Pagers may feel like a relic from the 1990s, but in many places they're still very much alive—especially in healthcare, industry, and some public-safety systems. With the right software and an SDR (software-defined radio), you can experiment with decoding pager signals in a controlled, legal way to better understand how these legacy systems work and how tones, addresses, and data formats are structured.
In this video and walkthrough, we'll look at how to use PDW—one of the classic pager-decoding applications—to receive and interpret pager traffic. You'll see how to install the software, configure the interface, and connect it to an SDR so you can visualize pager frames and activity where it's legal to do so.
Important: monitoring and decoding pager traffic may be restricted or illegal in some countries or regions, and pager messages can contain sensitive personal or medical information. Always check your local laws first, only decode signals you’re authorized to receive, and treat anything you see as private.
Step 1: Download and Install PDW
The first step to decode pagers with PDW is to download and install the PDW software. The PDW software is available for free from discriminator.nl/pdw. Once you are on the website, click on the PDW v3.12 link to start the download.
When the download completes, browse to the folder where the archive was saved, right-click the file, and choose “Extract All” to unpack the contents into a new folder. After extraction, copy that folder into your Program Files directory so PDW lives in a consistent, easy-to-find location on your system.
Step 2: Create a Shortcut
To make launching PDW quick and painless, locate the PDW.exe file inside the folder you just copied, right-click it, and select “Create Shortcut.” Move or copy that shortcut to your desktop, then rename it to something simple like “PDW.exe” so you can spot it at a glance.
Step 3: Set up the Interface
With PDW installed, the next step is to point it at the correct audio input. Open PDW, click the Interface tab, and choose Setup. In the interface window, select your preferred sound card or virtual audio device as the input source and leave the configuration set to the default earphone/line input.
Confirm that the baud rate is set to 44800, which is suitable for most common pager signals when using an SDR and proper audio routing. Under the Soundcard section, select Cable Output (or the virtual audio cable name you use to route SDR audio) and click OK to save your settings.
Step 4: Set up the Options
Once the interface is configured, it’s time to tell PDW which protocols to look for. Click the Options tab and then select Options from the dropdown menu. Enable Pocsag, and check the 512, 1200, and 2400 options so PDW will attempt to decode the most common paging speeds in use.
In the same options window, make sure all relevant FLEX modes are checked as well. This allows PDW to automatically detect and decode FLEX-based pager systems if they’re active on the frequency you’re monitoring. When everything is set, click OK to store your configuration.
Step 5: Tune Your SDR to Frequency and Output
With PDW ready, you can now bring your SDR into the loop. Use your SDR software to tune to a known pager frequency in your area and route its demodulated audio to the same sound device you configured in PDW. A narrow FM (NFM) mode and proper filter bandwidth will usually give the best results.
Keep an eye on the meter in the upper right corner of PDW—this should move as pager signals are received, and a percentage indicator below will help you judge audio quality and decode confidence. As valid pager frames come in, PDW will begin to decode them and show activity in the main window, allowing you to analyze traffic patterns and message structure within the limits of your local laws.
Frequently Asked Questions
Is it legal to decode pagers with PDW?
Laws vary widely by country. In the US the ECPA generally prohibits intentionally intercepting and using pager content. Many EU countries also restrict reception of pager traffic, especially when messages contain personal or medical information. Check your local rules before decoding any live traffic. PDW itself is just software and is fine to install and study, but using it on real pager signals may not be legal where you live.
What SDR works best with PDW?
Almost any SDR that can produce clean NFM audio works. RTL-SDR dongles, Airspy, SDRplay, and HackRF all decode pagers fine. The key is good frequency stability and clean audio routed into PDW through a virtual audio cable like VB-Cable. The exact dongle matters less than antenna placement and audio level.
What pager modes does PDW decode?
PDW handles POCSAG at 512, 1200, and 2400 baud, FLEX in its common modes, and ACARS aviation messages. POCSAG and FLEX are the two pager protocols you will encounter most often on VHF and UHF in North America and Europe.
Why is PDW not decoding anything even though I see signals?
The most common cause is wrong audio routing or wrong audio level. PDW needs the demodulated NFM audio routed in via the virtual audio cable you selected in Interface Setup, and the level meter in the upper right needs to register movement on the signal. If you see signals on the SDR waterfall but PDW is silent, double-check the soundcard input selection and that no other application is hogging the audio device.
What sample rate or bandwidth should I set in my SDR for pager decoding?
Use NFM mode with about 12 to 15 kHz bandwidth. That covers POCSAG and FLEX pager deviation without letting in too much adjacent channel noise. Set the demodulated audio sample rate to whatever the virtual audio cable uses, typically 48 kHz.
Does PDW run on macOS or Linux?
PDW is Windows-only. On macOS or Linux you can run it through Wine with mixed results, or use alternatives like multimon-ng for POCSAG and FLEX, or the rtl-fm plus multimon-ng pipeline that works natively on Linux. PDW is the simplest option if you have a Windows machine available.