Assembly Instructions

835A 4 kW, 5 kW or 6 kW UHF Transmitter Meters, Switches, Indicators and Samples
Name
Function
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UHF Amplifier Trays- Continued
Status Indicators
Overdrive (DS2 Red) Indicates that the level of the drive to the output amplifiers is too high. The
protection circuit will limit drive to the set threshold. The Fault is generated on
the Amplifier Control Board.
VSWR Cutback (DS1 Red) Indicates that Reflected Power Level of the Tray has increased above 50% which
will automatically cutback the Output Power Level to 50 %. The Fault is
generated on the Amplifier Control Board.
Overtemperature (DS3 Red) Indicates that the temperature of (A5-A6-A3 & A5-A6-A4) one or both of two
Thermal Switches mounted on the heatsink assembly for the output amplifiers is
above 175° F. When this Fault occurs the Enable to the Switching Power Supply
in the effected Amplifier Tray is removed immediately.
Sample
Module O/P (0 dBm) A Sample of the Combined Output of the four Dual Stage Amplifier Boards
taken from the Dual Peak Detector Board.
Variable Phase/Gain Trays
Meters
Switch (S1), Meter Selects the desired % Power or the ALC Voltage reading.
% Output Power Reads the % Output Power of the Tray. (100% = +23 dBm pk of Sync + Aural)
ALC Reads the ALC Voltage, from the UHF Exciter, which connects to the Amplifier
Trays.
Sample
Output (J4), (0 dBm) A front panel Sample of the RF Output of the Phase/Gain Tray which connects to
the Amplifier Array, taken from the Variable Gain/Phase Board.