Kerry Wong writes: Transistors operating in their avalanche regions are often used to generate fast rise pulses (see avalanche pulse generator using 2N3904). Many transistors can also avalanche when the connections to collector and emitter are reversed. When operating in … Read more
Category Archives: testing
Kerry Wong writes: I was doing a project that needed a driver for hard disk spindle motors. While I could use a microcontroller to generate the required driving waveform sequence, keeping the waveform in sync with the motor rotation is … Read more
Bajdi did some tests for switch mode voltage regulators: There are different types of DC-DC regulators. The most common are linear and switch mode regulators. Everyone that has tinkered with electronics has probably used a 78xx series linear regulator. They are … Read more
mux writes: I’ve been doing some tests with the STM32F407 to see how fast it can go, STMicro has released an almost identical one that runs at 180MHz, is it a marketing thing ? will they release a 200MHz version … Read more
63 resistor reels just arrived for a test 0603 OOMP part book. Books and sheets should be here tomorrow. We’ll stuff some samples and get an idea of the time involved this weekend if everything goes smoothly.
Kevin Rye designed a simple LED tester: I decide to put together a small LED Tester board. It’ll be powered by a small coin cell battery. I can pick up an LED with a pair of tweezers and just simply … Read more
Baoshi writes: I bought some FT230X (FT230XS) USB-USART bridge chip recently for a new design. FT230X is not only cheaper than the traditional FT232RL, but also offers a new fancy “USB charger detection” function. This interests me because I’m quickly … Read more
Viktor wrote a post on his blog detailing his DIY test leads: The result is that now I have proper test leads with resistance of less than 0.1 ohm per meter. This is a measurement of one of my new test leads Also, … Read more
Kenneth Finnegan writes: As part of a few projects I’m working on, I want circuits to be able to decode DTMF tones played over an amateur radio link for remote control. This can be done with a moderately powerful processor … Read more
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.
An ATmega32 based Proteus simulation of 16 line connectivity tester by Dilshan Jayakody: The main functionality of this system is to detect open and short circuits in cables and connectors. This system can test maximum of 16 lines in each test … Read more
Debraj built an electrical dummy load to test his power supply and wrote a post on his site detailing it’s assembly: Recently, I purchased a power supply that claimed a max current of 2A and 0~15V. So I wanted to test … Read more
Alex over at InsideGadgets has posted an article describing how he built an ATtiny25 voltage controller oscillator (VCO): I recently bought a Rigol DS1052E and have been playing around with the different functionality it has. Eventually I came to the point … Read more
Here’s a simple adjustable current source with a PNP transistor that drives either one or two LEDs for testing and/or intensity matching purposes. The current is from 2 to 16 mA in four steps using a rotary switch. While this … Read more
Matseng continues his challenge of designing one PCB a week. His week 2 board, the DigiPot, has arrived and he assembled it. He did run into problems soldering the connectors which he unfortunately clustered under the encoder. Soldering them was … Read more
This week we received a batch of PCBs and amongst them was the latest revision of our USB TFT breakoutboard. This board is the first board that features a new ICSP footprint, which occupies less space on the PCB and … Read more
SJaak refers us to this article by Paul Stoffregen about how they test new Teensy 3.0 boards using a “testbed of nails.” Essentially the Teensy 3.0 crew has developed this testing interface which gives them a way to test every … Read more
To test his LCD launchpad booster packs, Robg improvised some DIY test connections. Using slightly larger than standard male headers and some rubber-bands, he is able to make solder-less contact between the Launchpad and his LCD booster pack. Via 43oh.
We all bought one of these USB microscope at the SEG Market. We were immediately fond of the heavy base and the smooth adjustment of the camera. We bargained a bit and bought it for 260 RMB ($40), that’s half … Read more
MicroCC is a constant current source, but focused on the low current microamp range. It uses the Touchstone Semiconductor TSM6025 voltage reference, a drop in replacement for the MAX3025 with better than 15PPM stability. The TSM6025 used both as the reference voltage and … Read more