POCSAG Receiver
Decode pager messages
What it does
SimpleBefore mobile phones, people carried little gadgets called pagers (or 'beepers') that could receive short messages. When someone wanted to reach you, your beeper would buzz and show a phone number or a bit of text. Some hospitals, restaurants, and services still use them today because they're simple and reliable.
This app can catch those beeper messages out of the air and show the text on screen. It's a fascinating window into a technology from before smartphones — and a great way to learn how digital text can travel by radio.
How it works
SimpleThe pager signal flips between two slightly different tones to spell out 1s and 0s — like a very fast game of high-note/low-note. A special 'get ready!' pattern comes first so the receiver knows a message is starting, then comes the pager's ID number, then the text. The app listens for the 'get ready' pattern and reads everything after it.
How to use it, step by step
Simple- Open the 'POCSAG RX' app.
- Set it to a pager frequency used in your area.
- Leave the speed on automatic.
- Wait for a message to arrive.
- Read the decoded text and ID number on the screen.
Examples
Observe how address codewords and message codewords interleave inside a POCSAG batch, and watch the sync word repeat.
Turn auto-detect off and try each baud rate to see which one cleanly decodes a given system — a good feel for how baud affects sync.
Compare a numeric-only pager (just digits) with an alphanumeric one (full text) and see how the function bits differ.
Tips & things to try
- Can't find a channel? Sweep 137–160 MHz and 450–470 MHz — paging lives in different bands by country.
- If text comes out as garbage, the baud rate is probably wrong — let auto-detect settle or step through 512/1200/2400.
- The RIC identifies which pager the message is for; one channel carries many different RICs.
- Reception is passive; treat it as protocol learning and respect the privacy of message content.