David Butleradded February 16, 2019

Here we go. The Maganox Odyssey was released back in 1972. It was the world's first home game console, based on Ralph Baer's "Brown Box" prototype from the 1960s. It outputs RF over an unusual plug that is neither RCA (like Atari 5200 and Atari 7800) nor coaxial (like most RF modulator/demodulator boxes). I've only seen this on the Odyssey and one pong console. Some TV game switchboxes from the past can accept this connector, but most seem to have the RCA plug. And then the switchbox ends in VHF forks, which i converted to coaxial.
The game cards (1-6 are pictured) do not contain ROM chips, which is why this console is not considered the first cartridge-based game system. The actual first cartridge-based system is the Fairchild Channel F from 1976. The Odyssey game cards rewire the internals of the console to select from built-in games. The games are controlled by paddles, which generally move squares around the screen.
Im still working out how to play the games. Im not sure that it is displaying correctly, as Tennis seems to have two small squares batting a line segment batting a long rectangle back-and-forth. That feels backwards. From what i have read in the manual the game logic seems very primitive, and it appears to be up to the players to decide who wins. It feels a bit like the descriptions of the Cathode Ray Tube Amusement Device from 1947 in that regard.
I have taken photos of the very best pictures that i was able to get on my 4K television and my PVM. I had trouble getting a clear signal. The VCRs that i typically use for my View-Master Interactive Vision and my Gakken Compact-Vision TV Boy did not do a very good job. Thankfully, i had a tiny color TV with RF in, composite video out, and a better RF demodulator. That got me clearer visuals. Unfortunately, the overlays dont work very well for the 4K TV.