DTC Communications Inc. PD2TX100S ユーザーズマニュアル
DTC COMMUNICATIONS, INC.
11
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.
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.
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.
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. Tthe 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.
modes of 1.25 or 2.5 MHz. Tthe 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.
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%.
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%.