the physical power button on the TV set (not the remote).
TP.SK506S.PB802 is the chassis (mainboard) model number for a cost-effective, "universal" Smart TV platform. Rather than being exclusive to a single manufacturer, this board is mass-produced and then customized via firmware for various brands that sell TVs under their own names. These brands include: tp.sk506s.pb802 firmware
MediaTek/Mstar MSD6681BQHA (Quad-Core)
Because this motherboard is sold to original equipment manufacturers (OEMs), the same internal hardware is deployed under many brand labels. Common retail models running the TP.SK506S.PB802 chassis include: the physical power button on the TV set (not the remote)
Flashing the firmware can resolve several common software-related issues: tp.sk506s.pb802 firmware
Step-by-Step Guide: How to Install TP.SK506S.PB802 Firmware via USB