Akai CS-34 - DOLBY N.R. CIRCUIT ADJUSTMENT

Vil. DOLBY N.R. CIRCUIT ADJUSTMENT
Adjust Dolby N.R. Circuit carefully as following pro-
cedures in Chart 2.
Connecting Method:
FREQUENCY
ATTENUATOR
COUNTER
AUDIO CONNECT WITH CONNECT WITH | HIGH
FREQUENCY
OSCILLATOR
LINE
INPUT
B
POINT
SENSITIVITY
OUTPUT
INPUT OUTPUT |]
NOTES:
1. Since crucial frequency and level etc. is determined
by Dolby N.R. Circuit adjustment, be sure to use
only correctly calibrated measuring instruments.
2. Level deviation must be within +0.5 dBm.
3. Paint lock all semi-fixed resistors following adjust-
ments.
4. Because adjustment error will occur from recording
bias leakage, be sure to disconnect power supply lead
wire from Oscillator circuit prior to Dolby N.R.
Circuit adjustment.
5. Refer to Fig. 12.
7 oe : —
Dolb Adis : Result;
Item Mode ee TP. ee B point Remarks
Switch Part
Level
19 kHz 19 kHz L2 Minimum
Filter Line Input 23 mH Level
[oF en es
5 kHz External
Line Input Bet Ore a Attenuator soem
Reduce
= ea REC OFF GND Input -28.5dBm | p al i
Recording Line Input 30.5 dBm ec. Leve
Dolby ee Ses a eg te ce
Adjustment ‘ :
: ae REC ON GND 1 kB -18.5 dBm maximum
Line Input | CW-5214
5 kHz Disconnect VR-1 -20.5 dBm
instant ON from 5 kB 2 dBm
a GND CW-5214 decrease
5 kHz -28.5 or
Playback dBm recorded OFF — - Line Out
Dolby Test Tape -28.5 dBm he as
Confirma- | 5 Hz -28.5 or
tion dBm recorded = = Line Out
[L Test Tape = -38.5 dBm
Chart 2
Noise reduction circuit made under license from Dolby Laboratories Inc.
12 The word ‘DOLBY’ and the Double-D symbol are trademarks of Dolby Laboratories Inc.