7
-21
DOUBLE-DENSITY
DISK
CONTROLLER
Integrated
Circuits
(Cont'd.)
u
COMPONENT
NUMBER
PART
NUMBER
MAYBE
REPLACED
WITH
IDENTIFICATION
U3
HE
443-912
74LS148
Vee
INPUTS
INPUTS
-..-
OUTPUTS
OUTPUT
AD
U4
U5
HE
444-81
HE
443-745
*
74LS03P
Vee
WE
RE
A'
U6
HE
444-82
*
AD
AI
A'J
Rii"
7
WR
Be
R/wEN
IN
ii"OTN
IN
11
RTSIT
GND
u
*Only available from Heath Co.
