So I'm making a one shot out of two 74HC14, the first gives a nice sharp edge to drive the cap. (~47pF) into the second. (which has R and diode to positive rail. I think R_min is 500 ohm. Well, that's more delay than I thought it was, (eating crow.. "mmm good crow")
I've got a faster comparator to try on the front end, maybe I should do that first.?
George H.