Nowadays it’s easy to have a video call with almost every part of the world. But it took a long time for the technology to reach this level. I will show what solutions engineers used back in 1988, so you could not only talk but also see your friend or partner during the call.

Once I saw a YouTube review of Sony PCT-15 — this device, made in Japan, was connecting to an ordinary telephone line and allowed not only to talk with another person but also to send and receive images during the call. …

My first PDA was Palm m105, I used it in 2001. 20 years later I decided to check, how the last generation of Palm OS devices was looking and to check if it’s possible to use Palm OS nowadays.

Palm m105 was a nice device for its time, it had a grayscale screen with a “stunning” 160x160px resolution and a 16 MHz Motorola CPU. Comparing to it, Palm TX looks much better — it was released 4 years later, and it has 312 MHz CPU, 320x480 TFT screen, USB, WiFi and Bluetooth support. …

Analog mobile phones were popular in the 90s and the last operators ended their service only in 2007. Is it possible to run this phone now? Let’s figure it out.

AMPS

Advanced Mobile Phone System (AMPS) standard was created by Bell Labs in 1983, these phones became popular in the 90s. This standard was a sort of first-generation cellular technology — the voice was transmitted using the “old way” method of frequency modulation (FM), like in a walkie-talkie radio, but the radio spectrum was divided into separated channels, and the so-called “control channel” was actually digital.

The AMPS is using 825–845…

In the 90s, pagers were popular: They were cheap, lightweight, and had very long battery life. But at the same time, they were only able to receive messages. There was no transmitter inside the pager, and there was no physical possibility to send any response. The idea of having two-way communication was tempting, and in 1995 the Motorola Tango, the first pager that was able not only to receive but also to send messages, was made.

Technology

All pagers from the paging provider listen to the same frequency, let’s say, 930 MHz. Every pager has its own unique ID, called CAP…

Pagers were popular many years ago, and some people may still have one at home. Is it possible to test the pager now? Absolutely, and I will show you how to do it.

Let’s get started.

POCSAG — The Messaging Protocol

In the 90s, I was a student and the pager for me was something like a Star Trek Communicator, a piece of the cutting edge technology. It is fun to remember it because now I know that technologically the paging protocol is very straightforward. …

Before we begin, it can be useful to remember the technological level of that time. The typical mobile phone, available for the customers in 1994, was a Nokia 2110, which had a 236g weight, a 25mm thickness, and a small monochrome 96x96 screen:

Laptops were heavy and expensive, smartphones were not invented yet, and nobody was even thinking about iPhone or Android at least for the nearest 10 years. Thus, an appearance in 1996 of a Palm Pilot device, that was relatively cheap and lightweight, that could be held in a palm and could work as a personal digital assistant…

Android 1.0 (2008)

Android OS has a pretty long history: the very first Android phone HTC Dream was announced in September 2008. It can be hard to find this phone, but we actually don’t need it — for developers, Google made an emulator of every Android version. The SDK for version 1.0 can be downloaded from the https://developer.android.com/sdk/older_releases.html page, and this is the only version, that even does not need install. It’s enough just to run the file tools\emulator.exe. At the first run we get the error:

Windows 95 was the “next-generation” OS from Microsoft: redesigned UI, long file names support, 32-bit apps and many other changes. Some of Windows 95 components are still in use today. How does it look? Let’s test it and figure it out.

I was not going to make a review of Windows 95, it was actually not so many years ago. But once I saw the video, something like “Teens react to Windows 95”, and it’s become clear that there are already not only teens but a whole new generation of 20–30 years old adults who never used Windows 95 in…