Water & vandal-proof keypad uses piezoelectric disc as sensor and buzzer – [Link]
Raspberry Pi has been very popular small computer board. It’s initial layout is quite flexible that allows it to use as standalone computer or embedded device with controllable I/Os. Probably standard Raspberry Pi is more oriented to be small single board computer, where you can connect peripherals like keyboard, mouse, display, Ethernet. The I/O part seemed to be left on a side. Eventually extension boards started to appear to fill the need of functionality like ADC, DAC, more digital I/Os. Eventually you end up stacking stuff on top like Arduino. But we like elegant things don’t we? So Raspberry Pi team has been working on different Raspberry Pi concept – Compute module. This is smaller module which have same BCM2835 processor, same RAM. Instead of SD flash there is a 4Gbyte flash memory. Practically this is it. Module is traced on DDR2 SODIMM sized PCB which actually fits this connector.
Raspberry Pi Compute module – [Link]
nevdull @ instructables.com writes:
Tactile switches (a specific type of momentary switch) are everywhere and they are especially popular on DIY electronics and microcontroller boards because they are well suited to act as a boot option or reset switch. Particularly, momentary switches are switches that don’t save their state when you depress the switch. That is, when you push the switch (and while you have the switch depressed) the circuit is ON, but once you let off the switch it reverts back to OFF.
Use a Momentary or Tactile Switch as a Pushbutton Switch – [Link]
Home automation is the residential extension of building automation. It is automation of the home, housework or household activity. Home automation may include centralized control of lighting, HVAC (heating, ventilation and air conditioning), appliances, security locks of gates and doors and other systems. This provides better convenience, comfort, energy efficiency and security. Home automation for the elderly and disabled can provide better quality of life for persons who might otherwise require caregivers or institutional care. Nowadays, semiconductor companies develop IC that integrates the system as a whole. One of which is NXP Semiconductors which they develop Home automation modem IC TDA5051A.
The TDA5051A is a modem IC, specifically dedicated to ASK transmission by means of the home power supply network, at 600 baud or 1200 baud data rate. Its single chip power line modem is equipped with protection of its output power stage and AGC (Automatic Gain Control) of input signal. With simple coupling network, this power line modem is compliance with EN50065-1 power line communication standard. This power line modem circuit uses ASK (Amplitude Shift Keying) for the modulation, and operates on 5V supply.
A home automation system integrates electrical devices in a house with each other. Devices may be connected through a computer network to allow control and may allow remote access from the Internet. Through the integration of information technologies with the home environment, systems and appliances are able to communicate in an integrated manner, which results in convenience, energy efficiency, and safety benefits.
- TDA5051AT modem IC
- Schottky Diode
- 68Ω Resistor
- 2.2MΩ Resistor
- 7.3728Mhz Oscillator Clocks
- T 630mA Fuse
- General Diode (2 units)
- 2uF Capacitor
- 47 nF/X2 Capacitor (3 units)
- 470 µF Capacitor
- 100 µF Capacitor
- 1 uF Capacitor
- 10 nF Capacitor
- 5 µF Capacitor (2 units)
- 1 mH Inductor
- 47 µH Inductor (2 units)
- 1N4006 Diode
- 250 Supply Vac
- Positive Voltage Regulator
Power Line Modem for home Automation – [Link]