User's Manual

Digital UHF Transmitter Chapter 2, System Description and
Customer Remote Connections
DT835A, Rev. 1 2-6
Table 2-6: UHF Exciter Tray Samples
SAMPLE DESCRIPTION
f(s) A sample of the channel oscillator output taken from
the sample jack of the PLL board
Exciter O/P An output power sample of the exciter taken from the
UHF upconverter board
2.1.9 Variable Phase/Gain Trays
Table 2-7: Variable Phase/Gain Tray Meters
METER FUNCTION
Switch (S1), meter Selects the desired % Power or the ALC voltage
reading
% Output Power Displays the % Output Power of the amplifier array
(100%=+15 dBm 8- VSB digital ≈45%)
ALC Displays the ALC voltage from the UHF exciter that
connects to the amplifier trays in the amplifier array
(.6 - 1 VDC typical)
Table 2-8: Variable Phase/Gain Tray Sample
SAMPLE DESCRIPTION
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
2.1.10 UHF Amplifier Trays
Table 2-9: UHF Amplifier Tray Meters
METER FUNCTION
Meter (A9) Displays power in terms of a percent of the calibrated power
output value. A full-scale reading is 100%, which is equivalent to
300 watts 8-VSB digital. Also reads % Reflected Power, power
supply voltage levels, and AGC voltage levels.
Switch (S2),
meter
Selects the desired % Power or the voltage reading
% Output pwr Displays the % Output Power of the tray (100%=300 watts 8-VSB
digital)
% Refl
(Reflected)
Displays the % Reflected Output Power of the tray (<5% with all
amplifier trays operating as measured on the top scale)
Power supply Displays the power supply voltage, +26.5 VDC, on the middle
scale
AGC voltage Displays the AGC voltage level, +1 - +2 VDC, on the bottom scale