Some Channels Are Blank; Poor Reception Or Poor Picture Quality With Digital Broadcasts - Sony XBR-65X900 Instruction Manual

Make sure that the antenna is connected using a high quality 75-ohm coaxial cable.
Keep the antenna cable away from other connecting cables.
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Check these things first to troubleshoot your TV reception.
[110] Troubleshooting | Broadcast reception

Some channels are blank.

The channel is for scrambled/subscription service only. Subscribe to a pay TV service.
The channel is used only for data (no picture or sound).
Contact the broadcaster for transmission details.
Related topics
Check these things first to troubleshoot your TV reception.
[111] Troubleshooting | Broadcast reception
Poor reception or poor picture quality with digital
broadcasts.
Change the position, direction and angle of the terrestrial television antenna to maximize the
antenna signal level. Make sure that the direction of the antenna is not changed unintentionally
(such as by wind).
If you are using a TV signal booster, adjust its signal gain.
If equipment (such as a TV signal distributor) is connected between the antenna and the TV, it may
affect the TV reception. Directly connect the antenna and the TV to check if the reception is
improved.
Related topics
Check these things first to troubleshoot your TV reception.
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