1) From that schem, if I remove 1x Input and either Invert the output or take the Q Output from the joined Emitters (hmmm - not so sure about that option now...) - does that give me a 2x Input OR?
2) Is a 3x Input NOR the same as an XNOR? i.e. If I invert the output of that schem I get a 3x Input XOR from that XNOR? The truth tables suggest not - but I'm asking anyway.
If not! Anyone got any pointers to a 2x In OR and a 3x In XOR using RTL?