I guess if I use it correctly a transistor can look like a variable resistance in that it has controllable voltage and current.
That agreed, if a transistor can be a range of resistors, then transistors seem more versatile, but then if in any one place what I need is a resistor, a resistor might be a good choice.
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Sorry, didn't really get what you were doing with the circuit above.
A bridge will balance when., well, in balance. That makes bridges truely nifty, I entirely agree, but not sure I'd call it a computer.
Semantics aside, I've had a lot of fun with analogue circuits. If you'd like to explain a little more, we might be able to share the wonder.