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Building a vacuum tube computer
Having 32 (31) registers, this means that a refresh will be issued each 256us. To be on the safe side, the capacitor should keep its charge much longer than that. Testing with both EAA91 (ideal diode) and some semiconductors: Diode charge hold time Comment EAA91 >500us ideal diode 1N4148 >500us for reference, leakage…