Check the recording source, not just the viewing screen
A television can be switched on while the computer or NAS running Plex Media Server is asleep. For a scheduled tuner recording, the source server’s availability matters. Note where the server actually runs and whether that system, its storage or its network interface enters a power-saving state during the scheduled period.
Use the DVR-specific explanation
Plex’s DVR FAQ explicitly says a scheduled recording will not wake the server from sleep. It advises ensuring the system does not sleep or hibernate and that disks and network interfaces remain available. The server also needs its configured compatible tuner and antenna arrangement. A schedule entry alone does not prove those components will be ready when the broadcast starts.
Prepare a short known recording
For example, an administrator can review the source computer’s current power policy, then schedule an authorised short broadcast while the system is deliberately available. Inspect the resulting recording and schedule status. Do not infer that a television’s own wake feature applies to a separate NAS, and do not leave a device running permanently without considering its ordinary operating requirements. If a recording fails, record the server’s power state, broadcast time and tuner status. Those observations distinguish this condition from a conflicting schedule, missing guide entry or playback problem with an already created file.
Questions, answered
Will the recording schedule itself wake the computer or NAS?
Plex says it will not; the server system must be available at the scheduled time.