Stepper motor driver TB6600

For controlling stepper motors you need a suitable controller. It is possible to build controller using discrete components, controller ICs and using micro-controller. It can be fun to build our own stepper controller, but when you have done that few times, you might want to start looking or reasonably priced ready made easy to use

Bad CEM SMD-100

I got a CEM SMD-100 Smart Electronic Components Tester because it was on sale at very low price. It turned out to be a bad investment. The component tweezers part make very intermittent contact with the meter, so measuring the components was very unreliable. The meter seemed to work OK with the measurement supplied leads

Cheap poor HDMI to USB converter

Here is a story of one cheap HDMI digitizing device. I have wanted to connect devices with HDMI output Open Broadcast Studio video mixer/streaming software running on PC. Usually HDMI to USB adapters are expensive boxes (around $100 or more). But the I saw this really cheap (€16,15 / US$ 18.99) Mini Portable HD USB

PoE powered device PSU

With PoE (Power over Ethernet) technology, an Ethernet cable can carry power in addition to data. PoE can supply operating voltage to PoE compatible networked devices, such as a WLAN base station, an IP camera, a VOIP phone or IoT device. The original IEEE 802.3af-2003 PoE standard provides up to 15.4 W of DC power

Cheap eBay LED tester fixed

Found this from eBay for about 2 dollars: New Mini Handy 2~150mA LED Tester Test Box for Light-emitting Diode Bulb Lamp Description: 100% brand new and high quality Material: Plastic Color: White Handy device for testing LED’s. Simply plug your LED into the correct holes (all of which are marked) and push the button to

FrostBite IoT dev board

Sundelin & Kouri Engineering Ltd launched a completely new C++-based platform and development board for accelerated IoT and embedded development called FrostBite. The new board, Frostbite, is based on Nordic’s nRF52840 SoC silicon, featuring powerful 64MHz ARM Cortex M4F CPU, 256K of RAM and 1M of on-chip flash memory, on-chip soft radio for multitude of

PoE tester teardown

Here is teardown of one cheap power over Ethernet tester from eBay. It worked OK and did what it promised. It came with instructions that seem to be for a slightly different model witg more features. What is inside Circuit details. It has two sensing circuits: for end span and middle span power. I have

Arduino black ABS case

There are many different cases for Arduino.  Black ABS Protective Case For Arduino UNO R3 is an interesting plastic case for Arduino. The interesting feature in it is that it is designed to be compatible with LEGO blocks. It means that the case can be easily used in LEGO building projects. This is a reasonably

Transistor tester M12864 advanced version

I have earlier tested basic DIY Electronics Tester Kit M168 and more advanced Component tester M12864. Now it is time to test the next improved version of the same idea: Original Hiland DIY M12864 Graphics Version LCR ESR PWM Transistor Tester Kit (was on sale for less than 10 Euros) This kit has same display

Arduino UNO transparent case

I wanted to have a protective case for Arduino. I got this cheap (less than $2) Transparent Acrylic Shell Box For Arduino UNO R3 Module Board. Everything was packages to this small plastic bag. After installing eight screws and protective films from the plastic parts, everything was ready. I must admit that it takes some