The Tektronix DSA 602 is a digital scope with waveform processing capabilities. It is an 11000-series scope and accepts up to three 11000-series plug-ins. The CRT is a color touchscreen operating in raster mode. The Tektronix DSA 601 is similar to the DSA 602.
A detailed service manual with schematics is not known to exist. The published service manual is here: