This is a 8 channel relay interface board using ULN2803. All the relays are opto-isolated using optocouplers and can be controlled directly using a microcontroller of any kind (Arduino , 8051, AVR, PIC, DSP, ARM, MSP430, TTL logic) or a PC.
It’s easy to manufacture and have three pin screw terminals for easy connectivity.
8 Opto-isolated Relay board - [Link]
This Photodiode based Alarm can be used to give a warning alarm when someone passes through a protected area. The circuit is kept standby through a laser beam or IR beam focused on to the Photodiode. When the beam path breaks, alarm will be triggered. The circuit uses a PN Photodiode in the reverse bias mode to detect light intensity. In the presence of Laser / IR rays, the Photodiode conducts and provides base bias to T1.
The NPN transistor T1 conducts and takes the reset pin 4 of IC1 to ground potential. IC1 is wired as an Astable oscillator using the components R3, VR1 and C3. The Astable operates only when its reset pin becomes high. When the Laser / IR beam breaks, current through the Photodiode ceases and T1 turns off. The collector voltage of T1 then goes high and enables IC1. The output pulses from IC1 drives the speaker and alarm tone will be generated.
A simple IR transmitter circuit is given which uses Continuous IR rays. The transmitter can emit IR rays up to 5 meters if the IR LEDs are enclosed in black tubes.
555 Photodiode alarm - [Link]
7-42VDC Input 5V 2A USB Output Power Supply. Compatible with Raspberry Pi, Arduino, iDevices, Mobile Phones and other USB Devices.
Having to use a Raspberry Pi and other USB Devices in an electronics production environment where 5V isn’t standard, I have noticed a lack of power supplies capable of fitting in. A unit had to be designed to fit into systems where 12V & 24V are the norm or where batteries / solar panels etc are the only supply method available.
7-42VDC to USB Supply/Charger - [Link]
lowpowerlab.com imported a laser cutter from China and discuss the process:
As a break from the pick and place posts, in this article I’d like to aggregate my research about laser cutters and my experience importing a chinese laser cutter. There’s a wealth of knowledge scattered around the web, and this article won’t meet everyone’s search criteria, but hopefully this will be a resourceful stop for those that are in the search for a similar machine on a budget that can achieve the same results as a high end laser cutter/engraver.
Importing a laser cutter from China - [Link]
CDC-232 creates a virtual COM port on PC that doesn’t have real RS- 232C port. It enables RS-232C communication (without control lines), after connecting the device and installing the driver.
Write the program to AVR, build the circuit, and connect the device to PC’s USB port. Install the driver on Windows. Access the device through generated virtual COM port from terminal software or your application. Control lines (DTR, DTS, RTS, CTS) are not used by the host application. Set the terminal software as “no flow-control”.
Windows requests the driver installation again when connected to other USB port. Detect the previously installed driver automatically. Another COM number will be assigned. If you set serial number in AVR (rebuild with modified usbconfig.h), you can get the same COM port at any USB port. However, you cannot connect multiple CDC devices of the same serial number.
Before detaching the device, close the COM port in terminal software or in your application. Otherwise, you cannot connect to the device again because of the broken file handle. Restart the terminal software or your application then. Switch to the fast transfer mode using “lowcdc.vbs” to get the baudrate higher than 9600bps.
CDC-232 – Virtual COM on ATMEL AVR - [Link]
EGYDuino is a DIY Arduino clone made on a single sided PCB board. It’s simple and cheap to build using home PCB fabrication methods and it’s 100% compatible with Arduino.
The features of this board are:
- It’s using ATmega8 as interface IC
- Has USB connection to PC
- Standard RESET button
- 100% compatible Arduino PINs
- 5V regulator
- 3.3V output
- compatible size and design
- All component are TH (through hole) parts
- USB or DC power switch
- LED for PIN13 with Jumper
- LED for power
- ICSP PINs
- easy to build
- ATmega8,168,328 core for arduinoNG
- standard DC power jack
EGYDuino – Arduino compatible board - [Link]
This project started out from a need build a simple device for monitoring the CAN bus. I chose the NUC140LC1CN 32K Cortex-M0 microprocessor from Nuvoton for major reason – it has both USB and CAN peripherals.
- Simple design
- Compatible with the LAWICEL CANUSB protocol
- Exposing itself as USB FTDI device
- Supporting CAN 2.0A 11-bit and CAN 2.0B 29-bit frames
- Has internal FIFO CAN message buffer
- Self powered from USB port
- Flash-resident USB mass-storage device (MSD) bootloader for firmware updates
- Firmware is available for download
CAN-USB Interface - [Link]
This is the portable version of the Xminilab. The Xminilab Portable is a small mixed signal oscilloscope with an arbitrary waveform generator and protocol sniffer.
- Mixed Signal Oscilloscope: Simultaneous sampling of analog and digital signals
- Advanced Trigger: Normal / Single / Auto, with rising or falling edge and adjustable trigger level
- Meter Mode: Average, Peak to peak and Frequency readout
- XY Mode: Plot Lissajous patterns, See the phase difference between two waveforms
- Spectrum Analyzer with different windowing options and selectable vertical log
- Horizontal and Vertical Cursors with automatic waveform measurements
- Arbitrary Waveform Generator with Sweep on all parameters
- Display options: Persistence, Different grid options, and more
- Curve tracer function
Xminilab Portable Small Mixed Signal Oscilloscope 2.42″ OLED - [Link]
by Dario Borghino:
Scientists at the Cockrell School of Engineering at the University of Texas have built and tested what appears to be the world’s smallest, fastest, and longest-running nanomotor yet – so small that it could fit inside a single cell. The advance could be used to power nanobots that would deliver specific drugs to individual living cells inside the human body.
In the distant future, when faced with a cancer diagnosis, we might be able to simply ingest a “magic pill” filled with hordes of miniscule nanobots that target individual cancerous cells with drugs and leave the healthy ones unharmed. To power those robots, we need a nanoscale-sized motor that’s capable, sufficiently long-lived, and flexible enough for a wide range of applications.
World’s smallest nanomotor could power cell-sized nanobots for drug delivery - [Link]
tiq – see what’s happening inside your Arduino, RasPi, robot or 3D printer – no settings, just probe & tiq tells you – automatically!
tiq is designed to be the first tool you’ll use when chasing issues in your electronic project, Arduino, Raspberry Pi, internet-of-things-thing or robot – automatically giving you fast, detailed information in an easy-to-connect handheld probe. No other tool has ever offered tiq’s unique combination of powerful features – or its low price!
Tiq Probe – an easy to use tool for debugging maker projects - [Link]