A substantial disadvantage of the design of these machines is that because the refresh cycle is commandeered for other purposes, they're built around an assumption of static RAM. As a result, each shipped with only 1kb at launch and expansions beyond 16kb were rare.
PAL/SECAM compatibility was not an issue on these machines as they could only output black-and-white video signals anyway. Maybe that fouled fooled Lord Sinclair into neglecting SECAM on its following machine, the [[ZX Spectrum]].
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