794.6875 is not a valid base frequency. It is the mobile channel associated with 764.6875, which is the 25 kHz channel center for the OLD channel 109-112. These lower channels were shifted up 5 MHz and the upper channels were shifted down 1 MHz to correspond with the elimination of the "wideband" channels in order to accommodate the D-block public safety broadband segment.
You're most likely hearing an image from one of the bases on site. If so, it's probably logically inverted, so it won't decode.
Be aware that there are "State License" 700 MHz frequencies that can be used as a hybrid section of an 800 MHz digital system. These 700 frequencies are not site-licensed, but blanket licensed to the state. You will not find them on ULS, but they can be used to augment loading in a system, or even as control channels. 109-112 is a "State License" channel.