Tech tips electronics

Vacuum tubes are awkward, need always 6.3V filament and high supply voltage? No, they can also work on 3.3V. I have built a vacuum tube pre-amplifier that runs entirely on 3.3V, inclusive the ...

I have developed a cheap multimeter 0.02% precision reference by which you can calibrate a digital multimeter yourself. Here we calibrate my favorite multimeter, the PeakTech 2010, it has a lo...

USB-C as power connector tested on supporting 2000W USB-C connectors can support 100W, which is a lot for such a small connector. So, I wanted to investigate how that works. It would be funny to i...

When reverse engineering the electronics of a Wattmeter from AliExpress, I came across a remarkable Chinese switching DC-DC converter chip that I had never seen before: the FT8430. I want to b...

The MH-M38 is a stereo audio receiver with loudspeaker outputs which can play music from a smartphone wireless via Bluetooth. MH M38 Bluetooth audio receiver circuit redesigned Because I wanted t...

On the internet I came across a funny design: a discrete 741 operational amplifier. You can buy it at Adafruit, see the circuit also here: Adafruit XL741 discrete 741 opamp 741SE By the way, the...

I’m developing a fast battery charger and to check whether it meet the EMC limits for harmonic currents, I need to analyze the spectrum with FFT analysis. To do so, I had to find out how it works o...

Transistor SMD assortment sample book values overview Here are the main properties of the transistors in the assortment books with 36 values. The TL431 is a regulator. Nr Name ...

The electrolarynx is the most widely used device for speaking without vocal cords. However, its use is not very elegant, therefore I built a prototype of an electronic bluetooth larynx. The el...

Cheap mini power supplies Here, I want to tell a story about mini power supplies. Conventional power supplies, which use mains transformers, have the disadvantage that the product becomes heavy an...

A lightweight switching power supply of 2000W/kg The Panasonic microwave oven HV inverter is a remarkable design, because it is a half-bridge converter of 1000W with a low weight of just 470g. Tha...

My Arduino compatible SAMD21G board, the SAM 15x15, can be built into small drones. To demonstrate this, I made some photos of the Cheerson CX-10WD mini drone together with the SAM 15x15 board.&nbs...

Abstract The design of complex op-amp circuits often turns into a puzzle and the creation of many formulas. Therefore I describe here a straightforward method which makes this task easier.The ba...

Electrocution by microwave oven Microwave oven repair safety precautions What is more dangerous, the overhead line of a train or the inside of your microwave oven? It is the microwave oven, bec...

Introduction This device is a Gauss sensor, which makes magnetic fields audible through a headphone: Acoustic Gaussmeter This is why I needed the Gausmeter: A hole had to be made in the concrete...

Elektronica online winkels met lage verzendkosten Bij het bestellen van elektronica onderdelen zijn bij kleine orders de bestelkosten vaak hoger dan de goederen. Dit zijn een aantal elektronica ...

A MOSFET graph has 4 quadrants (not just one) Low loss ideal diode circuits use MOSFETs in opposite direction to create the ideal diode. Here we must know that, in contrast to bipolar transistors,...