Akai M-9 - CROSS TALK; FREQUENCY RESPONSE

CROSS TALK (Cross talk between the tracks)
(TAPE)
Tape direction ——_—___————— Tape direction
Red |”
(3) 9050505850 ees: \_ @
| ®
As shown in the figure, first record a 1,000 cps sine wave on track No. 3 at +3 VU level. Next, remove the 1,000 cps input signal
and record under a non-input condition.
Then, playback the tape on track No. 3 and No. 1 (reversed condition of tape) through the 1,000 cps B.P.F. (Band Pass Filter, Sen-
sitivity .... 1: 1) and obtain a ratio between the two from the following formula.
C = Desired cross talk ratio (db)
Eo Eo= 1,000 cps signal output level
C = 20log ——-— (db) E2= 1,000 cps cross talk output level WLLL,
E2— Ei E1= No-input signal record level BRSSSSoey
FREQUENCY RESPONSE
Audio
Frequency
Oscillator
Input Output
Connect the measuring instrument as in the above diagram, and measure the frequency response in the following sequence:
RECORD:
1) Give a sine wave of 1,000 cps to the Line Input of the recorder to be tested through an attenuator from an audio frequency
generator.
2)
Set
the
Record/Playback
Knob
in
“Rec”
position
and
adjust
the
line
input
volume
so
that
the
VU
meter
needle
indicates
sg”? VU.
3) Under the condition described in (2), lower the input level 10 db by means of the attenuator.
4)
Record
the
spot
frequency
in
the
range
of
30
cps
to
25,000
cps
from
the
audio
frequency
generator.
PLAYBACK:
5) Set the Record/Playback Knob in “Play” position.
6) Set the Equalizer Switch on 7-1/2” or 3-3/4" position.
7) Connect a V.T.V.M. to the Line output.
8) Playback the tape previously recorded.
9) Adjust the output level to “0” dbm at 1,000 cps as indicated on the V.T.V.M. by the range selector of a V.T.V.M.
10) Playback the recorded spot frequencies with the conditions in (9); make amemo of output level and plot the value on a graph.