Broadcast Electronics FM-5T, User Manual

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2-7
WARNING: DISCONNECT POWER PRIOR TO SERVICING
2-58. Wait approximately 15 seconds. Note the time and depress the HIGH VOLTAGE ON
switch/indicator.
2-59. Again note the time when the plate contactor energizes.
2-60. Refer to Figure 2-1 and select the warm-up feature by operating customer adjustment
function switch SW1 to position 0.
2-61. Refer to Figure 2-1 and use up/down switch S2 to increase or decrease the time delay.
Check the adjustment by repeating the procedure. The control is factory set for 10 sec
onds.
2-62.
COOL-DOWN ADJUSTMENT.
The cool-down adjustment controls the blower run-down
interval after the filament voltage is off. The cool-down time can be adjusted from 30 sec
onds to 4.5 minutes. A minimum interval is preset so that incorrect adjustment cannot
damage the PA tube. To adjust the cool down time, proceed as follows.
2-63. Required Equipment. The following equipment is required to adjust cool down time.
A. Wristwatch with seconds hand or stopwatch function.
2-64. Procedure. To adjust the cool-down time, proceed as follows.
2-65. Apply power and operate the transmitter.
2-66. Simultaneously depress the FILAMENT OFF switch and note the time.
2-67. Again note the time when the blower halts operation.
2-68. Refer to Figure 2-1 and select the cool-down feature by operating customer adjustment
function switch SW1 to position 3.
2-69. Refer to Figure 2-1 and use up/down switch S2 to increase or decrease the blower run-
down interval. Check the adjustment by repeating the procedure. The control is factory
set for 30 seconds. Each click of S2 is equal to 1 second.
2-70.
RECYCLE ADJUSTMENT.
The recycle adjustment controls the amount of time the trans
mitter will remain deenergized to allow an overload to dissipate. The recycle time can be
adjusted from 100 milliseconds to 15 seconds. The factory default is 2 seconds. To adjust
the recycle time, proceed as follows.
2-71. Required Equipment. The following equipment is required to adjust cool down time.
A. Wristwatch with seconds hand or stopwatch function.
2-72. Procedure. To adjust the recycle time, proceed as follows.
2-73. Apply power and operate the transmitter.
2-74. Simulate a screen or plate overload using the OUTPUT LOADING control and note the
time when the transmitter attempts to return to operation.
2-75. Refer to Figure 2-1 and select the recycle feature by operating customer adjustment func
tion switch SW1 to position 2.
2-76. Refer to Figure 2-1 and use up/down switch S2 to increase or decrease the recycle time.
Check the adjustment by repeating the procedure. The control is factory set for 2 seconds.
Each click of S2 is equal to 1 second.
2-77.
WARM-UP DEFEAT ADJUSTMENT.
The warm-up defeat adjustment controls the length
of the interval the filaments can be off before initiating a new filament warm-up cycle.
The warm-up defeat time can be adjusted from 1 second to 15 seconds. A 3 second delay is
preset so that momentary power fluctuations will not initiate a new filament warm-up cy
cle. To adjust the warm-up defeat time, proceed as follows.