23
CHANNEL
MUTE
LEDs
CHANNEL
MUTE
SW ITCHES
CHANNEL
ANALO G
SW ITCHES
M ASTER
SECTION
M UTE
LEDs
M ASTER
SECTION
M UTE
SW ITCHES
M ASTER
SECTION
ANALOG
SW ITCHES
MUTE
CO NTROL
SW ITCHES
M UTE
CO NTRO L
LEDs
NUM ERIC
DISPLAY
ADD
LATCH
74HC573
EPROM
6116
SRAM
6116
CPU
80C51
AD0-AD7
A0
-A
1
3
A8-A13
NVRAM
24C65
MUTE CONTROL BOARD
MUTE SW ITCH BOARD
OUTPUT DIGITAL BOARD
LAST CHANNEL BOARD
PREVIOUS CH'S
LED DATA
LOAD LED
P-CLOCK
FET D ATA
LOAD FET
SW ITCH DATA
LOAD SW ITCH
CLOCK
ULTRA M UTE SERI AL D ATA
RS-232
M IDI IN
M IDI OUT
PW R DIST PCB
EPROM
27C128
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74
H
C
59
5
74H
C
165
74H
C
165
74
H
C
16
5
74
H
C
16
5
74
H
C
59
5
74H
C
165
74
H
C
16
5
74
H
C
59
5
74
H
C
16
5
74
H
C
59
5
74H
C
595
UART
6850
SO
L
O
C
L
O
C
K
MU
T
E
B
U
S
`
U LTRAM U TE
SIM PLIFIED SC HEM ATIC
MUTE BUS