YouTube user NeedSec has posted a useful tutorial video showing how to set up decoding of FLEX 1600 pager traffic on a Windows system using PDW, SDRSharp and an RTL-SDR USB stick.
The RTL-SDR software defined radio combined with SDRSharp, and a POCSAG/Flex capable decoding application can be used to decode pager messages. With this setup you can receive pager messages from all pager users on the system. If you don’t know what a pager is, since they are now uncommon, here is a brief explanation from Wikipedia:
A pager is a wireless telecommunications device that receives and displays numeric or text messages, or receives and announces voice messages.
Not many people use pagers these days with mobile phone text messaging being used more, but pagers are still popular with doctors, some fire and ambulance agencies and various service companies, as they tend to be more reliable and have greater coverage. In most countries it is perfectly legal to receive these messages, as they are plain text unencrypted, but it is illegal to act on the information received. Please respect your local laws.
Here YouTube user Superphish shows 5 minutes of pager decoding using HDSDR, PDW and an RTL-SDR.