elektroda.com

The inside of the Polish retro power supply Polwat PWS-100 RM 24V/4A - has it survived the years of

p.kaczmarek2 — Sat, 09 May 2026 09:16:19 +0200

Today we take a look inside an old power supply made by a Polish company from Gliwice. I recovered the whole thing from scrap metal, so I'm going to check how this power supply has coped with years of use in an industrial device, examine whether it's still in working order at all, and finally show what heats up the most in it. The power supply shown here is the PWS-100RM model and is mounted on a TS-35 rail. It comes in different versions differing in output voltage, these include 5, 12, 24 and 48 V, although the documentation... Read more

How hot does the 24 W Tuya ceiling lamp get? Test, interior and firmware change

p.kaczmarek2 — Fri, 08 May 2026 12:41:49 +0200

How is the 'smart' remote-controlled Tuya lamp built? What Wi-Fi module is inside? To what extent does it heat up the interior when lit at full brightness, and can this heating be reduced somehow? Can this type of product be connected to the Home Assistant and used without the cloud? Let's find out! Let's start with the contents of the kit. What do we get when we pay a good 80... Read more

How many radios are in a radio? FM 87-108 MHz RDA5807S do-it-yourself kit

p.kaczmarek2 — Thu, 07 May 2026 10:13:58 +0200

What kind of soldering kit for a beginner? The HU-017A kit shown here costs just under a dozen zloty, and you can get it even cheaper in a promotion. It allows you to build a simple FM radio based on a ready-made RDA5807S module, a microcontroller with a 7-segment display for tuning and a TDA2822M audio amplifier. A slightly more expensive version with an enclosure is also... Read more

£1 Re-Use smart bulb finds: IKEA Tradfri LED2003G1, Ener-J SHA5262, unbranded PIR, Yichip YC1166 BT

divadiow — Tue, 05 May 2026 18:47:41 +0200

In the city where I live we have "Re-Use" shops alongside standard recycling centres (aka tips, dumps, household waste disposal facilities). These re-use centres are packed with donations and finds that would otherwise have gone into the general waste or recycled. Of course there's some stuff for sale that should probably have been binned, but a lot is fairly decent. This Re-Use centre in particular has 6 drawers of light bulbs. and at £1 for 4 bulbs, £0.25p each, there's potential to find some interesting smart bulbs in... Read more

Inside the UE55MU6452U big screen TV, analysis, decoding and flash simulation for the agent

p.kaczmarek2 — Tue, 05 May 2026 11:02:14 +0200

Ever wondered what sits in the Flash memory from a modern TV? I invite you to a short presentation of the inside of the Samsung UE55MU6452U 55" 4K UHD Smart TV combined with reverse engineering and emulation of the T-Con controller firmware. Here I will show how such a TV is built, how its backlighting is realised and what components can be recovered from inside. Finally, I will also try to rip the contents of the Flash memory from inside, decode it properly, determine its architecture, UART addresses and fire it up in a simple... Read more

Which silent lighting controller on Zigbee? Two-channel LZWSM16-2 without neutral wire

p.kaczmarek2 — Sun, 03 May 2026 11:34:56 +0200

Not everyone likes the distinctive loud click of relays accompanying the switching on of lights in most home automation products available. Nor does everyone have a neutral wire available in the box - in old installations it may have been unnecessary, and its absence makes it difficult to connect some of the 'smart' controls. The product shown here solves both of these problems at the same... Read more

Two tiny UPS for router, camera or Raspberry Pi - capacity test

p.kaczmarek2 — Sat, 02 May 2026 10:53:48 +0200

Today I am testing two small devices capable of temporarily backing up the power supply of a 5 or 12 V receiver in the face of an unexpected power outage. The first is a distinctive black box plugged into a USB cable, necessarily operating on 5 V only. The second is slightly larger, resembles the router itself in size, operates on 12 V and has 5, 9 and 12 V outputs. Let's start with the first one - you can vainly find the model name here, but you can also judge a lot by its appearance. The whole... Read more

Practical tests of Gemma 4 and comparison with Gemini 2.5 - image tagging and OCR

p.kaczmarek2 — Fri, 01 May 2026 09:19:02 +0200

Are modern LLM models run locally, on an old gaming laptop, able to meaningfully tag photos? Are modern models suitable for OCR and correctly recognise electronic circuits? I invite you to the Electrode test of artificial intelligence, this time enriched by the locally run model Gemma 4 and by the paid models gemini-2.5-pro and gemini-2.5-flash run via API. I'll check out a wide selection of newer and... Read more

Hisense AC WiFi module/protocol reverse engineering

DeDaMrAz — Wed, 29 Apr 2026 23:49:58 +0200

I am going to start this thread as a WIP for decoding (another unknown) UART based protocol. I am going to present the findings so far but in a rough state as I am still working on figuring out what is in the packets. Assumption that I started with was that the packet is similar to IR commands where multiple states are sent/reported all at once and I was not wrong. So here goes some of it. ### General frame structure | Byte offset(s) | Example | Working meaning | Confidence | | -------------- | ------------------------------------------------------ |... Read more

Controlling a 12V relay directly from a 5V MCU using a Zener diode and a PNP transistor

petrykcom — Wed, 29 Apr 2026 02:46:54 +0200

In engineering practice, there is often a need to control a relay or other receiver connected to a higher voltage (12V or 24V) using a signal from a microcontroller operating with 5V logic. The standard solution is to use an additional NPN transistor or optoisolator, which increases the number of components and cost. This article presents an alternative, industry-proven solution that requires only a single Zener diode selected to suit the supply voltage. The circuit has been used since the early 2000s in industrial controllers for the production of Europallets and still works reliably today. Assumptions Microcontroller supplied with 5V (e.g. AT89C2051, AVR, PIC) PNP... Read more

How a racing set is built - steering wheel and pedals for USB/Playstation and PS/2

p.kaczmarek2 — Mon, 27 Apr 2026 09:38:10 +0200

I recently presented the running of the PIC16LF1659 as an HID keyboard or mouse controller . A gamepad or joystick can also be realised in a similar way, it just remains to determine how to handle the buttons and axes. This is a great opportunity to take a look inside two products that I've had set aside in the attic for a while. The first piece of hardware to be showcased is the MX-V9 Vibration steering wheel, which works with either a PlayStation console or a PC... Read more

Simple clock on PIC12F683 - three pins, two I2C buses - DS1307 + FD650

p.kaczmarek2 — Sun, 26 Apr 2026 08:53:57 +0200

Today we are building a tiny clock with time keeping, we will realise it based on an 8-bit PIC12F683 microcontroller with only 128 bytes of RAM, a 7-segment display module with FD650 controller recovered from electro-junk and a DS1307 RTC clock. I will also show full waveforms from I2C communication captured with a logic analyser in the theme. Why not one I2C bus? Let's start with the most important design problem and the obvious question that probably occurs to everyone after reading the... Read more

Will the new GPT-Image 2 generate an electronic circuit diagram? Comparison with Nano Banana 2

p.kaczmarek2 — Fri, 24 Apr 2026 11:32:40 +0200

I invite you to a practical test of the new image generator from OpenAI. In this topic I will test the performance of GPT-Image 2 on various electronics related tasks, there will be drawing schematics, describing devices and also editing photos and graphics. In addition, I will compare the whole thing with the Nano Banana 2. Is the new model really better? Let's find out! A large part of the prompts and tasks in this topic have already been tested with the Nano Banana models, feel free to visit the related... Read more

Wi-Fi module in an electric kettle, what does it do? Interior and programming of Harmony 50

p.kaczmarek2 — Thu, 23 Apr 2026 11:28:05 +0200

I invite you to a demonstration of a Wi-Fi enabled electric kettle. Here I'll show how it pairs, what its mobile app offers, how it's built inside, and see if it can be altered with firmware to free it from the manufacturer's servers and connect it locally to Home Assistant. This will be the second kettle I've presented on the forum, as I already showed some time ago Changing the firmware of the SMART06B , but the Wi-Fi + kettle connection is so curios and interesting... Read more

DIP-encapsulated micro relays to be driven directly from the microcontroller/ESP pin?

p.kaczmarek2 — Tue, 21 Apr 2026 08:24:44 +0200

Today a little tidbit I came across while developing one of my projects. I was looking for a simple way to mechanically disconnect microcontroller/ESP controlled lines, with a minimum of additional components. This is how I came across the very small V23100-V4 dual signal relays. Interestingly, the manufacturer explicitly emphasises in the documentation that the coil can be controlled directly by TTL signals, which is immediately appealing for projects with... Read more

Custom pen drive from scratch - PIC microcontroller and EERAM memory - no external libraries

p.kaczmarek2 — Sun, 19 Apr 2026 08:42:22 +0200

What does it look like to implement a storage device driver in C? Can the tiny PIC16LF1459 microcontroller, with a modest 14 KB Flash memory and an even smaller 1 KB RAM, simulate a pendrive? Will it manage to write a text file to an EERAM 47L16 connected to it via I2C? Today is the time for an "art for art's sake" project - but who can forbid a programmer? I'll start by reminding you of two related topics I'll be building on here. About the PIC and the USB: [url=https://www.elektroda.pl/rtvforum/topic4171223.html] Tutorial... Read more

[BK7238 / T1UHL] Feit OM60/RGBW/CA/AG(N) Teardown amp; Flash Guide

TelemetryKernel — Sun, 19 Apr 2026 07:36:35 +0200

I bought a pack of 3 Feit OM60/RGBW/CA/AG(N) smart light bulbs The (N) in the model name seems to denote a newer revision from the already posted non-N version, as these use a Tuya T1-U-HL (Beken... Read more

Practical test of the Yihua 852D+ soldering station (2-in-1, hot air 700 W and 60 W 900M flask solde

p.kaczmarek2 — Fri, 17 Apr 2026 08:56:42 +0200

Two soldering irons in one kit and for only PLN 300 - is that a good deal? Here I'll introduce the Yihua 852D+ station and see how comfortable it actually is to work on a motherboard with it. I will test both a hot air and a flask soldering iron. I will take measurements at the 100°C, 350°C and 450°C temperature settings and check how much the sensor will actually heat up to. I will check the advertised asset of this station - the 24L/min diaphragm pump from the... Read more

PIC16LF1459 tutorial - USB HID support in the free SDCC compiler - LED, mouse and keyboard

p.kaczmarek2 — Wed, 15 Apr 2026 10:05:56 +0200

I invite you to a little adventure with the PIC16LF1459, an 8-bit microcontroller made by Microchip, distinguished by its hardware USB support with a minimum of external components. You don't even need an external oscillator - the built-in one has enough precision. Here I will run USB communication on it using the free SDCC compiler, all without external libraries. I will show here examples of HID applications, such as simple LED control, data exchange using a simple 'maths coprocessor' as an example, and then show how to realise... Read more

Minitest: DigiTOP VP-16Af voltage relay for photovoltaics

p.kaczmarek2 — Mon, 13 Apr 2026 10:23:56 +0200

PIC12F683 - two-channel dimmer and encoder support on 128 bytes of RAM

p.kaczmarek2 — Sat, 11 Apr 2026 09:46:08 +0200

Here is an account of building a two-channel dimmer based on an 8-bit PIC12F683 microcontroller and parts from electrical junk. The project will be written in C using the SDCC compiler. A single encoder will be used to control the brightness levels, and pressing the encoder will toggle the bar being controlled at the time. The PWM will be realised programmatically on a timer and interrupt, as the PIC presented here has only one hardware channel for pulse generation, and my assumptions require at least two strips to be... Read more

Inside the surge protector strip and USB power supply test - SFS133 Defender Surge Protector

p.kaczmarek2 — Thu, 09 Apr 2026 09:53:31 +0200

RE22-121000 Temperature Controller – Made in Poland – internal view

p.kaczmarek2 — Wed, 08 Apr 2026 10:15:29 +0200

Retro triple time relay - VL-34UKHL4 - gallery from inside

p.kaczmarek2 — Tue, 07 Apr 2026 10:39:19 +0200

Here’s a little curiosity for today. This piece of kit is completely outside my field of expertise and not from my era, but it might still be worth a look – an old triple timer dating back to the days of the USSR. The whole thing is built using semiconductors. Time to take a look inside.... Read more

Interior of the old Saia PCD2.M120 automation controller with expansion modules

p.kaczmarek2 — Mon, 06 Apr 2026 11:26:23 +0200

Some time ago I presented the interior of the Saia PCD2.C100 extension cassette , today I would like to show its main module, the PCD2.M120 base unit. The PCD2.M120 consists of an enclosure, inside of which is the main board and the bus for the I/O modules, and a cover with LEDs, display and PGU (programming) connector. The connectors for the expansion cards are located on the... Read more