Quote Originally Posted by DIYSwede View Post
Sorry, Rick - but I just can't get heads or tails outta that sentence, but isn't that firstly a 100.208 MΩ resistor?
And then being "negative" also - "a resistor with a negative resistance" - hence simply a DC-to-light linear amp?

Reminds me of my DIY audio design years where I and some of my co-dependants kidded:
"just design an audio interconnect cable with a negative resistance, infinite input impedance and zero ohm source impedance,
no inductive or capacitive reactance, and we'll get rid of all those heavy, ugly amps entirely"...
It was a -100.208K resistor. Put it in parallel with a +100.208K resistor and you get an open circuit:

Rtotal = (R1 x R2)/(R1 + R2) = (100.208K x [-100.208K])/(100.208K + [-100.208K) = (-10000K/0) = infinite which is an open circuit.

The resistor was accurate to +/- 20 parts per million per year and took up an 8 x 11 circuit board. The cost was around $10K back in the 1980's. It more than paid for itself. Oh, and it could survive an indirect lightning strike yet operate from +200V to -200V.

Yes, negative resistor are real and useful. In grad school I made negative capacitors, inductors, and even negative diodes for my Master's project. How does that bend your mind?

For those EE's out there, I once built an audio circuit with a driving point impedance that formed a circle as you went from 200 Hz to 3200 Hz. It used 3 transistors and was used in an analog phone connection to join three phone lines.

Rick