The first pic is from Kavouras, the second is a WSI mosaic. They could dial into the WSR-57 or 74 radars in the first example (both radars were equipped with the same digitizing equipment). In the second example, WSI would connect to the radar sites, composite the images on a single map and perform quality control (ground clutter and other non precipitation echo removal). When the WSR-88D radars came online, the mosaics contained data from all three radar models for a few years.
From the footage we have, TWC began using mosaics in mid 1989 on-air and discontinued using the single site images later that year. They also used MDR (manual digitized radar) images in the 80s, which was a very low resolution picture (the radar operator actually had to enter this in an alphanumeric format of this based on a 20x20 km grid overlayed on the radar screen).
Here's two MDR images (numbers represent echo tops):
