The skyles board intrigues me…… your PET has 2114 replacement boards as mentioned above (replacing system ram) but this board is a sram board also…. With what looks like a toolkit rom (perhaps)… all mounted off the expansion port … I wonder if this is SRAM for $a000/$9000 memory locations assuming the toolkit occupies $b000Here are some better pictures. Third picture is of the top small daughter board.
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