Eric - let me try to explain. WMNF is a very mountainous area. One repeater site cannot adeequately cover all areas, therefore multiple repeater sites are needed. All of the repeaters use a common input freq and a common output freq. In order to prevent multiple repeaters from activating at the same time, different PLs are used on the inputs of the various repeaters.
You have to be familiar with "repeaters" and with "PLs / CTCSS" in order to get a good handle of the WMNF radio system.