Scheduler time starts at 7:30 am?

Is there any way of setting the scheduler to start at 7.30am and finish at 5.30pm
At the moment i have it set from 7 till 6 but would like to get it down precisely .
The admin section in Joomla doesnt seem to like 7.5 etc

Unfortunately this is not possible. Scale of scheduler must start from some hour value , and can’t start from custom time.