How to selectively enable TM by time...

Dear Community,

I'm preparing to upgrade several machines on my network to Mountain Lion. I have encountered an issue since moving to Snow Leopard where TimeMachine is very sensitive to writes to targets that are busy. TM tends to corrupt its data in these situations.

My solution has been to modify TM's schedule with utilities like "Time Machine Scheduler" to selectively enable TM to avoid backing up when the TM target NAS is busy (doing RAID resyncs, etc.) This has worked passably well.

I would, however, like to find a method that does not require 3rd party tools. So my question is this: is there a way to turn off a utility such as TimeMachine for a particular time period, and leave it on and running normally for the rest of the time? I'd like to disable it from 3AM until noon on Mondays and Tuesdays and have it run normally otherwise.

It's a bummer that more detailed scheduling isn't available in the tool itself, but this question is more general than TimeMachine.

Thanks in advance,

H.