T M 32-5835-005-14 & P
h. Set both AGC/MAN switches to MAN.
h. Read ouput of each channel during
each frequency recorded. Observe read-
ing at each frequency is within 3dB of
i. Put unit in REPRO.
1 KHz level.
j. Set output of each channel to 0dB
i. Repeat procedure with speed at 1
with MAN GAIN control.
7/8.
k. Deleted.
8-40. 0utput of Reproduce Amplifiers
and Distortion Test.
a. Set speed 15/16.
l. When section recorded in step f
is passing the head (observe counter
b. Set oscillator to 1KHz at 0dB.
reading), observe that the output is
within 3dB of 0dB on each channel.
c. Put unit in RECORD, set gain
each channel for an output of +7dBm.
m. Deleted.
Reset counter to 000.
d. Record 10 to 20 counts.
8-42. Signal to Noise Ratio.
e. Rewind to 000.
a. Set Speed 15/16.
f. Put unit in REPRO. Set gain pots
full CW. Observe each channel output
b. Set oscillator to 0dB at 400 Hz.
greater than +13dBm on VTVM.
c. Put unit in RECORD. Set MAN
g. Reduce gain controls for an output
GAIN pots each channel for an output
on each channel of +13dBm.
of +7dBm.
h. Measure distortion on each channel.
d. Increase oscillator to +10dB.
Reset counter to 0.
i. Distortion reading should not ex-
ceed 3%.
e. Record 5 to 10 counts.
j. Repeat procedure at 1 7/8 ips.
f. Disconnect oscillator, but con-
tinue recording 5 to 10 more counts.
8-41. Input Level and AGC Test.
g. Rewind to 000. Put machine into
a. Set speed 15/16, both AGC/MAN
REPRO.
switches to AGC.
h. Set gain each channel to +10dB.
b. Set oscillator to 400 Hz, at 0dB.
i. When section recorded in step f
c. Put unit in RECORD, reset counter
is reached, subtract this VTVM reading
to 000.
from level step h. This difference
should be at least 35dB. Do this for
d. Record 5 to 10 counts.
each channel.
e. Increase oscillator drive to
j. Repeat procedure at 1 7/8 ips.
+16dBm.
8-43. Erase Efficiency.
f. Record 5 to 10 counts.
a. Set speed 15/16.
g. REWIND to 000 on counter.
8-25
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