User's Manual

PROGRAMMING

Transmitter Control Application

Output Frequency (MHz)

The Output Frequency setting allows selection of TX output frequency in increments of 0.250 MHz within

the allowed tuning range of the unit. If the unit is set to a frequency that is not an integer multiple of 0.25

MHz, the unit will be automatically set to the closest frequency that is an integer multiple of 0.25MHz.

Modulation Bandwidth

Modulation Bandwidth is the actual channel bandwidth that the wireless video link will occupy. The DVB-T

compliant mode requires a bandwidth setting of 6, 7 or 8 MHz. The narrowband mode bandwidth is either

1.25 or 2.5 MHz. Narrower bandwidths increase receiver sensitivity and extend the maximum distance of

the link, however video quality and latency will suffer. Normal default for good quality video is 2.5MHz. The

modulation bandwidth may be set to 1.25 MHz, 2.5 MHz, 6 MHz, 7 MHz, or 8 MHz.

Modulation Output

This control is used to turn ON and OFF the RF output. It must be ON for operation. Turn the transmitter RF

power ON by selecting ON and Apply from the application.

Narrowband FEC

Narrowband FEC sets the forward error correction rate in the narrow bandwidth modes of 1.25 or 2.5

MHz. The two rates are available are 1/3 and 2/3; the normal default setting for good quality video is 2/3.

Changing the FEC rate to 1/3 will extend the receiver sensitivity by 2 to 3 dB at the

expense of degraded video quality and longer latency.

Narrowband Guard Interval

Narrowband guard interval is used in the narrowband modes of 1.25 and 2.5MHz to adjust for varying

multi-path delay conditions. The default is

1/16 however 1/8 can be selected if necessary to deal with extreme multi-path delays on long links.

Selecting 1/8 guard interval could cause a degradation in video quality and latency.

Narrowband Modulation

Narrowband modulation is used in the narrowband modes to select between QPSK and 16QAM

modulation. For best range with good video quality, QPSK is used; 16QAM will give better video quality but

will cut down the link range by

approximately 50%.