ISO
Camera Isolate – This is not reserved strictly for the domain of cameras anymore. This is truly an isolate function, not unlike the action at a party of grabbing the arm of a fellow guest, dragging them off to a corner for a private conversation, and then returning them to their group. There are instances where it is necessary in an intercom system to establish a momentary private conversation with someone who may be talking and listening to a number of other people. The person who needs to interrupt presses a button or key, which establishes a private two person conversation. Upon releasing the key, the two participants are returned to whatever conversation(s) they were a part of previously. This was called Camera Isolate as it first was used to remove an individual camera from a conference to allow private communications.
Tally
A signal sent for the purpose of indicating status for a particular purpose. The sound of your telephone ringing can be described as a tally. On an intercom panel with multiple channels, it can be a visual signal, such as a blinking light, to indicate which station is calling. It can be used to indicate a particular function is not available due to a conflict – similar to the busy signal you get when calling the radio station trying to be the tenth caller and win a year’s supply of cat litter.
The above definitions and many more can be found in the glossary at the back of this book.
The Rest Of The Book
We have organized this book by the above types of systems – two chapters devoted to PL Intercoms, two chapters for matrix systems, two chapters for wireless systems, and one chapter on interfaces, determining systems needs and requirements, technical requirements for installation, and some real world case studies.
Near the end of the book, we have included references for further information, a glossary, and a CD full of information on Telex® Products, technical references, and many system drawings.
6 H a n d b o o k o f I n t e r c o m S y s t e m s E n g i n e e r i n g
