IBM 3274 51C Maintenance Information page 258

' ; !1
-
, fo.
Write Data BI7" 110 B17
/ /
+Inner Tracks B08" I/O BOB
+WriteGate
BI4~~
I/O BI4
/ ;
+Select HeLd I
Bll" 1/0Bll
/ /
+Erase Gate B09" 110 B09
/ /
+Swltch Filter BI6" I/O BI6
/ /
+Write/Erase Enabled BOO / / 110 BOO
+File Data B07
;~
I/O B07
"" 110 A02-
Ground
A02-AIB', AlB
/ /
Using
-5Vdc
AOI" I/OAOI
System
/ /
Adapter +5V dc
BOI" 110 BOI
/1'
+Index B04 / / 110 B04
"
+Diskette Sense B05 / / 110 BOS
,"
+AccessO Bl0" 110 Bl0
/1'
+Access 1 BI3" 110 B13
/ /
+24V dC
B03" 110 B03
/ /
+ Head Engage
815" 110815
t
7 /
t
~
(see Note 2)
VFO
~
Figure F-11. Control Lines at Connector A 1
"
....
,
...
..
~..
. .
..,
Center rap Read/Write Head 0
Blue : :
ReadIWrlte Head 0
Black I I
r i
HeadO
ReadIWrite
Era .. Head 0 Yellow
~HeadO
Erase Head 0 Red
I
Cable Shield Head 0
y Erase
Cable Shield Head I
Erase Head I
Red
r-..
~Headl
Era .. Head 1 Yellow
I
Erase
Black I
Blue
I
I
I , . . . "' " .
H.~
,
I
Center Tap ReadIWrite Head
~Headl I
~eadIWrlte Head I
White: •
J
ReadIWrite
......,
---.-
~~" H.m"",~.~,H'"
TPCTO TPCTl
~
TPB06 . -SV dc
Diff
Read
<.l
TPC02
TPC03 A
'---!-L~
+File Data
'i
TPB04 i - - -
f-<~
AR
,~HOI
y'TPB03
Select
~
Preamp
I--
Dill DET
I--
N
Logic
~~~,.."H:-
i'TPAOS
TPA09
Dill
9
TPD02
+SVdC
TPAMPI CE Test Points Read B TPfOI
Data Oegate
i . - - - - -
+Write/Erase Enabled
I
~ ~ TPAOS
_TPLD2
~ 02 LED Voltage
.J,.
TPA07
LED A03" A03 02 LED Voltage
_ TPB02
~
01 LED Voltage
. / /
-
TPLDI
LED A06" A06 01 LED Voltage
'i
TPC03
01
TPB07 PTX AOI /1' "AOI 01 PTX
TPEOI
r - - -
PTX
/ /
~ ~
7+SV TPA09
Index AR
PTX A03 ././ A03 01 PTX Return
Detee- 02
I
LED AOS " .// AOS 01 LED Ground
"~"
""
~
PTXAOS" '''A05D2PTX
Logoc AR
/ /
-DIsable
Stepper '-----
PTX A04 ././ A04 02 PTX Return
Motor
TPr' THAOS
(see Note!)
LED A01" / / AOI 02 LED Ground
MC.Q ~
Ground
",
~
'y'TPA04 SM A06 / / A06 Stepper Motor MC.Q
A DR
",
TPi01
MC-I
fTPA02
l -
SM A06 ./ / A06 Stepper Motor MC·l
Access
A DR
""
Degate
Logic
MC-2
l -
I'
TPA03 SM A04 / / A04 Stepper Motor MC-2
A DR
"
MC-3
I-
-f
TPAOI
SM A03 / / A03 Stepper Motor MC-3
A DR
T1
01
I...--
"
SM AOI " AOI Stepper Motor Common
HeadLoad
~
SO L A03 1'1' ,,, A03 Head Load Solenoid
TPAOB 0- Head
W / /
TP~OS
Load
Circuit
SOL A04 / / A04
t
"
t
'-----
y Inp
head/stepper motor adjustments.
2. The variable frequency oscillator is packaged in the using system logic. The function of the variable
frequency oscillator is to separate and clock pulses.
Black
Black
, .. "
.~~x~ 01
~ED
Yellow
Red
Black
.~
02
Q
PTX
Yellow
Red
Yellow
;1
100
Ste
Mo
Red
-1-..~
/~2
Orange
~
Blue
Black
Black
Head Load
Solenoid
White
02
LED
per