
IBM 3430 Magnetic Tape
Subsystem
- Announced March 15, 1983 and withdrawn December
19, 1989
The 3430 was a dual density, 50 inch-per-second tape
drive. It read or wrote either 1600 bytes-per-inch phase
encoded (PE) or 6250 bytes-per-inch group coded
recording (GCR). The GCR mode provided more efficient
detection and correction of tape read errors while the
PE mode provided compatibility with and conversion of
existing 1600 BPI tape files. GCR also provided a
greater tape density (6250 BPI), which improved
performance up to 312K bytes per second.
Two models were available in the 1980s:
- Model A01, which consisted of the subsystem
control unit and one tape unit housed in the same
frame.
- Model B01, which was a tape unit only.
Three Model B01s could be attached to a Model A01 for
a maximum of four tape units per subsystem.
The 3430 Subsystem was compatible with existing tape
subsystems and could be attached to the following host
processors:
Some of the advantages provided by the 3430:
- Read and wrote data at lower costs than previous
IBM tape subsystems with similar recording
capabilities.
- Large-scale integration circuitry permitted
reliable subsystem operations at low cost, with fewer
and more condensed printed circuit cards.
- Compact size provided users with increased space
savings. Horizontal tape transport deck permitted easy
tape reel mounting and handling.
- Error correction and improved maintenance
functions designed into the system increased
productivity and reliability.
The side panels were offered in the following colors:
pebble gray, garnet rose, classic blue, willow green,
charcoal brown and sunrise yellow.
The 3430 was developed and manufactured at the IBM
General Products Division facility in Tucson,
Arizona.
Technical Summary
Model
A |
Tape
drive/controller |
Model
B |
Second, third
and fourth drives in
string | |
|
GCR |
PE |
Density,
BPI |
6,250 |
1,600 |
Instantaneous data rate, KB/S
|
312 |
80 |
Tape
speed, IPS |
50 |
50 |
Maximum
tape length, feet |
2,400 |
2,400 |
Capacity
MB (block=16KB) |
152 |
43 |
Rewind
time (2,400'), minutes |
2.7 |
2.7 |
Interblock Gap*, inches
|
.45 |
.60 |
Read/Write access time, ms
|
6 |
6 | | * Difference in gap size did not prevent
tape interchange with IBM 3420 tape drives.
|