Doorbell Light for the Hearing Impaired

Summary: The objective of this project was to create a visual signal on my treadmill to alert me when someone was ringing the doorbell. Why a visual alert? Well, because I invariably have music blaring out of my in-ear headphones when I’m running. Between that and the noisiness of the treadmill itself, I have, in the past, missed the delivery guy knocking at the front door. It is so annoying to have to go on a treasure hunt just to recover parcels that I could have easily received myself if only I had known someone was at the front door. The final device I settled on consisted of a large red flashing LED to get my attention, controlled by a 556 timer chip (which is two 555 timer circuits in one package). I then connected it through internal house wiring to the doorbell. In addition, I designed the enclosure housing this doorbell light to fit into one of the bottle holders on my treadmill's display console.

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Best Digital Multimeter for Electronics Work and for the Electronics Hobbyist

The digital multimeter is one of the most important tools in the electronics professional’s and electronics hobbyist’s toolbox, so much so that electronics aficionados usually have more than one. However, digital multimeters are used not only by electronics enthusiasts but also by other professionals such as car mechanics and electricians, who often have slightly different needs with respect to multimeter specifications. Consequently, the humble digital multimeter comes in a variety of different flavours which cater to the needs of different professions. Therefore, the electronics hobbyist needs to know beforehand what specifications are appropriate for electronics work, and what he or she should be looking for when buying a digital multimeter. So what's the best multimeter for electronics work and what should a newly-minted electronics hobbyist be looking for in their new digital multimeter? Let's try to answer those questions.

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Making a USB Temperature Sensor

Summary: The idea here was to create a temperature sensor that could easily be connected to an Apple Mac computer and have it display its readings inside an OSX application. More a demonstrator than anything someone might actually use in the real world, but who knows, maybe someone out there has a practical need for such a contraption...

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​Creating Hydrogen through Electrolysis

Hydrogen, a versatile element with a myriad of applications, serves as a crucial feedstock for various chemical processes. Beyond its role in chemical synthesis, hydrogen also holds promise as a cleaner energy alternative to traditional fossil fuels. Its clean-burning properties make it an attractive option for power stations, offering a pathway to reduce greenhouse gas emissions and combat climate change. In transportation, it also offers a cleaner fuel alternative for heavy vehicles such as trucks, buses, and construction machinery. There is even the potential for hydrogen-powered ships navigating our seas. The current method of creating hydrogen, however, steam methane reforming (SMR), raises environmental concerns due to its carbon emissions. This prompts a closer examination of alternative hydrogen production methods, particularly water electrolysis. In this article, we compare the established method of hydrogen production, SMR, with emerging water electrolysis techniques. By weighing the advantages and disadvantages of each approach, we aim to shed light on the quest for a more sustainable hydrogen production process that aligns with our collective goal of a greener future.

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USB Breakout Board for V-USB

Summary: The objective here was to make a USB breakout board that incorporates the hardware required to implement the mostly-software-based USB protocol, V-USB from Objective Development. The completed V-USB module can be connected to a range of Atmel AVR® microprocessors involved in various projects at the breadboard stage, obviating the need for additional USB circuit components to be added separately to the project breadboard whenever USB functionality is required. The use of V-USB where the USB protocol is incorporated into the main project AVR microcontroller also replaces the need for a dedicated chip to handle the USB protocol.

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The Different Types of Electric Motor

The electric motor stands as a cornerstone of modern engineering. It powers everything from household appliances to industrial machinery and now even the personal car. At its core, a standard electric motor comprises several key components working in harmony. A rotor sits within a stator usually surrounded by an enclosure or frame. Differential energisation of electrical coils within the motor facilitate a changing magnetic field which induces the rotor to turn. There is usually some way to mount the motor, as well as a way to wire it to a power source. Together, these elements form the fundamental structure of the electric motor, converting electrical energy into mechanical motion with remarkable efficacy. In this review, we look at some of the different types of electric motor in use today. These different devices are distinguished by their internal workings which usually also determines their suitability for a particular application.

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The Best Robot Vacuum Cleaners in 2024

The world is in the midst of a robotics revolution, and the humble vacuum cleaner is leading the way. It is no surprise then that the number of robot vacuum cleaners available to consumers has increased almost exponentially as new entrants have entered the market and competition heats up. This is great for pushing robotics technology forward. Indeed, the number of features on these obedient machines and their level of intelligence continues to increase. However, the rapid pace of change can also make for a confusing picture. To help you decide which robot vacuum cleaner is best for you, we have looked at the range of robot cleaner offerings in detail. The focus here is on the current state of the technology and determining the key features to pay attention to when purchasing one. 

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USART Debugger on the AVR Microprocessor

Summary: When trying to build an electronic device based around a microprocessor, it's useful to have the microprocessor itself send back updates as it executes its code so that one can debug any problems with the device. The microprocessor type that I invariably use is an Atmel 8-bit AVR (most often the ATmega168) so this write-up will be focused on getting that system to work. So how do we get these debugging messages from the AVR microprocessor? One way is to use the USART capabilities of the AVR to communicate with a computer via an RS-232 serial connection. Although the RS-232 serial connection represents an older way of doing things, it does work just as well, for our purposes anyway, as more modern methods, and is especially appropriate if you have an old unused computer lying around that could do with a new reason to live!

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Exploring UHF RFID: Power, Modulation, and Global Standards

Radio Frequency Identification (RFID) technology is increasingly being used to track just about everything. Indeed, applications of the technology include diverse areas ranging from business inventory management to crowd control at large public events. As we delve further into the era of the internet of things, the use of RFID is expected to rise even more. There are a number different types of RFID technologies in use today, differentiated by the electromagnetic frequencies they use and whether their tags are passive or active. One type of RFID tag technology that has been growing in use more recently is that which uses the Ultra High Frequency (UHF) band of the electromagnetic spectrum. The UHF band encompasses radio frequencies from 300 MHz to 1 GHz, but the UHF RFID tags and readers that are making the most waves recently are those that use the 860 MHz - 960 MHz portion of the spectrum. But how exactly do UHF RFID tags work?

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Are FPGAs the Future of AI?

Diagramatic representation of the components inside an FPGA chip

An FPGA, or Field-Programmable Gate Array, is a programmable semiconductor chip enabling the implementation of various electronic circuits by circuit designers. Unlike fixed physical circuits in traditional processors, FPGA's digital circuits can be configured and reconfigured for diverse tasks. Importantly, no physical changes occur during FPGA programming. Instead, a matrix of programmable logic blocks and interconnects exists within FPGA chips, allowing construction of desired electronic circuits by enabling/disabling as needed. This flexibility is valuable for developing device prototypes or optimising electronic circuits for real-world applications. Today, FPGAs are proving valuable in Artificial Intelligence, raising the question of whether they will be the key processor in future AI.

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