Nowadays everybody knows MacBook or iMac. But when the first “Mac” was released, and what did it look like? Let’s test it and figure it out.

Hardware

In 1984 the Apple company was not a beginner on the market. The previous Apple II model had been on sale for several years. It had a sort of primitive OS, based on the BASIC programming language and the minimum ability to work with disks and files, but the computer was cheaper than its competitors and, unlike CP/M machines, had the ability to display graphics. The next model, Apple Lisa, was too expensive ($…


Nowadays everybody knows Apple. But how did it start and can we run Apple ][ apps today? Let’s figure it out.

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Apple ads from 1980 © The Byte Magazine

It’s interesting to know the computer's history. To know, how the UI evolved from big mainframes to modern tablets, to know when the first mouse was made, was it easy or not to use the text-only interface, and so on. It was also interesting for me to know, how people were using computers before I was born. And the last but not least, I was also working 5 years as an iPhone developer, so “digging” to the very beginning…


I was already using my Samsung S10 phone in the DeX (“Desktop eXperience”) Mode, and in general, it was working almost good. Now, in 2021, I bought the newest Galaxy S21 Ultra, which costs actually more than my PC. Can this phone replace it? Let’s figure it out.

Before we start, a small note. I bought the Samsung S21 Ultra phone at my own expense. It was not sponsored by Samsung or any other company. So I will tell my experience “as is”.

Let’s get started.

What Is Samsung DeX?

DeX is a technology, that Samsung is developing for several years. The idea is…


I work as a software developer for many years, the very first systems I tried to write programs for, were MS-DOS and Windows 3.1. Once I got curious — how people used computers in the old times before I was born?

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Now it’s easy to get an answer to this question — we can run this system on a modern PC. I will show how to set up the CM/M emulator and run some of the original software of that time.

Hardware

Before we start, it’s interesting to see what sort of hardware was in use. …


In the IT world, there are some events that can be called landmarks in computing and engineering history. One of these was the creation of the first personal computer.

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In those years, computers were used only by scientists and engineers in big companies. And then, in 1975, a device was created, which anyone can afford. The Altair 8800 contained an 8080 processor, 256 bytes of memory in the first version, and was priced below $ 1000 — it was the first commercially successful personal computer. …


Gadgets and wireless technologies are now used everywhere. But it is even more interesting to see how it all began, what technologies have changed our life. Having found an online archive of old magazines, I decided to trace what was the cutting-edge of technological progress for our great-grandmothers and great-grandfathers.

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Television News, 1931

Before we begin, a small addition. Firstly, I am an engineer and not a historian — perhaps not all dates in the text are 100% correct. Secondly, I probably missed something, the volume of this article is not enough to cover everything that was created within a last century. …


One of the interesting data protocols developed in the last century is APT (Automatic Picture Transmission). It is used to transmit images of the Earth’s surface from space, and what is much more interesting for us, receiving APT signals is feasible to radio amateurs.

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NOAA Satellite © en.wikipedia.org/wiki/NOAA-15

General Information

The NOAA meteorological satellites, we’ll try to decode, belong to the TIROS (Television InfraRed Observation Satellite) series, the first of which was launched in 1960. There are currently 3 satellites in operation (NOAA-15, NOAA-18 and NOAA-19, the oldest of which, NOAA-15 works since 1998). The satellites orbiting around the Earth at an altitude of about 850…


Every year a series of ARISS Slow Scan TV (SSTV) transmissions are scheduled from the International Space Station, the images are transmitting using the 145.800 MHz ham radio frequency. How can it be received and decoded? Let’s figure it out.

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Image source https://en.wikipedia.org/wiki/International_Space_Station

General Information

The images transfer from the ISS is carried out by the ARISS team, the quite noble goal of this project is to draw attention to space exploration and astronautics. These broadcasts are carried out several times a year, anyone in any place of the world can receive SSTV images at the 145.8 MHz frequency. The SSTV (Slow-scan television) format itself…


Wireless technologies are now everywhere around us. But how does it really work? I will review different types of modulation and signal transmission modes, from the simplest to the most complicated.

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Let’s try to figure out, without formulas and as simply as possible, how we can transfer data from point “A” to point “B”.

OOK (On-Off Keying)

The simplest form of digital coding. Just turn on / off the radio transmitter in accordance with the binary signal:


The reason for this article is, in fact, sad. The world-famous radio telescope of the Arecibo Observatory in Puerto Rico has collapsed and is beyond repair. For many years it was the largest radio telescope in the world (diameter 304 m, frequency range up to 10 GHz), with the help of which many discoveries were made. On this Wikipedia image it is still in working condition:

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Source: Wikipedia

But the article is actually about another event. In 1974, a message to extraterrestrial civilizations was sent into space from this telescope. How it was encoded, let’s figure it out.

Encoding

First, it’s interesting to…

Dmitrii Eliuseev

Python and IoT Developer, science and ham radio enthusiast

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