I am sure this is most likely a dumb question but I couldn't find the answer. This past weekend I was down in Columbus and took the Pro-106 along with me. While listening to the Franklin County system I noticed that sometimes when a console keyed up there was a beep to start the transmission. What is this beep and is it common on motorola systems? The one and only motorola system I did monitor did not have these beeps and has since been upgraded to p25 so I'm not very familiar with motorola systems.