The model exhibited here is a Channel Track 2 (serial number 14), which boasted 400 control channels and supported two monitors.  It ran on a 2.5 Mhz Z-80A processor and used only 48K of DRAM. This unit was installed in the showroom at the MGM Grand in Las Vegas. It remained in use there for over a decade, even surviving a fire in 1980. Around 1992, the console was retired and sent back to ETC, where it has lived ever since. When the console arrived, it still had the disk from Liberace’s show in one of its two 8″ floppy drives.
From the ETC Monthly Museum blog, January 2017

Channel Track 2
From ETC Museum Collection
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Channel Track 2 close-up
From ETC Museum Collection
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Channel Track 2 PCB
From ETC Museum Collection
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