That is one fine example of General Electric's "Coaxial" atomic age sets. The 9"x21" speaker and the RF remote are notable and unique features.
The remote control unit looks and operates similar to a garage door opener. Maybe some one has a memory of these receiving stray signals and coming on, changing channels, etc.
The CRT looks fairly good. I had a 21C3585 and now have the 21C3580 pictured below. The CRTs were soft on both.
I have the complete factory manual for this, PM me if interested.
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