Figure 3-5. Write/Read Skew Waveform.

11-5835-243-34/EE641-AA-MMI-010/E154

MTT/TO

31S3-4-110-1

(3) When tape transport reports BOT status,

set WRITE switch to off.

(4) Depress RUN FORWARD switch on

exerciser. Wait 10 seconds and depress STOP

switch. Cycle tape transport ON/OFF switch off,

and after one second, on. Repeat five times.

(5) Depress REWIND switch on exerciser.

Wait for BOT to be reported.

(6) Ensure that WRITE switch is off. Reset

PARITY ERRORS counter and depress RUN

FORWARD switch. Monitor error counter during

first one minute of command READ operation.

Verify that counter indicates zero.

(7) Depress REWIND switch on exerciser.

Wait for BOT to be reported.

b. Error Test.

(1) Set WRITE switch on exerciser on. Set ALL

PAT switch on. Reset PARITY ERRORS counter

and depress RUN FORWARD switch.

(2) Allow tape transport to perform com-

manded read-after-write operation through EOT.

EL4RD048

(3) During above operation, observe error

counter during recording pass (until EOT is

Figure 3-5. Write/Read Skew Waveform.

reported) and verify that there are no errors. If

errors are indicated, repeat entire error test (two

b. Dynamic Skew B.

retries maximum).

(1) Using same settings as above, display

(4) Wait for BOT status to be reported before

signals present at TP4 of digital read/write circuit

continuing.

card A1 on CH1 and TP6 of digital read/write circuit

card A3 on CH2 of the oscilloscope. Set oscilloscope

3-17. Power Consumption Test

to the chopped mode.

a. Low-Speed Read While Write Mode.

(2) Trigger oscilloscope on positive-going edge

(1) Connect digital multimeter (5-amp scale) at

for the signal on Al, TP4 (CH1). Measure time

exerciser TRANSPORT CURRENT jacks.

displacement over which signal jitters. Make note of

(2) When tape transport reports BOT status,

this time.

depress RUN FORWARD switch. Observe that

(3) Tigger oscilloscope on positive-going edge

current does not exceed 2.04 amperes.

of signal on A3, TP6 (CH2). Measure time

b. High Speed.

displacement over which the signal jitters. Make

(1) Depress STOP switch, then depress

note of this time.

REWIND switch on exerciser. Wait for BOT status

(4) Add the times noted in steps (2) and (3) and

to be reported.

verify that dynamic skew B is 6.0 microseconds

maximum

(2) Depress FAST and RUN FORWARD

switches and observe that current does not exceed

(5) Depress REWIND switch on exerciser.

2.04 amperes.

Wait for BOT to be reported.

c. Standby.

3-16. Power Cycling Interference Test

(1) When BOT status is reported, set exerciser

SELECT 1 off and SELECT 2 on.

a. Power Cycling, Write Interface.

(2) Observe that standby current does not

(1) Set WRITE and WRITE DATA ALL 0

exceed 0.65 ampere.

switches on exerciser on. When BOT is reported,

depress exerciser PARITY ERRORS RESET and

3-18. Magnetic Tape Cartridge Test Setup

RUN FORWARD switches.

a. Connect the exerciser to a known good tape

(2) Allow tape transport to perform the

transport as shown in figure 3-1.

operation for one minute. If after that time the error

b. Refer to TM 11-6625-3024-14 for exerciser

counter registers zero errors, depress STOP switch,

operating instructions. Set exerciser controls as

then REWIND switch on exerciser. If errors are

follows:

indicated, repeat procedure (two retries maximum).

3-9