Kennedy 331 User manual

KENNEDY CO.
Operation and maintenance manual
lVIodel331
Digital Cartridge
Recorder

106-0331-100
SECTION I
APPLICATION DATA
1.1 INTRODUCTION
The Kennedy Model 331 Cartridge Recorder is a
rugged tape handler expressly designed for high re-
liability digital data recording. .
The machine utilizes the 3M DC300A converter 1/4
inch data cartridge, which features a unique isoelastic
drive system for maintaining constant tape tension
and tape motion with a single drive motor. Drive
power is provided by a high quality AC motor/tach-
ometer velocity servo system which provides both
tape and reel drive. The cartridge contains 300 feet
of 0.25 inch computer grade tape, along with internal
tape guides to ensure reliable recording.
The Mode1331 is fully bidirectional at 25 ips normal
speed, resulting in a data transfer rate of 40,000
bits per second at 1600 cpi recording density. For-
ward and reverse search modes as well as rewind
speed are 90 ips.
The drive can be equipped with a variety of heads
for maximum flexibility. One, two and four-track
versions are available. Each track is treated in-
dependently, allowing cartridge interchange between
transports of differing track configurations. Every
track is equipped with a separate erase gap to ensure
against inadvertent data erasure.
The Model 331 is designed to meet the requirements
of the proposed ANSI standard for quarter-inch car-
tridges. The standard provides for a recording
density of 1600 cpi written in aphase encoded format.
A 16 character preamble precedes the data for read
synchronization. Data is followed immediately by a
16
character CRC and then a 16 character postamble.
Record gaps are 1. 2 inches minimum.
The write electronics in the Model 331 consists only
of head drivers. The proper phase encoded data in-
cluding preamble, CRC and postamble must be pre-
sented to the unit in the correct serial order. .
Read electronics consist of preamplifiers and cross-
over detectors. Outputs are in digital form, TTL
compatible.
The Model331 provides an extremely reliable means
of storing digital data. It is well suited to use as a
programming device for minicomputers, a storage
1·-1
•
device for terminal and pOint-of-sale systems, and
any other data processing applications requiring
maximum capability in minimum space.
1.2 ELECTRICAL/MECHANICAL SPECIFICATIONS
Table 1-1 lists the general specifications for the
Model 331. Figure 1-1 is an outline and installation
drawing for this unit.
Cartridge type 3M, DC300A Isoelastic
Data Cartridge
Tape width •• • 0.25 inch, 1. 0 mil
Tape length • • • • • • • • • • • 300 feet
Recording density. • • • • • • • • 1600 bpi
Number of tracks. • •••• 1, 2, or 4
Recording head. • Dual gap read-after-write
wi th separate erase bar for each track
Record format • • Single track, phase encoded
Record mode • • • • • • • Single track serial
Normal tape speed •••••••••••••• 25 ips
Rewind/search tape speed • • • •• 90 ips nominal
Start/stop time •••••• at 25 ips, 30 ms ±1 ms;
at 90 ips, 120 ms nominal
Start/ stop displacement ••• at 25 ips, 0.375 inch;
at 90 ips, 5. 4 inches nominal
Transfer rate •••••••• 40,000 bits per second
Instantaneous speed variation • • ±5 percent
Long term speed variation • • • ±!2 percent
Write Bidirectional
Read ••••••••••
Power requirements
Weight. •••
Bidirectional
• •+5 vdc at 0.5 amp
±24 vdc at 3 amps peak
(unregulated)
• 3.75 pounds
Dimensions • • • • • • • • • • • • 6.5 inches wide,
4.75 inches high, 8.625 inches deep
(16.51 em x 12.06 em x 21. 9 em)
Interface •••••••••••• DTL/TTL low true
Table 1-1. Specifications

1.3 INTERFACE CONNECTORS
The interface connectors on the Kennedy Model 331
cartridge transport are designed for twisted pair in-
puts and outputs. The mating interface connector
consi'3ts of one 44 pin Cinch Jones. Refer to Figure
1-4 for interface assignments.
1.4 INTERFACE SIGNAL CHARACTERISTICS
The tape unit responds to zero-volt true inputs' and
provides zero-volt true outputs. Logic 1 = Ov to
+0.4 vdc, while logic 0 = +2.8 vdc to +5 vdc. Each
signal 'input is terminated in such a manner as to
provide matching for twisted pair cables (see Figure
1-2). Each output line is driven with anopen collector
dri ver. For best results the typical interfacing
circuit configurations shown on Figure 1-2 should be
used. The recommended twisted pair cable will re-
duce the magnitude of intercable crosstalk. Unless
otherwise specified, all wires should be 24 AWG
minimum, with a minimum insulation thickness of
0.01 inch. Each pair should have not less than one
twist per inch, and cable length between transport
and control unit should be no more than 20 feet.
The input receiver circuits, due to zero true current
sinking logic design, will interpret a disconnected
wire or removal of power at the format control unit
as a logic zero or false condition. The logic 1 or
true state requires 25 rnA current sink with less than
0.4 volt •. The logic 0 or false state will be +3 volts
due to the input matching resistors. Each output line
is driven with anopen collector current· sinking logic
driver which is capableof sinking up to 40 milliamp-
eres in the true state. All outputs are disabled' when
the tape unit is not on line and selected.
1.5 TAPE MOTION COMMANDS
The Model 331 responds to four input tape motion
. commands: RUN FORWARD, RUN REVERSE, FAST
FORWARD
and FAST REVERSE. The transport in-
cludes a linear ramp generator which drives the cap-
stan servo and provides linear accelerations from
full stop to required speed, and linear deceleration
from run to stop. Start and stop operations occur
within the interrecord gaps. The ramp time is 30
milliseconds for the standard synch~onous speed
(25 ips). Ramp time for 25 ips is adjusted so that
the amount of tape travel during the ramp-up or
ramp-down is always 0.375 inch.
The ramp time and tape travel during the ramp must
be taken into consideration when writing andgapping.
A delay is required before. writing to insure that the
1-2
106-0331-200
tape is up to speed, and to allow read after write. An
additional delay is required before terminating RUN
FORWARD during a write mode to allow for the spac-
ing between the read and write heads. The timing
diagram, Figure 1-3, provides the necessary infor-
mation to produce properly formatted tapes.
1.6 CONTROL SIGNALS
Pin U - RUN FORWARD COMMAND (RF). A level
that when true and the transport is ready causes tape
to move forward at the normal speed. When the level
goes false, tape motion ramps down and ceases.
Pin T - RUN REVERSE C9MMA~D (RR). A level
that when true and the transport is ready causes tape
to move in the reverse direction at the normal speed.
Pin S - FAST REVERSE COMMAND (FR). A level
that when true and the transport is ready causes tape
to move in the reverse direction at the search speed.
When the level goes false, tape motion ceases.
Pin R - FAST FORWARD COMMAND (FF). A level
that when true and the transport is ready causes tape
to move in the forward direction at the search speed.
When the level goes false, tape motion ceases.
Pin J - CARTRIDGE RELEASE (CR). Apulse which
will cause the cartridge to be ejected. The cartridge
release solenoid is actuated on command from the
interface, releasing the 3M cartridge whenever CAR-
TRIDGE RELEASE
goes true. To protect the car-
tridge release solenoid, the input command is inter-
nallytimed out in the event that CARTRIDGE RELEASE
is not turned off after the cartridge has been ej ected •
Pin N - WRITE ENABLE (WEN). A level that when
true and when a cartridge with the write plug in the
write position has been mounted on the transport
allows writing of data •
1.7 STATUS OUTPUTS
Pin P - READY (RDy). A level that is true when the
tape transport mechanical interlocks are made. When
true, the transport is ready to receive a remote
command.
Pin H -PHOTOCELL B. Output levels which provide
position information for determining load point, EOT,
BOT, end of tape warning, etc.
NOTE: It is required that the photocell
outputs be decodecl and stored in order
to accurately deterinine poSition on tape.

410-4012
CARTRIDGE (IN PHANTOfl)
1........ --------- (l~:~~) ----------I ... ~I
'~HOWN IN OPERATING P~OSITION __
.28 MI N.
(.71).
~, __ ~\==:===========================~==~==;T~
1~(1;1' "AX 1 )!
.75
1. 91)
+
------+i ---4+
2.00
5.08 )
.91
2.31 )
MI N.
~
.203 DIA. THRU
(.52) 4-HOLES
.59
) (1.50)
,
)
)
I
4.53
(11.51)
MIN
j I
I
I~
o
o
o
5.75
I.. ~""--------( 14. 61]
~ ___ l-....,...-=-O __ ----0111111~~;;;..;;
2.00
(5.08 )
3.22 I
(8. J8)~
j
.91
(2.31 )
SUGGESTED PANEL )
MOUNTING DIMENSIONS
-+
HOLES TAPPED
FOR 8-32 SCR£WS~
FIRST DIMENSIONS SHOWN ARE IN INCHES.
DIMENSIONS
IN PARENTHESES ARE IN CENTIMETERS.
4.50
(11.43)
3.75
(9.53 )
1
5.75 - 1--- .38
_ 1......... -------------(14.61) - --(.97)
._ 6.50 ------------Jl.~
(16.51 )
I~
o
5.00
( 12.70)
~CARTRIDGE EJECTOR
ACCESS HOLES (LOCATED ON
BOTH SIDES)
". ~2
( 15.54 )
lOG-0331-800A
8.625 _______________ .... 1
(21.91)
Figure 1-1.
Outline and Installation Drawing

----{>o----< I
TTL 7438 I
OR EOUIVALENT I
TAPE TRANSPORT
~I
I
I~
+5V
20 FT MAX
I
I
+5V
TAPE CONTROL
UN IT
106-0331-500
: >---o<J---
110-0074
SFC
STOP
25IPS
RAMP
WRITE
DATA
INPUT
GAP
DETECT
I
11
.375 IN.
0.1 USEC
l
!;:TYPICAL
FALSE
I~
I -:
TYPICAL WAVEFORM OBSERVED
AT LINE TERMINATION
END OF TRANSMISSION LINE
TYPICAL TRANSMISSION DELAY
Figure 1-2. Typical Interface Circuit ,
U
I
I
30
MS
I
WRITE
~
START
DELAY
WRITE
STOP
~~
TYP
DELAY MIN
-4-.10 IN.
.3 IN. ~
. 35 TY P
.375
.375
~1~2
IN. TOTAL GAP-.
I PREAMBLE
OF FIFTEEN
I DAT A RE
COR DIp )STA r~ [3 LE I
OFASINGLE
10'StONEl
ll, FI FTEEN I
D'S
I . I
I I
I I I I
I
30 NSEC
WRITE
START
DELAY
4-.10
IN.
-'-'1
1..-- APPROX
110-0015
12 CHARACTERS
Figure 1-3. Write Motion Command Timing
1- 5

SIGNAL LEVELS
LOGIC 0: +2.8 TO +5 VDC
LOGIC 1: 0 TO +0.4 VDC
PIN
INPUT
SIGNALS
M
WRITE DATA
K
SELECT A
L
SELECT B
N
WRITE ENABLE
J
CARTRIDGE RELEASE
U
RUN FORWARD
T
RUN REVERSE
R
FAST FORWARD
S FAST REVERSE
BINARY
SELECT
PIN
TRK A B V
-1-
0 0 F
2 0 1 H
3 1 0 P
4 1 1 W
PIN
E
C
D
A
B
Figure 1-4. Interface Pin Assignments
1-6
106-0331-600
110-0082
OUTPUT SIGNALS
READ DATA
PHOTOCELL
A
PHOTOCELL
B
READY
SAFE
POWER
CONNECTIONS
+5.0 VDC (0.5 AMP)
+24 VDC (3 AMP PEAK)
-24 VDC (3 AMP PEAK)
SIGNAL GROUND-
MOTOR GROUND

For example, when the cartridge is ini-
tially inserted a rewind operation should
be performed. A fast reverse command
is issued until both the A and B holes
are detected simultaneously in reverse.
When they are, beginning of tape has been
reached and fast reverse should be
dropped. If it is desired to advance to
load point, run forward should be issued
until the A hole is detected in the for-
ward direction. This position on tape ts
LOAD POINT. The next time the A out-
put is detected in the forward direction,
the end of tape warning position has been
reached. Continued forward tape mo-
tion should only be allowed until both the
A and B outputs are simultaneously
detected signifying end of tape.
1.8 READ/WRITE SECTION
Pin V - READ DATA (RD). Data is presented in serial
format, TTL compatible, and consists of coded flux
transitions. A 0 transition is defined as a voltage
transition from low to high at the interface. A 1
transition is defined as a voltage transition from
high to low at the interface. READ DATA OUTPUT
is forced high (false) during the read gap. The par-
ticular track to be read is selected by means of a low
true SD1, 2, 3, or 4 input, which is determined by the
states of SELECT A and SELECT B interface Sig-
nals. Read Data output is forced high (false) during
the Read Gap.
Pin M - WRITE DATA (WD). Serial input data in the
proper phase encoded format, including preamble,
CRC, and postamble, are presented on this line.
Write data consists of encoded flux transitions. The
polarity of this signal is such that a high (false) input
state generates the ANSI standard erase polarity for
gap generation.
Transport electronics consist only of write head
drivers on the Write Head Driver board. WRITE
ENABLE must be true (high) before write data can be
applied to the selected write head. Write head selec-
tion is accomplished by means of SELECT A and
SELECT B interface signals.
1-7
106-0331-700A
Pin K - SELECT A. When combined with SELECT
B, this level selects one of four tracks for read/write
operation. A table of the logic states required to
select each track is furnished on the Transport Elec-
tronics schematic.
Pin L - SELECT B. When combined with SELECT
A, this level selects one of four tracks for .read/write
operation. A table of the logic states required to se-
lect each track is furnished on the Transport Elec-
tronics schematic.
Pin N - WRITE ENABLE. When true (low) this level
enables the write head selected by SELECT A and
SELECT B signal states. When false (high) this level
disables the write heads.
1.9 POWER SUPPLY
The Model 331 requires ±24 vdc unregulated and +5
vdc regulated supply voltage for operation. The
30 ips version of the Model 331 requires ±27 vdc
nominal +20%-10% , in place of the +24 vdc.
The +24 vdc unregulated is reduced to ±15 vdc regu-
lated by a regulator circuit on the Transport Elec-
tronics board. Table 1-2 lists the current and voltage
requirements of the Model 331.
Voltage
+5v ±3%
+24v
+20% -10%
-24v +20% -10%
Current
Maximum O. 95A
Maximum 3. OA
(100 msec surge whe n
ramping - average 1. OA)
Maximum 3.0A
(60 msec surge when
ramping - average 1.0A)
Table 1-2. Power Supply Requirements

206-0331-100
SECTION II
INSTALLATION AND OPERATION
2.1 INSTALLATION
2.1.1 MOUNTING
Physical dimensions and outline of the transport· are
shown in Figure 1-1. The transport requires 4.56
inches of mounting space on a 7.5 inch rack. The
transport should be located so that the cabling length
between the transport and the format control unit is
no longer than 20 feet.
2.1.2 SERVICE ACCESS
The two circuit boards are readily accessible without
dismantling the chassis. To gain access to the mech-
anical parts inside the chassis, detach the connectors
and Write Head Driver board from the Transport
Electronics board. Then detach the Transport Elec-
tronics board from the bottom of the chassis (four
nuts). The front and sides of the Model 331 are
easily removable as one unit for making certain
mechanical repairs.
2.1. 3 INTERCABLING AND POWER CONNECTIONS
The connector pin· aSSignments and cable require-
ments are specified in Section I of this manual. An
external power supply is required for the tape trans-
port. It may be purchased directly from the Kennedy
Company or may be acquired elsewhere. The power
supply connections and specifications are detailed in
Section I.
2.2 OPERATION
Before operating the unit, make certain that all power
supply and formatter connections have been made.
2-1
2.2.1 OPERATING PROCEDURE
After the interface connections are made as required
and the power supply is connected to the transport,
proceed as follows:
a. Clean the transport read/write head to pre-
vent degradation of magnetic tape.
b. USing a screwdriver, rotate the write enable
plug on the cartridge to the SAFE indication
for the read mode, or away from the SAFE
indication for the write mode. When in the
write mode, the WRITE indicator on the
front panel will be illuminated.
c. To insert cartridge, place bottom plane of
the cartridge on the lower ridge of the car-
tridge guides as shown in Figure 2-1. Slide
cartridge all the way in and press until car-
tridge is engaged as shown in Figure 2-1.
d. To eject a cartridge, issue a CARTRIDGE
RELEASE command, which is automatically
disabled after a predetermined delay. The
tape can also be manually ejected by de-
pressing the cartridge ejection mechanism
within the machine with a small Allen
wrench. Two access holes are provided on
the side panels for this purpose. Alterna-
tely, insert the plastic ejector (Kennedy
Part No. 191-4565-001) provided between the
cartridge and the deck to trip the cassette
latches.