POCSAG Transmitter
How pager encoding works
What it does
SimpleThis shows how the kind of message an old beeper receives is put together — how a pager's ID and its text get packed into a radio message. It's a great way to understand the paging system you decoded with the POCSAG receiver, now from the other side.
Actually sending pager messages only makes sense on a pager system you own or are allowed to run, but understanding the encoding is valuable on its own.
How it works
SimpleTo build a message, the app first says which pager it's for (an ID number), then packs the text into blocks of code with a little math added to catch mistakes, and wraps the whole thing in a 'get ready' pattern so a receiver can lock on. It's the exact reverse of what the POCSAG receiver does when it reads a message.
How to use it, step by step
Simple- Open 'POCSAG TX' to see how a message is assembled.
- See where the pager ID goes and where the text goes.
- Notice the 'get ready' pattern and error-check codes.
- Compare it to what you saw in the POCSAG receiver.
Examples
Conceptually pair TX encoding with RX decoding to see the full paging round-trip on your own equipment.
Map a message to its address and message codewords and see how they interleave in a batch.
Compare 512 vs 2400 baud and reason about speed versus robustness.
Tips & things to try
- This is the mirror of the POCSAG receiver — learning both sides cements how paging works.
- Only transmit on a paging system you own or are licensed to operate.
- The BCH parity is a tidy, real-world example of forward error correction you can actually inspect.