Circuit board business cards have been done. But since circuit boards are, literally, my business, I felt that I needed one too. Of course it also had to be special. Research and experimentation took a long time with this one and the design even sat dormant, ready, for a while before I sent it out to fab.
An engineer’s emergency kit business card - [Link]
zmashiah @ instructable shows us how he build a display to easily check for his phone status, like battery remaining charge, missed calls and unread SMS. Data is transfered to an Arduino board via bluetooth. He writes:
When at home, I do not carry my phone with me everywhere… so sometimes phone rings or an SMS comes in and I do not hear that. With the volume of music played by the teenagers at home, that is not a surprise so I decided to build a small accessory that will show up the number of missed calls and unread SMS. In order to ensure it is very visible I use a 7 Segment LED display so it can be viewed from distance.
Bluetooth mobile phone accessory for Missed calls and SMS - [Link]
Here is a very nice graph showing the most popular programming Languages of 2014.
Every year we release data on the “Most Popular Programming Languages” based on thousands of data points we’ve collected by processing over 100,000+ coding tests and challenges by over 2,000+ employers.
This gives us a pretty good idea on what the trends are for the upcoming year in terms of what companies are looking for. It’s data we hope will be especially helpful for new computer sciences graduates or coders looking to stay ahead of the curve.
Most Popular Programming Languages of 2014 - [Link]
GodsTale build an OLED wrist watch using Arduino Pro mini and a Bluetooth module. He writes:
Retro Watch is an open source project to let you make a smart watch based on Arduino and Android. This text explains about modules, blueprints, how to install and use the Arduino and the Android source codes step by step.
RetroWatch: A DIY Smartwatch using Arduino - [Link]
Ralph shared his auto-reset feature of his Arduino board. He writes:
Various versions of the Arduino will reset the board by toggling the serial DTR line, a feature called auto-reset. Since it relies on the DTR line, it won’t work with TTL serial adapters that don’t break out the DTR line. After writing my half-duplex serial UART, I thought of using the TTL serial break signal which holds the line at 0V for several ms. Normal serial communications would also send 0V, but at 57.6kbps, it would never last more than 160us before returning to the idle high voltage state. So what I needed was a circuit would not reset when the line is low for 160us, but would reset when the line is low for 100ms or more.
Zero-wire serial auto-reset for Arduino - [Link]
In this episode Shahriar continues his investigation of discrete Bipolar amplifier design. The advantages and disadvantages of Class-A amplifiers are explained. The conceptual schematic of a Class-B amplifier is presented which leads to the introduction of Class-AB amplifier circuit to overcome the ‘dead-zone’ impairment of a push-pull Class-B design. To further improve the Class-AB amplifier and lower its input impedance, a final Class-A followed by Class-AB amplifier is presented The component parameters are calculated and the schematics is explained in detail. All circuits are then implemented on a breadboard and tested both in the time domain and frequency domain. All schematics can be downloaded from The Signal Path website.
Tutorial on the Design and Characterization of Class-B and AB Amplifiers - [Link]
Why is it worth to use a push-button with a declared resistance to dust and water even in a common environment?
In case, that a device is used outdoor, it is usually a necessity. But how is it in the case, that a device will be operated indoor in a relatively “good” environment? Here it depends mainly on a designer´s choice, whether he´ll use a component with a higher protection class or not. Despite the fact, that to use a push button with a higher IP class usually means somewhat higher price, but it provides one big advantage – reliability.
We know, that even in an indoor environment, especially in a production halls or stocks it´s very often a higher dustiness and a remarkably fluctuating humidity. These are naturally conditions, which don´t flourish to contacts, thus a button or a switch with a higher protection class can mean a significant increasing of reliability.
In the nowadays „microprocessor“ age, it´s very often, that the control buttons switch only a minimal current. As a result, this small current isn´t able to act as self-cleaning for contacts and the switches fail prematurely. Even in these cases, it´s beneficial, when a push button is more resistant to dust and water.
Marquardt 5000.0501 is a literally universal push button, because it features an IP54 protection class from both sides. It´s able to switch 4(2)A/250V AC and a plus is also a high mechanical lifetime – up to 200.000 cycles. Relatively higher driving force and a sufficiently long travel (4mm) acts also as a protection against accidental operation.
Marquardt 5000 series push buttons won´t be scared of dust and water - [Link]
Exar have announced the 5 mm square SP335 transceiver chip which supports RS-232, RS-485 and RS-422 serial standards. It is a single chip solution between the serial comms port and the UART or MCU allowing system designers to cater for multiple serial protocols over the same connector. The transceiver’s programmable end-of-line termination and multiple configuration modes allow all three protocols to be used interchangeably over the same cabling and connector without the need for additional switching components.
Built in protection tolerates direct shorts to DC or AC voltages as high as ±18 V and severe ESD events. The chip features a separate supply voltage for the logic interface pins, which can be as low as 1.65 V. This allows direct interface with low voltage UARTs and MCUs without the need for level shifters. It also supports data rates up to 20 Mb/s in RS-485/422 modes and 1 Mb/s in RS-232 mode and can be slew limited to 250 kb/s toggling a single control pin. With no inductors or magnetic components, the on-board charge pump generates the RS-232 bipolar voltage levels from a single supply (3.0 to 5.5 V) using just four external capacitors. [via]
Transceiver Chip Handles RS-232, RS-485 and RS-422 - [Link]
Adapters with an attribute “medical” can help you to meet stringent requirements for this segment.
If you produce a device with a supposal to be used in a hospital or in a medical segment in general, it´s naturally necessary that it must meet more stringent requirements, given for example by a 93/42/EEC directive about medical devices.
High reliability and a high isolation (primary/ secondary winding) belong to basic requirements. Adapters Friwo – medical meet these and also many other requirements and they also gained many international attests. In the Friwo portfolio can be found a wide range of various medical adapters with power of 3-30W, „desktop“ adapters with power of 12-150W and also „open frame“ modules with power of 65-250W.
In our stock a universal type GPP18M (1890856, FW7556M) can be found, with a 12V/1500 mA output. It features a constant voltage with a current limitation and a protection against continuous shortcut. Now we offer you a GPP18 Medic set containing a power source, AC Euro inlet adapter and an output DC connector 5,5/2,5/11,5mm for an exceptional price.
Should you be interested in a relatively bigger amount of these adapter in a different version (other mains inlet adaptor or other DC connector), we´ll certainly find a solution. Detailed information will provide you the Friwo_medical overview.
Do you produce devices for medical segment? - [Link]
Here is a very nice build of a LED heart that creates incredible animations. Check it out.
Today we present the perfect Valentine gadget: just shake it and it will turn on and crate incredible light animations. That will be cool for sure!
We know that, as it’s Valentine’s Day, looking at the device described in this post you’ll be inclined to think that this is the usual heart-shaped Valentine gadget: in reality this is something much cooler as it’s capable to create beautiful and complex light games. Is based on the smallest microcontroller manufactured by Atmel: the ATtiny85.
Hack your Valentine with HeartThrob - [Link]