Backup Automation/Silence Detection

Broadcast Tools Smart Silence Monitor

Last semester I implemented silence detection at WSBF, which is much needed because our commercial automation software crashes anytime it runs for about fifteen minutes.  I used a Broadcast Tools SSM silence monitor that I found in a cabinet at the station.  I assume the device wasn't being used because it is for analog audio and we use a digital signal.  I devised a way to make it work by having the SSM monitor the analog output of the STL, then passing the digital output of the STL through the normally closed relays and connecting the digital output of a computer to the normally open relays.  This works because the SSM doesn't interact with the signal connected to the relays at all, it just switches between them.  By having the SSM monitor the STL, it keeps the silence detection from being falsely reset when Backup Automation kicks in, which is what would happen if the SSM monitored the over the air broadcast or the output of the processor.  When two minutes of silence is detected, the SSM sends a pulse to our VRC2500 Remote Transmitter Control.  When this happens it tells the Lynx software to launch the Backup Automation software.  The program prevents multiple instances of itself from running, otherwise, every two minutes the SSM would send another pulse and Lynx would launch another instance of Backup Automation.  This program is a piece of software that I wrote in trusty Visual Basic 6, which I call Quick and Dirty Backup Automation.  The program and its source code can be found on the Solutions page of this blog.  It is pretty simple software; when launched it plays songs from a folder, and every four songs it plays a PSA from another folder and a station ID from another folder.  This week I went back to the code and added support for playing the station ID at the top of every hour to ensure we stay FCC compliant when the program is in use.  This software doesn't have a lot of features, but it does exactly what we need it to do, and it does it well.  The simplicity of the program is responsible for its key feature: reliability.  We've left the program running on a computer at the transmitter site for close to five months with no issues whatsoever.  Silence Detection and Backup Automation have already saved us from countless hours of dead air, and, at least until Zach Musgrave finishes his Automation software, it is definitely a necessity for WSBF.