I am looking and failing to find a topic about building a Not gate using RTL logic, with the addition of a capacitor. The discussion was how the capacitor increased high frequency performance. I think it was Garth who posted a schematic with suggested values.

I want to build it and use scope probes to look at how the capacitor responds to a roughly 1 MHz square wave. I wanted to compare it with the transistor D flip flop on this page: https://www.wellpcb.com/transistor-flip-flop.html

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

A simple way to look at is to consider that where normally, the resistor limits the current that is used to charge the transition region in the transistor and thereby make it conduct, the capacitor provides a brief pulse of current at the rising edge in addition to the current through the resistor.

Neil

@Garth, thanks, that's the topic.

@Neil, yes the capacitor has a low impedance at high frequencies, so it makes the transistor more responsive as well. What I thought was interesting is that in the flip flop circuit it also acts as an edge detector to latch a value only on the rising edge.