You Can Still Use a Pager in 2023
How a Raspberry Pi will help you resurrect this classic communications device
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