Look at the cable box. Is it showing a number or is the screen blank? If it's showing a number, it's probably already on. Get the remote control for the cable box. Sometimes it is different than the one for the TV. On this Comcast remote, you would press the "All On" button. If this remote controls both your TV and your cable box, it will turn both of them on at the same time. If it only controls your cable box, proceed to the next step. If the TV doesn't turn on, something might be wrong with the remote. Check the batteries or, if it's a universal remote, press the "TV" button and try the power button again. If the TV turns on but you're not seeing a channel (just a blue screen, or the phrase "no signal"):  Check that the cable box is indeed on. Check that the TV is on the correct channel to receive a signal from the cable box. In many cases, this is channel "zero".

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Write a summary of the previous text in Indonesian:
Pastikan kotak penerima (cable box) menyala. Tekan tombol daya pada Pengendali TV.