User's Manual

Innovator CU5-1800BTD/BRD ATSC Transmitter/ System Set Up Procedure
Regenerative Translator
Instruction Manual, Rev. 0 62
screen of the LCD display mounted on the Driver Tray. Disconnect the load or the
antenna connected to the system. In the Amplifier Tray, on the Amplifier Control
Board (1309822), adjust the Reflected Calibration Adjustment pot, R26, for a reading
of 10% on the External Amplifier Reflected Forward Power screen of the LCD display
mounted on the Driver Tray. Reconnect the load or the antenna to the system.
Adjust the ALC adjustment Pot, R75, for a reading of 100% on the External Amplifier
Forward Power screen of the LCD display mounted on the Driver Tray. This
completes the reflected power calibration adjustment.
6 MHz
-35 dB
-110 dB
3 MHz
6 MHz
Figure 16: Typical 6 MHz Digital Spectrum
Figure 17: (A3) IF Pre-Corrector Board (1308796)
Linearity Correction Adjustment (Non-Linear Distortions)
As shipped, the system was preset to include amplitude and phase pre-distortion. The
pre-distortion was adjusted to approximately compensate the corresponding
non-linear distortions of the Power Amplifier.
NOTE: Refer to Figure 17. On (A3) the IF Pre-Corrector Board (1308796), check that
the Quadrature Correction enable/disable jumper W7 on J14 and the In Phase
J13
W4
R67 Quad
#1 Threshold
J14
W7
R126 Quad
#2 Threshold
R24, R25 &R26
J4, J5 & J6
R69 Quad
#3 Threshold
R125 Quad
#1 Magnitude
R129 Quad
#2 Magnitude
R128 Quad
#3 Magnitude
R117 In Phase
#2 Magnitude
R110 In Phase
#2 Threshold
R109 In Phase
#1 Threshold
R114 In Phase
#1 Magnitude