A repeater is a set of radio's that receives signals and then retransmits them on a new frequency for the purpose of extending the range of portable and mobile radio's. A 1 watt handheld radio while within the range of a repeater can communicate to anyone that can hear the repeater. Repeaters are usually located in locations on hills or tall towers to increase their range. The repeater must either use two antenna's or have a special filtering device called duplexors to allow the same antenna to be used for transmitting and receiving at the same time. Some repeaters have a connection to a phone line so outgoing calls can be made from portable equipment. This is especially handy for cars that get stranded and need a tow truck, or for calling in an accident to the police. Access to repeaters is sometimes limited by use of subaudible tones. To access the repeater your transmitter must include a tone generator on the correct frequency. This is done to limit interference when there are users of other repeaters accessing the repeater unintentionally


The WN7C repeater is located in Mt. Gilead, Ohio. This is 45 miles north of Columbus Ohio. The repeater is a Motorola Micor base station commercial repeater that has been retuned to 146.775MHZ transmit and 146.175MHZ receive frequencies in the 2 meter amateur band. The transmitter power is 100watts. I have added an Advanced Receiver Research Gaasfet preamp to increase the performance of the receiver. The originall controller was homemade and featured activity timers, a talking clock, a phone patch, a PL decoder and a remote base to another repeater on 224.940Mhz. After a lightning strick that damaged everything the controller was replaced with a Cat700 repeater controller.  The duplexors are 4 cavity Sinclair ring duplexors. The antenna is a Ringo Ranger ARX2. The antenna is side mounted on the tower at 110' above ground level, approximately 1300' above sea level. .

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