Data Sheet Chapter 5

10-kW UHF Transmitter with Chapter 5, Detailed Alignment Procedures
Feedforward Drive
840A, Rev. 0 5-25
filament power supply; it should be
1.5 volts.
7. Verify that J3-1 remains at 0 volts
and DS1 blinks at a 1-Hz rate while
the following actions are performed:
• Switch on SW1-3 and turn on
SW1-5, SW1-6, and SW1-7
individually (no time limit).
• Connect +12 volts to TB1-5 for
less than 5 seconds.
• Turn off the external +/-12-volt
power supply for less than 5
seconds.
• Remove J6 from the controller
board for less than 5 seconds.
• Ground TB1-6 several times and
then leave it unconnected.
• Turn off the 220 VAC at TB2-1
and TB2-2 for less than 5
seconds.
8. After 10 minutes, DS1 should begin
blinking at a 2-Hz rate. This signals
that the 10-minute time-out period
has successfully been completed. At
this point, with SW1-3 on, switch
SW1-5 on. J3-1 should be 0 volts.
Switch SW1-5 off and SW1-6 on; J3-
1 should be 4.625 volts. Switch SW1-
6 off and SW1-7 on; J3-1 should be
5.0 volts. If necessary, adjust R6 on
the controller board until a reading of
5.0 volts is obtained.
9. Ground TB1-6 to simulate a filament-
on command and note the time. The
voltage at TB1-7 should be 0 volts;
220 VAC should now be present at
TB2-7 and TB2-8; and DS1 should be
blinking at a 4-Hz rate. The voltage at
J3-1 should increase to 4.625 volts
over a three-minute time frame.
During this ramp-up phase, the
following conditions should not cause
DS1 to stop blinking at its 4-Hz rate
or the ramp-up to discontinue:
• Connecting TB1-5 to +12 volts for
less than 5 seconds
• Turning off the external +/-12-
volt power supply for less than 5
seconds
• Removing J6 from the controller
board for less than 5 seconds
• Turning off the 220 VAC at TB2-1
and TB2-2 for less than 5 seconds
• Switching SW1-5, SW1-6, and
SW1-7 on and off individually (no
time limit)
Note: Leaving any of the above
conditions on for longer than 5
seconds should cause the filament
power supply to revert back to the
10-minute warm up cycle (J3-1 at 0
volts).
10. Remove the ground from TB1-6. The
voltage at J3-1 should begin to
decrease. Re-ground TB1-6. This
should cause J3-1 to start ramping
back up. Once J3-1 is at 4.625 volts
(5.2 volts across the load resistor),
DS1 should not be blinking. Perform
all of the tasks in step 10 and verify
that J3-1 remains at 4.625 volts. It
should be noted once again that
performing these tasks for longer
than 5 seconds should cause the
voltage at J3-1 to again return to 0
volts for 10 minutes.
11. Remove the ground from TB1-6. The
5 volts at J3-1 should start to ramp
down. Re-ground TB1-6. The voltage
at J3-1 should start to ramp back up.
Remove the ground again. J3-1
should return to 0 volts over a 3-
minute time frame; TB1-7 should
remain at 0 volts; TB2-7 and TB2-8
should not have 220 VAC present;
and DS1 should be blinking at a 4-Hz
rate. Perform the same tasks as in
step 10 and verify that they have no
effect on the ramp-down cycle.
Taking any more than 5 seconds for