Harris Platinum HT EL 2000LS, Technical Manual

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5.7.3.1
Transmitter Visual Forward Power Calibration
a. Adjust the transmitter vision output power to the correct
average value calculated using information in paragraph
5.6.2.
b. Connect a DVM to the Interface Logic Board 1A7 TP8
(Visual Forward Power).
c. Adjust R39 (VIS FWD CAL) for 2.6 V at TP8.
d. Select VIS FWD on the Exciter Meter.
e. On the Exciter Meter Adjust R5 (VIS FWD CAL) for a
numeric reading of 2000.
f. Adjust R101 (VIS FWD CAL) for full scale reading on
the Bar Graph.
5.7.3.2 Transmitter Visual Reflected Power Calibration
a. Connect the visual reflected power sample cable to the
forward power port of the visual output directional cou-
pler.
b. Connect a DVM to the Interface Logic Board 1A7 TP7
(Visual Reflected Power).
c. Adjust R13 (VIS REF CAL) for 1.46 V at TP7. This is 5
Db less for the coupler ratio.
d. Select VIS REF on the Exciter Meter.
e. Adjust R6 (VIS REF CAL) for a numeric reading of 2000.
f. Adjust R99 (VIS REF CAL) for full scale reading on the
Bar Graph.
5.7.3.3
Transmitter Aural Forward Power Calibration
a. Adjust the transmitter aural RF output to 200 watts CW.
b. Connect a DVM to the Interface Logic Board 1A7 TP6
(Aural Forward Power).
c. Adjust R16 (AUR FWD CAL) for 2.6 V at TP6.
d. Select Aural FWD on the Exciter Meter.
e. On the Exciter Meter Adjust R7 (AUR FWD CAL) for a
numeric reading of 200.0 watts.
f. Adjust R100 (AUR FWD CAL) for full scale reading on
the Bar Graph.
5.7.3.4 Transmitter Aural Reflected Power Calibration
a. Connect the aural reflected power sample cable to the
forward power port of the aural output directional coupler.
b. Connect a DVM to the Interface Logic Board 1A7 TP5
(Aural Reflected Power).
c. Adjust R23 (AUR REF CAL) for 1.3 V at TP5. This is 6
Db less for the coupler ratio.
d. Select AURAL REF on the Exciter Meter.
e. Adjust R8 (AUR REF CAL) for a numeric reading of
200.0 watts.
f. Adjust R98 (AUR REF CAL) for full scale reading on the
Bar Graph.
5.7.4
VSWR Fault And Foldback Adjustments
5.7.4.1
Initial Setup for Adjustment
a. Start with the transmitter OFF.
b. Reduce Visual and Aural Exciter output to zero.
c. Place JP1 and JP2 in 2-3 position to disable foldback.
5.7.4.2
Visual High VSWR Adjustment
a. Move the coax cable 1A7P7 from 1A7J7 to 1A7J8.
b. Select the VIS REF meter position.
c. Turn on the transmitter and slowly increase visual output
power until the VIS REF meter reads 200 watts. This is
the level for a VSWR of 2.0:1.
d. Adjust R69 (VIS HIGH VSWR), on 1A7 (Interface logic
Board), until the HIGH VSWR light on the Exciter just
lights and the voltage on 1A7 TP11 changes from 5V to
0V.
5.7.4.3
Visual VSWR Foldback Adjustment
a. Reduce the visual power to zero.
b. Move the jumper JP1 to 1-2 position to enable the fold-
back function.
c. Slowly increase the visual output power until the VIS REF
meter reads 20 watts. This is the level for a VSWR of 1.2:1.
d. Adjust R48 (VIS FB SET), on 1A7 (Interface Logic
Board), until the FOLDBACK ACTIVE light on the Ex-
citer just lights.
e. Restore the visual sample coaxes to the proper location.
5.7.4.4 AURAL HIGH VSWR Adjustment
a. Move the coax cable 1A7P9 from 1A7J9 to 1A7J10.
b. Select the AURAL REF meter position.
c. Turn on the transmitter and slowly increase Aural output
power until the AURAL REF meter reads 20 watts. This
is the level for a VSWR of 2.0:1.
d. Adjust R74 (AUR HIGH VSWR), on 1A7 (Interface logic
Board), until the HIGH VSWR light on the Exciter just
lights and the voltage on 1A7 TP12 changes from 5 V to
0.
5.7.4.5 Aural VSWR Foldback Adjustment
a. Reduce the aural power to zero.
b. Move the jumper JP2 to 1-2 position to enable the fold-
back function.
c. Slowly increase the visual output power until the AURAL
REF meter reads 5.5 watts. This is the level for a VSWR
of 1.4:1.
d. Adjust R53 (AUR FB SET), on 1A7 (Interface Logic
Board), until the FOLDBACK ACTIVE light on the Ex-
citer just lights.
e. Restore the visual sample coaxes to the proper location.
5.8
Transmitter AGC Adjustment
5.8.1
Visual AGC:
a. Preset the following:
1. JP12 to position 2-3 AGC out
2. JP13 to positions 1-2 and 3-4 3 dB Attenuator out
3. JP14 to positions 1-2 and 3-4 2 dB Attenuator out
b. Turn on the transmitter ON and increase the visual drive
for 2000 watts peak of sync with a black picture.
Platinum™ Series
5-4 888-2457-001
WARNING: Disconnect primary power prior to servicing.