Signal Level

The measurement of the signal level sometimes referred to as channel power, delivered to the input of the receiver will be the initial easy check on the suitability of the installation. The levels recommended below have allowances to cater for the requirements of reception in Band III, IV and V in most environments experienced in city and rural locations.

With the experience in analogue reception of 66dBµV and C/ N >45dB as an aim for a successful analogue installation the equivalent for digital TV reception is 66dBµV and SNR >32dB as a rule of thumb for a successful digital installation. For satellite installation the parameters are 63dBµV and MER>12B.

The signal level required at the input of any active headend equipment or amplifier shall be no less than 75dBµV and the recommended output level or launch level should be no higher then 105dBµV.

DTTB is not a solution to very low-level poor analogue reception. Since the Digital service is transmitted 6dB below the analogue, low analogue levels would result in lower digital level and unacceptable levels for amplification. Digital reception is ideal for improving poor analogue reception such as ghosting and general interferences. To achieve this however, the Digital signal level needs to be maintained at a reasonable level at all times.

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