6 Feb
2019
6 Feb
'19
10:37 p.m.
4116 datasheet specs 2mS, my calcs give a refresh
period of 1.5mS, the 14.5uS from the manual would give 1.86 mS, 7% shy of 2.
The schematic specs 1% resistors, and the parts list does appear to spec a high-tolerance
"1%200PPM" cap.
Although there are the internal voltage divider Rs in the 555 which are also critical for
the timing and everything is 40+ years old.
Idle speculation at my distance, we'll see what Fritz observes.
Brent: 11.8us, 6.4us position
Manual: 14.5us, 6.0us positive
Actual: 15.2us, 8.5us positive
So yeah, a little pokey there...