4.6
C
ARD
P
IN
S
IGNALS
..................................................................................................................... 19
4.6.1
Inputs .................................................................................................................................... 19
4.6.2
Outputs.................................................................................................................................. 20
4.7
VCF
C
ARD
T
ROUBLESHOOTING
T
IPS
......................................................................................... 20
4.7.1
Step 00-02: Resonance (Q) Tests ......................................................................................... 20
4.7.2
Step 03: DC Feedthrough Check ......................................................................................... 20
4.7.3
Step 04-11: Initial F
c
and V/Oct Calibration ....................................................................... 20
4.7.4
Step 11-27: VCO Volume Test ............................................................................................. 21
4.7.5
Step 28-31: F
c
& Q Modulation ........................................................................................... 21
4.7.6
Step 32-35: VCO1 & 2 Modulation...................................................................................... 21
4.7.7
Step 36-39: Noise Audio Path .............................................................................................. 21
4.7.8
Step 40-43: VCO Bypass VCF ............................................................................................. 21
4.7.9
Step 43: TL068 Drift Test..................................................................................................... 21
5
DIGIMOD CARD ............................................................................................................................. 23
5.1
T
HEORY OF
O
PERATION
.............................................................................................................. 23
5.2
D
EMULTIPLEXING
E
NABLE
S
IGNALS
.......................................................................................... 23
5.3
M
ODULATION
S
YSTEM
S
CAN
C
LOCKS
........................................................................................ 24
5.4
D
EMULTIPLEXING
/
R
EMULTIPLEXING
........................................................................................ 24
5.5
M
ONO
C
ONTROLLER
M
ULTIPLEXER
........................................................................................... 25
5.6
M
ISCELLANEOUS
S
WITCHING
F
UNCTIONS
.................................................................................. 25
6
KEYBOARD...................................................................................................................................... 26
6.1
T
HEORY
O
F
O
PERATION
............................................................................................................. 26
6.2
C
IRCUIT
O
PERATION
................................................................................................................... 26
6.2.1
Power Retrieval .................................................................................................................... 26
6.2.2
Clock/Strobe Retrieval .......................................................................................................... 26
6.2.3
Digital Data Acquisition ....................................................................................................... 27
6.2.4
Analog Data Acquisition ....................................................................................................... 28
6.2.5
Keyboard Pressure Sensor.................................................................................................... 28
6.2.6
Joystick.................................................................................................................................. 29
6.3
C
ALIBRATIONS
........................................................................................................................... 29
6.4
K
EYBOARD
T
ROUBLESHOOTING
T
IPS
......................................................................................... 29
7
POT PANEL ...................................................................................................................................... 30
7.1
T
HEORY OF
O
PERATION
.............................................................................................................. 30
7.2
K
EYBOARD
C
LOCK
/P
OWER
I
NTERFACE
...................................................................................... 30
7.3
K
EYBOARD
D
ATA
I
NTERFACE
.................................................................................................... 31
7.3.1
Digital Data Retrieval........................................................................................................... 31
7.3.2
Analog Data Retrieval .......................................................................................................... 32
7.3.3
Controllers ............................................................................................................................ 32
7.4
P
ARAMETER
T
RIMMER
M
ULTIPLEXER
........................................................................................ 32
7.5
M
ASTER
V
OLUME AND
M
ASTER
T
UNE
C
ONTROLS
..................................................................... 32
7.6
C
ALIBRATIONS
........................................................................................................................... 33
