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Best budget-friendly optical reflectometer

Best budget-friendly optical reflectometer

Price-to-performance ratio. What accessories and equipment are necessary? The main criteria for choosing an optical reflectometer.

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DIY ProCo RAT: The True Vintage Distortion Pedal

DIY ProCo RAT: The True Vintage Distortion Pedal

Welcome to my guitar effects workshop! This scheme is already 46 years old. If you want tons of vintage mojo, you should consider assembling of this guitar pedal.

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Color space basics for HDMI video

Color space basics for HDMI video

Between resolution and color, the latter is more about perception. Yet it can be described as a mix of color space picked, the importance of back lighting, and the effects of subsampling.

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PWM LED dimmer

PWM LED dimmer

Let's assemble a completely analog PWM LED brightness controller using four operational amplifiers and figure out why PWM is needed and what it is.

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Review, teardown, and testing of LRS-75-24 Mean Well power supply

Review, teardown, and testing of LRS-75-24 Mean Well power supply

We teardown and tested in different modes LRS-75-24 power supply from Mean Well. It's a 75W single-output enclosed power supply with a low-profile 1 1/5" design. The device has extremely low no-load power consumption (less than 0.3W).

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Search for intermittent faults, and Pupin coils using a reflectometer.

Search for intermittent faults, and Pupin coils using a reflectometer.

Intermittent defect: wait or fix? Why is it specifically a reflectometer? Pupin coils are now obstacles to digital services.

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How does binary logic work? Shift registers

How does binary logic work? Shift registers

What do you do when the controller doesn't have many pins to connect buttons, indicators, relays, etc.?

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HDMI wiring and pinout

HDMI wiring and pinout

HDMI is the go-to standard for video output (and, subsequently, input). Partly thanks to its simple, backward-compatible standardized plug. But still, there are a bunch of different cables out there and an odd-looking tiny HDMI port on some devices, so what's the deal here?

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LED strip amplifier / LED amplifier / RGB amplifier. Features, problems, choice.

LED strip amplifier / LED amplifier / RGB amplifier. Features, problems, choice.

A seemingly simple thing - an LED amplifier. The user chooses a device of suitable output power and uses it. But the devil lies in the details. From this post, you will know how LED strip amplifiers differ, what is not written in the documentation, where and in what lies, and what problems these devices can create. And also any buyer wants to understand why these simple devices have a large price range.

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Finding branches using a reflectometer

Finding branches using a reflectometer

How cable branches are formed? What's wrong if a branch is? Methodology for locating the branch connection point

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Power control unit for testing

Power control unit for testing

This simple and inexpensive unit will help test various devices; with it, one can determine the power factor of the AC grid draw, power-on and power-off times, etc.

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Marshall Guv`nor: a Pedal that sounds like a Tube Stack

Marshall Guv`nor: a Pedal that sounds like a Tube Stack

When it comes to clean guitar tone, we all think of Fender amps. And the overdriven sound is, of course, Marshall. Can a small transistor pedal replace a real tube amp? - Let's try and listen!

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HDMI standard and functions

HDMI standard and functions

HDMI is the most common interface for video signals. But what is HDMI, and why is it so popular? And what should we know about it?

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PWM frequency in Shelly RGBW2 controller

PWM frequency in Shelly RGBW2 controller

The poor quality of light (flashing) in Shelly bulbs and LED controllers damages your eyes. However, the cause of light flickering (PWM frequency) can be fixed with your hands in 10 minutes. How can we improve the light performance?

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Finding water damage in a cable using a reflectometer

Finding water damage in a cable using a reflectometer

Signs of water presence in the cable Methods for locating cable water ingress points What if there's a fault in the waterlogged section of the cable?

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Review, teardown, and testing of RSP-320-24 Mean Well power supply

Review, teardown, and testing of RSP-320-24 Mean Well power supply

We teardown and tested in different modes RSP-320-24 power supply from Mean Well. It's a 24-volt power supply with a maximum current of 13.4 amps. The supported mains voltage is from 88 to 264 volts without an additional switch.

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VGA videocard for microcontrollers. Part 2

VGA videocard for microcontrollers. Part 2

In this second part, we'll examine how to transform a successfully prototyped idea into a physical product. Several key aspects need to be reconsidered.

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VGA videocard for microcontrollers. Part 1

VGA videocard for microcontrollers. Part 1

Sometimes, when making your own devices on microcontrollers, there is a need to display huge amounts of information on a display and to use a bigger screen for ease of perception. Unfortunately, there are no ready-made and budget-friendly solutions for this task on the market.

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Power supply characteristics. Turns the AC/DC power supply on and off. Low-cost parameter measurement.

Power supply characteristics. Turns the AC/DC power supply on and off. Low-cost parameter measurement.

What characteristics are important? What do the characteristics mean? How to measure parameters cheaply?

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Pi Extension board "PiEBridge" adapters

Pi Extension board "PiEBridge" adapters

PiEBridge has built-in programmable power supply for external/target devices and two connectors IDC6 and IDC10. More details in the post.

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