Sunday, January 15, 2012

Skype for Intercom and Public Address System



Skype is a multipurpose communication tool.  It is NOT just IP voice and video phone software. With just a little bit of creativity it can replace all kinds of fancy electronic equipment costing thousands of dollars.  A few weeks ago, an organization I belong to decided to address a problem in its communication system.  
Specifically, the question was posed:  

"As many of you know, we try to enable the nursery workers to hear the service going on in the main building.  The present method is a baby monitor setup, but it's not really satisfactory.  If any of you (or your friends/relativesJ) have an idea for getting the sound from the auditorium over to the nursery, or would like to research the problem, I would really appreciate it.  Audio systems are not one of my skills."

I replied: 
"Use your WIFI network or extend it as necessary, and then initiate a VOIP "phone" call (eg. Skype) from the auditorium to the nursery.  Skype runs very nicely on a smartphone and the audio quality will be more than satisfactory.  Assuming the WIFI is in place and that people have smartphones or laptops, everything else is free."
The alternative they were considering was a PA system, wireless or hard-wired, costing well over $1,000.  On the basis of a satisfaction guarantee and a cost estimate that was a small fraction of the alternative, I received permission to go ahead with my plan.  
  • On eBay, we bought a refurbished iPod Touch (latest generation) for $140.
  • We acquired a used Windows laptop and speakers.  Value: $150.
  • We boosted the WIFI signal at both ends to reduce the possibility of dropped Skype calls.
  • Skype was downloaded onto both the iPod and the PC. Separate Skype names were procured and they exchanged contact permission.  There was no need to purchase Skype credits.
  • The PC was set up in the nursery with the following special configurations: 
    • Computer would run 24/7 with the lid down.  It would be attached to a set of speakers sufficient for the nursery.
    • Skype would remain open, ready to answer incoming calls automatically from approved contacts (one and only one contact).  
    • The microphone was muted (system software) so that nursery noises would not be heard in the auditorium.
    • Because of a further decision to record the events in the auditorium, we installed recording software on the PC (freeware), and set it to record Skype calls automatically with recordings going into a "Dropbox™."  
  • The iPod Touch was set up in the auditorium as follows: 
    • A piece of Velcro was put on the back, and the iPod was appointed to be attached to the podium (but removable for a speaker who wished to move around with the "microphone"  in his pocket.
    • Power was provided at the podium to eliminate any worry that the iPod might run out of juice, so it is provided with a USB power cord to the power outlet.
    • Skype was configured to "never" go offline except when deliberately taken off.  This means that the screen can be turned off during an event without hanging up the call.
    • After some testing we determined that the iPod's internal microphone was more than adequate.  Therefore the Lavalier microphone we had purchased was returned.
The process of broadcasting an event to the nursery (or to any location) is now accomplished simply by placing a Skype call, which is automatically answered by the computer at the other end. The one-way channel provides crystal clear sound and is turned off by just hanging up the call at the podium.  Non-technical managers are able to handle the setup with no problem, and if the speaker needs to wander away from the podium, he merely takes the iPod off its Velcro holder and slips it into his shirt pocket.  The new system has completely replaced the baby monitor PA system. The sound quality is vastly improved.
The new system has also replaced the former recording system that used wireless microphones. The new recording system automatically records Skype calls and deposits the audio files into an assigned "Dropbox™" which is then linked from the website.  The entire recording infrastructure has been replaced with free software.
    If our purpose had been to broadcast a video feed to the nursery instead of just audio, Skype would have again comprised the solution.  Also, if we ever need to broadcast an event off the campus or even to multiple remote locations simultaneously, that should present no difficulty either.  Skype is proving to be a multipurpose communications tool that solves a myriad of problems.