TO: ALL WEST VIRGINIA ARES MEMBERS (OFFICIAL)
ALL ARES AND NON-ARES AMATEURS ANYWHERE (INFORMATION)
FROM: KEN HARRIS WA8LLM WV SECTION EMERGENCY COORDINATOR
WOOD COUNTY EMERGENCY COMMUNICATIONS INCORPORATED
WV ARES BULLETIN NR 08.50 DATE: December 14, 2008
SUBJECT: WHAT IS A SIMPLEX REPEATER?
In last week's bulletin titled "NOT ALWAYS THE BEST QUALITY", I talked about a Simplex Repeater, but failed to explain what it is.
A Simplex Repeater is a voice radio repeating system that operates on one frequency as opposed to a Duplex Repeater which receives voice signals on one frequency and re-transmits them on another. Both Duplex and Simplex Repeaters have their pros and cons, but they both do the same job, they extend the communication range of mobile and handheld radios over a larger area.
The Simplex Repeater records any signals that it hears on the frequency, and re-transmits them back out on the same frequency. One disadvantage of a Simplex Repeater is the time that it takes to do the job. It takes as long time to re-transmit the signal as it took to record it, which only stands to reason. The Simplex Repeater only uses one frequency, instead of two, to do its job, which means it doesn't take up additional radio frequencies that can be used for something else.
If two operators are within hearing range of each other the simplex repeater is not needed, but there may be no way to turn it off, so it will record each conversation and then repeat it. This will cause a delay of the two operators talking to each other. However, since the simplex repeater is recording the conversations, it is repeating the same information which might sometimes help, especially if one of the operators has missed the information the first time. He can just listen for the repeated information without having to ask for a re-transmission.
Ken Harris WA8LLM
Wood County WV
WV ARES Section Emergency Coordinator
WV ARES District 3 Emergency Coordinator