Re: Quasi-Simulcast? A quick answer to your question.
True Simulcast requires and meets a technical standard using equipment made and installed for the task. Some of the analog simulcast system key issues are frequency stability, synchronization and equaliziation of both the audio and the ctcss/dcs signaling. When you depart from a true simulcast system with various equipment, engineering and technical hybrids then Quasi-Simulcast is often the label attached. Based on the specifics of each system and application there are many cases where some types of Quasi-Simulcast systems work quite well. ...and now a quick example or two... A County has two large towns separated with distance or an obstruction (large hill or mountain). One large same frequency-same audio transmitter at each town/city location key (at the same time) from the same dispatch center. .... or you have one really large city/area with two cross-town high powered transmitters. The coverage area of the two transmitters easily overlap in many places. If the system was properly designed and the equipment properly set up... any common location where the signals combine the mobiles will hear both transmitters. Again... many things come into play with this simple example... but in many cases/examples the dual or multiple tx radio system will work pretty well even if the equipment is not actually a true engineered and installed simulcast system. By the nature of how FM radios capture a stronger signal and the actual difference in those received signals directly determines how well your quasi system will work out. "Hopefully" a true simulcast system integrates the coverage overlap for the users so they always hear a clear usable signal in the overlap areas. By using strong (high powered) transmitters you also try to get enough signal into desired weak signal areas. A quasi simulcast system tries to achieve the same goal... often with "less equipment". If you pay attention to the details it is quite possible to make a quasi simulcast system work very well. cheers, skipp skipp025 at yahoo.com www.radiowrench.com
