December 5th, 2005, 05:30 PM
Join Date: October 17, 2005
Location: Middle Tennessee
HOW TO: POCSAG/FLEX PAGER MONITORING (and more)
Who the hell uses a pager anymore? I'm thinking not many of you, but you'd be surprised at the number of companies that still use old pager technology. What's great is that these messages can be monitored with a scanner, and then decoded with a computer.
-First thing is you'll need a scanner that can recieve pager frequencies (most can).
-Second is you'll need a computer, preferably a 486 or faster. I only put this in because some of us are very ghetto.
-Your computer needs to have a sound card with a line input. If you only have a mic input (like me) you'll need to bodge up a cable with a resistor in it to tame down the signal. I used 10k, YMMV.
-You'll need a cable to go from scanner to computer line input. Usually 1/8" to 1/8". If you only have a mic input then just use the resistor method above.
-Lastly you'll need a wonderful piece of software called PDW.
The first thing is to set up the scanner input cable and set your computer to the line (or mic if you dont have line) input. I'll leave this up to you. Next, download PDW. The latest version is 2.13. Download it at http://www.downloadcounter.com/cgi-b...nter&account=3
Unzip PDW. In what you unzipped you will see another zip, xp_driver.zip. This is a driver for a serial port interface, we won't be needing it but the program won't start without it so just unzip and install.
Go back to your PDW folder and read PDW.HLP just for kicks. Ignore the parts about tapping the discriminator if you are using the soundcard input, that's bullshit. You don't need it.
Now fire up PDW (PDW2_13.EXE). Go to Interface>Setup and check Soundcard. Make the sampling rate whatever you want, although I'm thinking the higher the better. More clarity. I used 44100. For configuration, you'll want to play around with that a bit. I got good performance with the standard Earphone 1 but using Tape/Rec Out 1 was even better.
Once you have this set, click OK in the window and then go to the Monitor menu and check POCSAG/FLEX.
Program some of these frequency ranges into the Limit Search of your scanner:
* 453.025 - 453.125
* 454.025 - 454.95
* 35.02 - 35.68
* 43.20 - 43.68
* 459.025 - 459.625
* 929.0125 - 931.9875
Once you find one single frequency that has a lot of transmissions on it (I found 454.90 to be rather popular) program that frequency into your scanner. Set your scanner to the freq you just programmed and set the squelch to the lowest setting or whatever setting makes you hear white noise (snow) 100% of the time (except for transmissions of course).
To make sure you find a good frequency that has POCSAG/FLEX transmissions on it, you should listen for this.
booo deeee crark boooo deeeee ......................... beeeee dooooooooo drrrt .......... kerchunk
booo deeee ddrttdjhdvvdrdrdhadrghsgrhdghrgdrg .................... drrt kerchunk
The first one is an i don't know, the second one is a transmission coming in.
If you have your scanner connected to your computer and PDW running, you might be having messages appear already. If so, then everything is set up ok and you are finished. If not, look to a little meter in the top right of your screen. When there is just random noise, the meter will flicker at the very bottom. When a valid transmission comes in, it will swing up to the maximum. If it just stays either not moving at all or just flickering at the bottom all the time (including when there is a valid transmission), increase the volume of the output of your scanner.
If you STILL are having trouble, then your scanner is recieving a weak signal (staticy). Find a different frequency.
Also you decode other types of data, look in the menu. ACARS messages sound like "clarp".
i would like to try this but i dont want to spend money on a scanner... send me one?
All is fair in love and war.