Harris Platinum HT EL 2000LS, Техническое руководство

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4.6.2
50V SUPPLIES 1A11A1 and 1A11A5
The supplies are rated for 50 volts at 60A’s full load. In a 2kW
transmitter running black picture the current is about 100A’s
which leaves good head room for the supplies. There is one user
adjustment on the back of supply used to set the supply voltage
to 50 volts. The supply has current foldback, temperature fold-
back, and over-voltage protection. If an over-voltage fault
should occur the supply will shut down and remain off until ac
power is removed and reapplied again.
4.6.3
LOGIC SUPPLY 1A11A3
The Logic Supply 1A7A3 is located in the power module
chassis. The linear regulated logic supply pr5V and +/-
12V for the Interface Logic Module 1A3 and AC ON relay
1A11K2. The supply has voltage adjustments on the 1A7A3 PC
boards for all three voltages and should be set to deliver 5V
+/-0.1V, and 12V +/-0.3V on the Interface Logic board at 1A7.
U19 INPUTS
1 CLOCK LOGIC CLOCK
2 VIS_HI_VSWR
3 AUR_HI_VSWR
4 VIS_FB_ACT
5 AUR_FB_ACT
6 INTERLOCK
7 LOSS_OF_VID
8 50V_OK
9 TX_ON
10 DC_OK
11 PRESS_ON
13 DELAY
U19 OUTPUTS
18 AGC_DISABLE Reduces AGC output to a safe drive level when: A) PRESS_ON & 50V_OK are low. B)
50v_ok is low & LOSS_OF_VID & PRESS_ON are high.
19 !RET_RESET Module reset when:
A) PRESS_ON & 50V_OK are low
B) 50V_OK is low & LOSS_OF_VID & PRESS_ON are high
20 !50V_EN Enables 50 volt supplies when
TX_ON is low.
21 !AC_ON Control to apply AC to 50 volt
supplies when TX_ON is low and
INTERLOCK,
LOSS_OF _VID are high.
22 *F/B_ACT Visual and aural are in
foldback condition
23 !HI_VSWR Visual or aural is higher than the VSWR set points
Table 4-5. U19 Input & Output Functions
Section IV - Theory of Operation
Rev. B: 7/15/02 888-2457-001 4-7
WARNING: Disconnect primary power prior to servicing.