Assembly Instructions Chapter 4

10-kW UHF Transmitter with Chapter 4, Circuit
Feedforward Drive Descriptions
840A, Rev. 0 4-31
enables the tube hour counter that is
connected through connector J7-1 and
J7-5.
Operational Voltages
The +12 VDC needed to operate the
board enters at J1, pin 3, and is filtered
by L1, C1, and C4 before it is fed to the
rest of the board.
The -12 VDC needed to operate the
board enters at J1, pin 5, and is filtered
by L2 and C21 and C22 before being fed
to the rest of the board.
The +5 VDC is supplied by 5-VDC
regulator U1 and is filtered by C1 and C3
before being fed to the rest of the board.
C3 is used to maintain power on the +5-
VDC line for short duration power losses.
DIP Switch Configuration
The DIP switch configurations for the
board are shown in Table 4-2.
Table 4-2. DIP Switch Configurations for the Filament Power Supply Control Board
POSITION FUNCTION
SW1-1 Not connected
SW1-2
Accelerate timers: When set high, the ramp-up, ramp-down, and blower
delay timers operate four times faster
SW1-3
Ten-minute by-pass: When set high, and all other DIP switch settings are
low except SW1-5, the ten-minute warm-up is skipped
SW1-4
SCADA: When set high, SCADA interrupts will be processed
(future development)
SW1-5
Set DAC 0.0 VDC: When in the Standby mode, setting this switch high
causes the DAC to output 0.0 VDC
SW1-6
Set DAC 4.625 VDC: When in the Standby mode, setting this switch high
causes the DAC to output 4.625 VDC
SW1-7
Set DAC 5.0 VDC: When in the Standby mode, setting this switch high
causes the DAC to output 5.0 VDC
SW1-8 Micro reset: When this is set high, the microcontroller is held in reset
4.2.5 Metering Control Panel
The (A7) metering control panel (1293-
1308) contains three meters: one for
voltages, one for currents, and one for
power output. The voltage meter displays
the plate, screen, bias, and filament
voltages that are applied to the tube. The
current meter displays the plate, screen,
and grid currents that are produced by
the tube. The power meter displays the
% Aural Output power, % Visual Output
power, and % Reflected Output power of
the 10-kW amplifier. The metering
control panel also provides the system
control functions for the 10-kW
transmitter.
The metering control panel consists of
(A1) the control logic board (1137-1402),
(A7) the transmitter control board (1137-
1003), (A2 and A3) two differential buffer
boards (1008-1017), (A4) fault sensing
board, diacrode (1293-1307), (A5) fault
sensing board, inverting (1016-1401),
and (A6) the fault sensing board, dual
polarity (1016-1402). The panel also has
(M1) a front panel voltage meter with
(S1) the meter control switch; (M2) a
front panel current meter with (S2) the
meter control switch and (S3) the meter
reverse switch; and (M3) a front panel
power meter with (S4) the meter control
switch. The panel has (S5) the
Operate/Standby switch, (S6) the
Auto/Manual Mode Select switch, (S7)
the High-Voltage Enable/Disable switch,