Sony KD-50X75

There's digital input port.

Is this for "MyTV" thingy?

If it is, do I still need MyTV decoder? Or just plug in antenna?

Any in-house antenna to recommend, since this is apartment and I will definitely not be allowed to install "rooftop".

Writing my observation.

Sony KD-50X75
HDMI 1 - Astro Ultrabox (satellite-mode)
HDMI 2 - free
HDMI 3 - Sony HT-S20R 5.1 soundbar

Inside TV's HDMI CEC Settings
CEC: on
Device auto power off: on
TV auto power on: on

Observation 1:
Switching off the TV will cause the soundbar to enter Standby.

Observation 2:
If Astro Ultrabox is state:off before TV is switched on again, the soundbar will awaken almost immediately and TV will autoswitch from using internal speaker to using the soundbar.

Observation 3:
If Astro is state:on before the TV is switched on again, the soundbar will awakan after a longer period of time. TV will never be able to use the soundbar even if TV manually selected to use it; won't output a sound.

Thank you for that pin map.

I intended to cut it off, but without proper cutting tool, i ended up using sewing pin to press the pin into its valley (not pushed back deep into the plug in case it interconnect with any exposed parts inside), then press few layers of "fine" strands of cellophane tape over it to hold and to fashion some sort of insulation.

problem solved.