Disable schedule and updates of schedules?

So I want to manually record shows with Media Center. I am recording
on channel 4 because my USB tuner only has that input....which is
fine. My Media Center schedule has shows starting on channel 4 every
half hour. Sometimes my manual recordings go over the half hour mark
and Media Center thinks the show is over so it stops the record. I do
not want the schedule to control anything for me as I am recording off
my external DVR which has the show and I want to start and end
recordings totally manually.

How do I erase the schedule and stop it from updating as I have no use
for it at all?

Thanks