by Mark “hiddensoul” Clohesy @ hamshack.org:
I was looking at a low cost way to build a 10Mhz frequency for my electronics lab. I had a few options that I could pursue, these were…
GPS Disciplined Crystal Oscillator (GPSDO)
Rubidium atomic standard (RbXO)
Caesium atomic Standard
Oven Controlled Crystal Oscillator (OCXO)
So to make a choice on what I should use I had to come up with design parameters for my frequency standard, these were as follows.
Had to be low cost
Had to be portable
Had to work inside of a building
Had to be stable, better then +/- 0.5 hertz drift over 2 minutes
Low Cost 10Mhz Frequency Reference - [Link]
Charles Edward Pax has announced that the T400 temperature datalogger is now being offered on Kickstarter!
The Pax Instruments T400 datalogger is an open source four-channel thermocouple temperature datalogger based on the Arduino™ Leonardo platform. It is ready to use out of the box with the features you want most. Measurements can be logged to MicoSD card, printed to serial port, and graphed. The T400 is a great tool for anything from live thermal process monitoring in the lab to long-term environmental data collection in the field.
Data logger handles four thermocouples - [Link]
What could you make with a key fob containing a Bluetooth (BCM20737S) Smart chip, gyroscope, accelerometer, compass, barometer and humidity/temperature sensors? Broadcom are hoping their WICED (pronounced wicked) Sense kit will make an ideal development platform for engineers and developers working on the next generation of IoT applications. Together with the hardware Broadcom have an integrated Software Development Kit (SDK) using the WICED Smart SDK v2.1 and a downloadable WICED Sense app from the Apple App store or from Google Play for Android devices to allow interaction with the fob via a smartphone or tablet etc.
Something Wicked this Way Comes - [Link]
Who says logic analyzers canʼt be beautiful? Saleaeʼs Logic USB Logic Analyzer packs a lot of punch in a small, anodized aluminum package.
- Monitors up to 8 channels
- Saves up to 10 billion samples
- Is multi-platform Windows, Mac or Linux
- Can export data in binary, VCD and CSV
- Supports I2C, Async Serial, SPI, 1-Wire, CAN, I2S, PCM, and UNI/O
Used by students, engineers and hobbyists, Saleaeʼs analyzers have been used for satellites, avionics, submarines, electric cars, and more.
And with the launch of the Saleae Logic 4, 8, Pro 8 and Pro 16 next month, recording, measuring, and annotating will be even easier.
Saleae Launches New Logic 4, 8, Pro 8, and Pro 16 Analyzers - [Link]
A Geiger counter, also called a Geiger-Muller (GM) counter, is a type of particle detector that measures ionizing radiation. It detects the emission of nuclear radiation: alpha particles, beta particles, and gamma rays by the ionization produced in a low-pressure gas in a Geiger-Muller (GM) tube, which gives its name to the instrument.
A High Voltage generator (U1, U2, Q1, T1, and associated components) powers a GM tube. A pulse from the GM tube is interfaced through Q2 and U1 to pulse-generator U3, which drives a speaker.
Geiger Counter - [Link]
This DIY digital clock plus thermometer is designed by Joe Farr and is based on PIC18F25K22 microcontroller. The complete construction details of this project including circuit diagrams, PCB layouts and PIC firmware are posted in his website. He developed his firmware using Proton PIC BASIC compiler, which is available for download for free for this particular PIC microcontroller. He uses DS1302 RTC for timekeeping and DS18B20 for temperature measurement. The temperature and time are displayed on four 2″ seven segment LED displays.
Another PIC-based digital thermometer and clock - [Link]
Inspired from one of Dave Jones EEVBlog videos on dummy load, Lee has built his own programmable constant current resistive load that allows you to draw a set current from any power supply source. His design is based on Arduino Leonardo and uses the high-power BUK954R8-60E MOSFET to control the amount of current flowing through the load path.
Constant current resistive load controlled by Arduino – [Link]
herpderp shares his waveform generator:
Here is my last project, a tiny waveform generator based on my previous project and some components:
– An AD9834 (DDS chip with sinus/triangle output)
– 2 x AD5310 (10bit DAC: one for the Vpp control, another one the offset control)
– 3 x LM7171 (Fast OPA)
– 3 x LT1616 (switching regulator: +5V, +7V, -7V)
This waveform generator is directly powered by a standard 12V jack and is capable of outputting a 10Vpp signal at 1MHz (between -5V and +5V, sinus waveform, no load). Above 1MHz, the output starts fading, reaching only 9Vpp at 4MHz (maximal frequency). Frequency, amplitude and offset are digitally controlled through the smart TFT.
Three “basic” waveforms are provided: sinus and triangle, coming from the DDS chip (0.1Hz to 4MHz, 0.1Hz step), and PWM coming from the microcontroller (0.1Hz to 1MHz, variable steps).
Tiny waveform generator - [Link]
by BasinStreetDesign @ instructables.com:
I had a bunch of random inductors in some random drawers and I wanted to know what values they were. These values are quite often not obvious by looking at the device. Colour codes for old ones were not standardized and some of the coloured rings on inductors can be faded or discoloured so that its impossible to tell what they are. Others may be unmarked and any that are hand-wound are just guess work without a meter. So I decided to make an inductance and capacitance meter which would be fairly accurate and work over several decades of value from a few nano-Henries to a few milli-Henries and also from a few pico-farads to about a micro-farad (hopefully). Sounded easy – what could go wrong?
Inductance/Capacitance Meter Saga - [Link]
By Ben Coxworth @ gizmag.com:
Ever since the Fukushima nuclear reactor disaster, there has understandably been an upsurge in the sale of consumer radiation-detecting devices. Most of these gadgets are variations on the Geiger counter, in that they alert the user to the presence and level of radiation, but not the type of radiation – which is very important to know. Researchers at Oregon State University are hoping to address that situation, with the MiniSpec. Currently in development, the handheld device will additionally tell its users what type of radionuclide is creating the radiation, and whether it poses a risk.
Small, portable and cheap radiation detector is being designed for the public - [Link]