Before revision: In addition to conventional repeaters which use back-to-back radios transmitting on different frequencies, obstructions in microwave paths can be dealt with by using Passive repeater or on-frequency repeaters , such as those that were manufactured by Peninsula Engineering Group, Inc .
After revision: In addition to conventional repeaters which use back-to-back radios transmitting on different frequencies, obstructions in microwave paths can be dealt with by using Passive repeater or on-frequency repeaters .