1ms-Takt korrekt?

Is 1ms puls chain “1ms-Takt” triggert by negative edge of supply current's phase correct?
Schaltung ☛

Unordered List ItemPositiv puls length is obvoiusly exact 1 ms as targeded. But: How is the reptetion rate? “Low” and “High”s are not of equal length! But we espected 20 pulses inside a 50Hz (20ms) interval … If here a complete periode with “01” is determed to be 1,6ms this equals a rate of 12,5 pulses / 20ms.
Unordered List ItemWhy is digital output not presenting a flattop at high level? The frequenzzy defining elements are a capacity and a restistor with the resulting RC product. The given resistor at this borad is low ohmic: by this higher charge and dischrage currents flow in one periode, Chosing a higher restistor but an lower capacity will lowerd the currents and might result in a more flat top.