You Can Still Use a Pager in 2023

How a Raspberry Pi will help you resurrect this classic communications device

Dmitrii Eliuseev
Debugger
Published in
12 min readMay 2, 2021

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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 cutting-edge technology. It is fun to remember it because now I know that technologically the paging protocol is very straightforward. From the encoding perspective, the pager is not so different from the wireless doorbells that are selling now for 5$ in Aliexpress.

Let’s say we want to send a message “TEST” to the number “1234”. The message in a binary form will be looking something like this:

10101010101010101010101010101010 - Preamble
01111100110100100001010111011000 - Frame Synchronization Code
01111010100010011100000110010111 - Idle codeword
00000000000100110101111000111111 - Address + Function Bits + CRC
10010101101000111001001111111100 - T E S (7 bit/symbol)
11001010100000000000001111100011 - T . .
01111010100010011100000110010111 - Idle codeword

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Dmitrii Eliuseev
Debugger

Python/IoT developer and data engineer, data science and electronics enthusiast