Well, I have already chosen the 4059 to avoid too many IC's. First I wanted to make a normal modulus divider, but since there is the 4059 I used that
Meanwhile I did some calculations:
Assuming one uses a 32768Hz standard clock oscillator, we must do divisions like to following (division no more than 21327, because that is the max. of the 4059:
division by 20693
division by 18037
division by 14
After that and having an accurate oscillator, we have a drift of 0.14 seconds during one orbit of moon and that is negligible.
But the lunation (the time between two successive new moons) varies for about +/- 0.25 days (-> 6 hours), so the display might be not very accurate for single phases, but it will be accurate over time.
Well, doing that without a microcontroller requires at least a number of 6 IC's (3*4059; plus a counter and some to display the phase)
BTW, why must the phase-display run from a battery ???
If that is required, you won't be able to avoid a low-power uC...
Greetings,
Hannes.