The EXB-232 System Extender Modules are used in pairs to connect two MCN networks together over asynchronous serial channels, extending the length of an MCN network beyond 4000 feet. The EXB-232AY System Extender Modules allow the control of multiple remote comparators from a central site, simultaneously monitoring and controlling Master and Slave comparators in wide-area voting systems. Multiple pairs of EXB-AY modules can connect multiple MCN networks in real time, spanning distances from a mile to worldwide. Data transfer between distant networks is "live", delayed only by the transit time through the EXB modules and the data rate across the link. The EXB-232 System Extender Modules can utilize microwave channels, digital channel banks, or T1/E1 digital phone lines.