AIWA HSTA493
Service Manual

ADJUSTMENT
A MAIN C.B

PRACTICAL SERVICE FIGURE
<TUNER SECTION>
4
Sensitivity : (IHF, THD 3%) F M Less than 17dB [at 88.0MHz] Less than 17dB [at 98.0MHz] Less than 17dB [at 108.0MHz] (S/N 10dB) A M Less than 57dB [at 600kHz] Less than 56dB [at 1000kHz] Less than 56dB [at 1440kHz] S/N Ratio : F M More than 53dB [at 88.0MHz] More than 53dB [at 98.0MHz] More than 53dB [at 108.0MHz] A M More than 25dB [at 600kHz] More than 27dB [at 1000kHz] More than 27dB [at 1440kHz] Intermediate frequency : F M 10.7MHz ± 0.1MHz A M 455kHz ± 3kHz FM stereo separation : More than 17dB [at 98.0MHz]

VOLUME

VR101

6 7

PHONES J101

L203

PVC1 TC203

7
L202 L205 L204 SFR 101

<TAPE SECTION>
Tape speed : : Wow & flutter Take-up torque : F.F torque : Rew torque : Back tension : S/N ratio : Distortion : Noise level : 3015Hz ± 60Hz Less than 0.5% (RMS) 24 ~ 45g-cm (FWD) 70 ~ 150g-cm 70 ~ 150g-cm 1.5 ~ 4.0g-cm (FWD) More than 40dB Less than 3.0% Less than 5.0mV (Vol MAX, without tape) Less than 0.3mV (Vol MIN, without tape) 63Hz + 0.5/� 7.5dB ~ 8kHz + 4/� (NORM) 63Hz + 2/� 6dB ~ 10kHz + 4/� 5dB (METAL) TTA� 100 TTA� 210 TTA� 310 (METAL) TTA� 320 (NORM)

4 2

TC204

TC202

TC201

3

5

5

1

2 3

67

L201 BAR ANT

1. AM IF Adjustment L205........................................... 450kHz 2. AM Frequency Range Adjustment L204................................ 517kHz±5kHz TC204.......................... 1750kHz±10kHz 3. AM Tracking Adjustment L201........................................... 600kHz TC201...................................... 1400kHz 4. FM Frequency Range Adjustment L203......................... 87MHz±0.1MHz TC203.................... 109MHz±0.1MHz 5. FM Tracking Adjustment L202........................................ 88.0MHz TC202 ................................... 108.0MHz

A R115

<TUNER SECTION>

7. GOVERNER Adjustment Perform the STOP �> PLAY and REVERSE operations (or PAUSE ON �> OFF) after the motor is replaced. When the tape starts running smooth, this adjustment is not necessary. If wow is conspicuous at the beginning of the tape-run, perform this adjustment following the procedures below. 1) Solder resistor pattern (A) of the MOTOR AND GOVERNOR MATCHING ADJ. resistor group. 2) Set the tape speed (using speed adjustment SFR101). 3) Restrict the motor rotation by hand (or turn PAUSE ON). 4) Remove your hand and listen to the beginning of the tape-run. 5) When the rise of tape running is smooth, no more adjustment is necessary. If wow continues for 1 to 2 seconds at the rise time, change the combined resistance according to procedure 6 and check that the tape starts running smooth. 6) Solder the resistor pattern according to the table below
B R116 C R117

Frequency response : 4dB

Test tape :

<TAPE PLAYER SECTION>
6. Tape Speed Adjustment Settings : � Test tape : TTA�100 (Tape center) � Test point : PHONES (J101) � Adjustment location : SFR101 � MSP : CLASSIC � TAPE SELECTOR : NORM � VOLUME : MAX Method : Play back (FWD) the test tape and adjust SFR101 so that the frequency becomes 3010Hz±10Hz. Then confirm WOW is less than 0.50%.

Pattern (Procedure 1 above) Step (1) Step (2) (NOTE :
A

Low resistance (A) Solder Solder Solder =1.2ohm ,

Medium resistance (B) Open Solder Solder
B

High resistance (C) Solder Open Solder
C

=1.5ohm ,

=8.2ohm)

7) Finally re-check the tape speed.

Caution : Cool the patterns down to normal temperature after soldering. If the pattern remains heated, the gorvernor circuit does not operate normally.

9

10