where it is compared with a user set power value to cause the
output power to foldback. Normally the visual is set to start
foldback at 1.2:1 VSWR reflected power and the aural for a 1.6:1
VSWR reflected power.
4.4.3
High VSWR
These circuits compare the visual and aural reflected power
samples to a user set power value. If the sample exceeds the user
value the HIGH VSWR indicator is turned on. This point is
normally set for 1.5:1 VSWR visual and 1.8:1 for aural. Each PA
module also monitors the VSWR and will fault if module re-
flected power exceeds 90 watts.
The hi VSWR circuit has an option jumper which if selected
(JP16, 1 to 2) will turn off the transmitter when the set point is
exceeded. The transmitter will remain off until the transmitter
OFF button is pressed to clear the HI VSWR fault indicator.
If JP16 is in the 2 to 3 position a HI VSWR fault will be indicated
but the transmitter will remain on air until module VSWR fault
occurs.
4.4.4
Command Input Logic PAL U8 (917-2321-004)
The command input logic PAL U8 interfaces the LOCAL and
REMOTE command inputs. When the LOCAL mode is selected
all REMOTE commands are inhibited.
See Table 4-3 for U8 Input and Output Functions
4.4.4.1
XMTR CTRL PAL U15
The XMTR CTRL PAL U15 (917-2321-007) provides the logic
to interface with the rf modules, power supply, video loss timer
and fault indicators.
See Table 4-4 for U15 Input & Output Functions
4.4.4.2
Fault Encoder U19 (917-2321-008)
This PAL is used to combine input signals to produce outputs as
detailed below.
See Table 4-5 for U19 Input & Output Functions
4.4.4.3
50V OK
This circuit monitors the 50 volt supply and the comparator
output will go low when the supply reaches 48 volts. At this point
the modules can be enabled and the transmitter is operational.
INPUTS
PIN NO.
NAME
FUNCTION
1
CLK
Clock register
2
ON
Local transmitter ON command
3
OFF
Local transmitter OFF command
4
LOCAL
Local mode of control
5
SPARE_INPUT
Not used
6
INT_LOC
External interlock
7
AUR_LOWER
Remote aural lower command
8
AUR_RAISE
Remote aural raise command
9
VIS_LOWER
Remote visual lower command
10
VIS_RAISE
Remote visual raise command
11
RMT_OFF
Remote transmitter off command
13
RMT_ON
Remote transmitter on command
OUTPUT LOGIC STATES
14
MOD_FLT_RST
USED to reset modules, pin goes high for: A) Transmitter ON button is pressed,
B)
RMT_ON command is active,
C)
LOSS_RESET is active.
15
!TX_ON
Used to latch XMTR ON condition. pin goes low for: A) TXON is low and TXOFF is high
b)
SEL_REMOTE, EXT_INTERLOCK, TX_OFF, RMT_TX_OFF are high and RMT_TX_ON is low.
16
!TX_OFF
Used to turn transmitter off.
17
INTERLOCK
Used by EXT INT_LOC to inhibit AC mains to the 50 volt supply if interlock is not closed.
Pin 17 is high if EXT INT_LOCK is low.
18
!LOCAL
Used to inhibit all remote inputs if LOCAL switch is pushed to on. Sets pin 18 low if
SEL_REMOTE is low.
19
VIS_RAISE
Enables remote visual raise command
20
!VIS_LOW
Enables remote visual lower command
21
!AUR_RAISE
Enables remote aural raise command
22
!AUR_LOWER
Enables remote aural lower command
Table 4-3. U8 Input & Output Functions
Section IV - Theory of Operation
Rev. B: 7/15/02
888-2457-001
4-5
WARNING: Disconnect primary power prior to servicing.
Содержание Platinum HT EL 2000HS
Страница 4: ...This page left blank intentionally ...
Страница 6: ......
Страница 8: ...ii ...
Страница 12: ...This page left blank intentionally ...
Страница 26: ...Figure 2 3 Platinum Series 2 8 888 2457 001 WARNING Disconnect primary power prior to servicing ...
Страница 27: ...Figure 2 4 Section II Installation 888 2457 001 2 9 WARNING Disconnect primary power prior to servicing ...
Страница 28: ...Figure 2 5 Platinum Series 2 10 888 2457 001 WARNING Disconnect primary power prior to servicing ...
Страница 29: ...Figure 2 6 Section II Installation 888 2457 001 2 11 WARNING Disconnect primary power prior to servicing ...
Страница 30: ...Figure 2 7 Platinum Series 2 12 888 2457 001 WARNING Disconnect primary power prior to servicing ...
Страница 31: ...Figure 2 8 Section II Installation 888 2457 001 2 13 WARNING Disconnect primary power prior to servicing ...
Страница 32: ...Figure 2 9 Platinum Series 2 14 888 2457 001 WARNING Disconnect primary power prior to servicing ...
Страница 33: ...Figure 2 10 Section II Installation 888 2457 001 2 15 WARNING Disconnect primary power prior to servicing ...
Страница 34: ...Figure 2 11 Platinum Series 2 16 888 2457 001 WARNING Disconnect primary power prior to servicing ...
Страница 38: ...This page left blank intentionally ...
Страница 46: ...This page left blank intentionally ...
Страница 54: ...This page left blank intentionally ...
Страница 88: ...This page left blank intentionally ...