Scott Harden writes: In an effort to resume previous work [A, B, C, D] on developing a crystal oven for radio frequency transmitter / receiver stabilization purposes, the first step for me was to create a device to accurately measure and log temperature. Check out the video after the break.
Category Archives: measurement
Yet another semiconductor V/I curve tracer – II
Kerry D. Wong posted an update on his semiconductor V/I curve tracer we covered previously: In my previous post, I showed my design of a semiconductor V/I curve tracer and discussed its theory of operation in detail. As promised, I will share some of the test results here. If you have not read my previous article, […]
OLED Backpack updates
Ed informs us that there have been a number of improvements on the OLED backpack from Fried Circuits! It’s turning into a fairly complete logging tool, now including multiscreen support (cycle between six screens with various readings), energy measurement (measuring charge in Wh and Ah), and interrupt-based reading. You can find details and updated information […]
Yet another semiconductor V/I curve tracer – I
Kerry D. Wong writes: Semiconductor curve tracers were frequently used in analog circuit designs many decades ago, at a time when discrete semiconductor devices were in dominance and ICs were scarce. While curve tracers are no longer widely used nowadays due to the ubiquity of digital circuitry and computer aided designs, they are still quite […]
FriedCircuits inline voltage/current tester board
Edouard gives us a preview of the new version of the in-line voltage/current tester board by FriedCircuits. He reports that the board is also compatible with the OLED Backpack (requires separate USB power source.) Via the contact form.
UPS transfer time measurement
Kerry D. Wong writes: Most offline/line interactive UPS‘ (Uninterrupted Power Supply) have a transfer time between 5 to 15 milliseconds. In this post, I will show you the results of the measured switch-over performance of my APC Back-UPS XS1500 and the technique I used.
USB Tester OLED backpack update
William at MobileWill posted an update on his USB Tester OLED backpack we covered previously: There is a new firmware update for the USB Tester OLED Backpack. This update completely redesigns the display and makes use of the button. You can find the update on github. If you need directions on how to update: www.friedcircuits
Measuring microamps & milliamps at 3 MHz bandwidth
Paul over at Dorkbotpdx writes: Recently I needed to actually “see” a current waveform in the 100 uA to 5 mA range with at least a couple MHz bandwidth. This extremely expensive probe would have been perfect, but instead I built something similar for about $30 using the amazing Analog Devices AD8428 amplifier.
Avalanche pulse generator build using 2N3904
Kerry Wong documented his avalanche pulse generator build using 2N3904: The majority of avalanche pulse generators hobbyists built used 2N2369, the same transistor used in Jim Williams’ original experiment. One of the main benefits of using 2N2369 is that it can avalanche at a relatively low voltage (under 90V). But most general purpose NPN transistors […]
Turn a smart phone into a signal generator
Jacob Beningo has written an article detailing how to turn a smart phone into a signal generator: Signal generators are a handy thing to have around the lab. They are perfect for testing inputs on a new hardware design and verifying the behavior of a circuit before connecting all the pieces together. In recent years […]
Photodiode Gamma ray detector
Alan over at vk2zay.net posted an article describing how he designed and built his gamma ray detector using a photodiode: Gamma photons interacting with cheap photodiodes produce small current pulses which are easily amplified and allow detection of individual photon events. This offers the possibility of cheap, small and rugged radiation detectors of reasonable sensitivity. While not […]
ATTINY2313 Thermometer width DS18S20
Thermometer width DS18S20: In my new Dacia Duster is missing unfortunately an outside temperature indication. A finished thermometer with LCD did not separate from there while the contrast with sunlight usually particularly is. I had still alphanummeric LED display in red there for this project in the best way am suitable. As microcontroller i used […]
400kHz function generator with ICL8038
Manekinen posted an article describing how he designed and built his 400KHz function generator based on ICL8038: Function generator with adjustable frequency from 0 Hz to over 400 kHz, adjustable amplitude, DC offset, duty, and of course the function selection – square, triangle, and sine. Generator based on good old ICL8038 integrated chip generator that […]
Tinkerer’s tricorder update
Nickjohnson posted an update to his network analyzer we covered previously: More tweaks and improvements! I’ve moved to a dedicated LED dimming controller for the backlight instead of resistors, and made a few other layout tweaks. It’s now out for fab. A friend put together some nice renders of the case for me Via the […]
Tinkerer’s tricorder
Nickjohnson wrote previously about his Loki PSoC based development board. Now he’s experimenting with the idea of building an ESR meter: I’ve been experimenting with different measurement options using the Loki as a test platform. I’m just about ready to start speccing out and designing a PCB soon, and I’ve got a nice case lined […]
Simple DIY ECG + pulse oximeter (V2)
Scott Harden has designed an ECG/pulse oximeter combo project using LM324 op-amps. Scott describes, “This new project is fully documented and uses extremely common and cheap parts, all of which could be purchased at RadioShack. It serves as both an ECG *and* a pulse oximeter, depending on which leads are attached. It uses a single […]
XR2206 function generator
“Presented here is XR2206 function generator with multiple waveform selection and a frequency readout display. The diagram on the right shows the internal workings of the XR2206 in the form of a block diagram. Essentially the chip contains A VCO (voltage controller oscillator), wave shaper and buffer. The XR2206 frequency generator diagram frequency of the […]
Bartendro serves up cocktails using open source
Bartendro is a robotic cocktail dispensing machine controlled by a Raspberry Pi. Dispensing of drink components is via peristaltic pumps which dispense a known volume with every revolution of the motor to precisely meter drinks. The Party Robotics developers explain, “Each pump combined with our custom electronics is called a “dispenser.” The dispenser boards use […]
1Hz to 10MHz frequency meter using ATtiny2313
1Hz to 10MHz frequency meter using ATtiny2313: This AVR-based Frequency Meter is capable of measuring frequencies from 1Hz to 10MHz with 1 Hz resolution. The hardware of this project consists of seven 7-segment displays, AVR ATtiny2313 uController, and a few transistors and resistors. The AVR counts input pulses for a precise 1 second interval (generated […]
Tiny breakout board for 24LC512 EEPROM and MCP9802 temp sensor
Raj I recently designed this tiny breakout board for Microchip’s 24LC512 EEPROM and MCP9802 temperature sensor devices, both of which support I2C protocol. This single board can be used for both sensing the ambient temperature and storing it. You can view the circuit diagram and get more details on Raj’s Tindie project at EmbeddedLab. Via […]