A quick Google search seems to indicate that most manufacturers do not have universal codes for Olevia TVs. Some people reported limited success (power and volume control) using codes for Philips televisions. Otherwise you'll have to use the scan codes function of the remote to try every stored code until one works, or if the DVR remote is a "learning" remote you can use the TV's remote to teach the DVR remote how to control the TV. I didn't see anything in the DVR-3 remote's manual indicating whether or not it is a learning remote, so I suspect that it doesn't have that ability.