w4rez said:
A similar question: Is there a reliable way to determine these tones from on the air monitoring or recording without purchasing hardware? I have tried several different pieces of AF spectrum analyzer software and found the results to be very dissatisfying.
Using just my PC equipped with a fairly standard sound card I was able to use a couple software applications. The only other hardware was a patch cord from the speaker jack to the Record jack. I then used the computer speakers to listen to the scanner, and turned off the computer speakers when recording the scanner unattended.
I record the tones using the free ScannerRecorder software, and then analyze them in Adobe Audition. Audition ($130 for educational users, $300 for others) is a great tool for this, the frequency is displayed just by clicking on the wave form. After playing with it for half an hour you will be able to tell just by looking at the waveform where the various tones are and be able to navigate around a recording. I can even tell which dispatch console is sending the tones by the shapes of the gaps before and after tone sets!
I usually record a fire channel for a couple days with ScannerRecorder, and then open the resulting wave file in Audition. Since there is a lot of voice traffic on the channel I often will snip out tone sets and save them as smaller .wav files. Don't forget to save enough of the voice message to identify the call ("Mayberry Fire, Station 1, an EMS run...")
Using this method I was able to identify about 400 different tone sets in the suburban Chicago area over a period of a month or so. With several other members of CARMA we were able to determine almost 700 tone sets in the larger area and we started a database of them on our Yahoogroup (
http://groups.yahoo.com/group/carmachicago/).
There are other programs that will analyze tones as well, including freeware or shareware that would be cheaper than Audition. I was able to get the educational discount due to a course at NU I was taking, otherwise I wouldn't have spent that much money on it.