>Let the RC time extend the (manual) reset way past the rise-time
>of the power-supply. Start with 10K/10uF and enlarge cap if
>nescessary.
10k/(10uF,22uF,44uF,470uF) - do not help.
>Compare the behavioure of the circuit when shutting off DC vs AC.
No such problem when shutting off DC.
>Does it work properly when shutting off/reconnecting DC?
No.
>Did you tru to use another uC w/o internal reset circuit for test ?.
Didn't eyt.