The circuit drawn is almost correct - except that _emitters_ are connected to ground, not collectors. Every 2N3904 is shown upside-down. I thought it employs reverse-active region of BJT operation (like TTL inputs do), but looking at the breadboard implementation I saw emitters grounded, then it all started to make sense. 😉 Perhaps you may eliminate yet another transistor using midpoint of one NAND gate as a source of inverted D input for other one.
Great design, really like the approach! I will have top build this to better understand it. Thanks for sharing!
The circuit drawn is almost correct - except that _emitters_ are connected to ground, not collectors. Every 2N3904 is shown upside-down. I thought it employs reverse-active region of BJT operation (like TTL inputs do), but looking at the breadboard implementation I saw emitters grounded, then it all started to make sense. 😉
Perhaps you may eliminate yet another transistor using midpoint of one NAND gate as a source of inverted D input for other one.
Nice video man! Reminds me a bit of Ben Eater’s breadboard computer videos, but seeing blocks made with just transistors is really cool! Keep it up!
Thanks! Ben Eater taught me a lot about computer architecture. I’d figured I try to make it with only transistors since he did it with logic gates.