My 2015 LG TV has built in decoder. I just installed MYTV today. 5 elements antenna is mounted high on the rooftop. As per Google map, direct line distance to KL Tower is 11km. Full HD Channels are crystal clear and I'm able to receive Dolby Digital audio but it's only 2 channel s. I hope the stations will transmit in Dolby Digital 5.1 to unlock the full potential of the hardware. Occasionally though, there's a 1 second mute in audio. Not sure if anyone experience this? Subtitles for a movie I watched appears clipped. I've not used it enough to conclude how good it is but first impression is quite good. Probably there  are still some technical glitches in the transmission for them to iron out I'm not sure..

why RTM not getting more tv channels (temporary) to broadcast those olympics channels that are available at their website?

Maybe.... Their broadcast rights doesn't permit them to show ALL matches live?

Or RTM doesn't spend as much money on streaming servers bandwidth to provide as much as 13 channels on their website?

It's free. What do you expect lol... 😅