This guy beat me to what I was gonna say. Any more details on exactly what you are trying to do? I see more and more issues with getting answers to posts around here because the OP is trying to "Simplify" the explanation thinking they are making it easier to answer...Do you have any idea what voltage range the clock will run from?
If it was designed for 1.5 volt alkaline cells, it may be able to run from 1.2 volts directly, since alkaline voltages run down past 1.2 volts as they discharge.
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