Check for correct sync ratio at the PA output. Connect a high
impedance voltmeter to TP-1 on the Main controller 1A3 of the PA
cabinet energized and adjust R-79 for the value in the table below:
Model TP-1 voltage
HT1, HT2, HT5 1.8 V
HT10, HT15 2.5 V
The display panel should now indicate rated peak of sync power
on the visual meter page.
Now connect the forward cable at J-7 to J-8 and adjust reflected
calibrate control R-74 to the same voltage as above.
When finished, restore cables to their original positions.
5.13.2
HT20, HT30, HT60 Transmitters
For these transmitters, energize one visual PA cabinet at a time,
and apply blanking and sync test signal to the exciter. Be sure no
“SET-UP” is used. Use external metering at the combined port
and adjust the combined average power to the value listed in the
table below:
B/PAL
Model M/NTSC B/SECAM
HT20 2.98 kW 2.84 kW
HT30 4.46 kW 4.26 kW
HT60 2.23 kW 2.13 kW
Check for correct sync ratio at the PA output. Connect a high
impedance voltmeter to TP-3 on the slave controller of the PA
cabinetenergizedand adjust R-60for2.5Volts. Thedisplaypanel
should nowindicate the rated cabinet peak of sync power(10 kW
for HT20, 15 kW for HT30 and HT60) on the appropriate visual
meter page. Connect the forward cable at J-7 to J-8 and adjust
reflected calibrate control R-74 for 2.5 Volts at TP-4.
Restore the cables to the original configuration, then repeat the
procedure for the remaining cabinet(s).
5.13.3
HT45 Transmitters
For 45 kW transmitters, energize one visual PA cabinet at a time.
Apply blanking and sync test signal to the exciter. Be sure no
“SET-UP” is used. Using external metering at the combined port,
adjust the transmitter output power to the values of combined
averagepowerindicatedin thecorrecttablebelow. Usethetablethat
corresponds to your system (M/NTSC, B/PAL, or B/SECAM).
Check for correct sync ratio at the PA cabinet output.
Connect a high impedance voltmeter to TP-3 on the slavecontroller
and adjust R-60 for 2.5 Volts. The display panel should indicate 15
kWontheappropriatevisualmeterpage.Connecttheforwardcable
at J-7 to J-8 and adjust reflect calibrate control R-74 for 2.5 Volts at
TP-4. Restore cables to normal configuration.
Repeat the above procedure for each cabinet.
Combined Average Power Out Versus PA Cabinet Combi-
nations
M/NTSC Systems
Cabinets ON
Average Combined Power Output
ABC
15 0 0 2.98
0 15 0 2.98
0 0 15 2.98
15 15 0 11.9
15 0 15 11.9
0 15 15 11.9
15 15 15 26.8
HT30LS/H
T30HS
FORWARD REFLECTED
VISUAL PA
(INDIVIDUAL CABINETS AS
REQUIRED)
R60 @TP3
(VISUAL PA SLAVE CONTROLLER)
R74 @TP4
(VISUAL PA SLAVE
CONTROLLER)
VISUAL REJECT POWER R95 @ TP5
MAIN CONTROLLER)
COMBINED VISUAL POWER R79 @TP1
(MAIN CONTROLLER)
R87 @TP3
MAIN CONTROLLER)
AURAL POWER R83 @TP2
(MAIN CONTROLLER)
R91 @TP4
(MAIN CONTROLLER)
VISUAL DRIVE POWER R75 VISUAL DRIVE A @TP5
(AURAL PA SLAVE CONTROLLER)
OR
R76 VISUAL DRIVE B @TP6
(AURAL PA SLAVE CONTROLLER)
AURAL CHAIN POWER R60 CHAIN A @TP3
(AURAL PA SLAVE CONTROLLER)
R74 CHAIN B @TP4
(AURAL PA SLAVE CONTROLLER)
Table 5-4. Peak Detector Power Calibration
Section V - Maintenace
Rev. B: 1/11/1999 888-2365-001 5-7
WARNING: Disconnect primary power prior to servicing.
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