SECTION 4

MECHANICAL ADJUSTMENTS

1. Clean the following parts with a denatured-alcohol-moistened

swab:

 

playback head

pinch roller

rubber belt

capstan

idler

 

2.Demagnetize the playback head with a head demagnetizer.

3.Do not use a magnetized screwdriver for the adjustments.

4.After the adjustments, apply suitable locking compound to the parts adjusted.

5.The adjustments should be performed with the power supply voltage unless otherwise noted.

• Torque Measurement

Mode

Torque Meter

Meter Reading

 

 

 

Forward

CQ-102C

30 – 65 g•cm

(0.42 – 0.90 oz•inch)

 

 

Forward

CQ-102C

0.5 – 4.5 g•cm

Back Tension

(0.01 – 0.06 oz•inch)

 

 

 

 

Reverse

CQ-102RC

30 – 65 g•cm

(0.42 – 0.90 oz•inch)

 

 

Reverse

CQ-102RC

0.5 – 4.5 g•cm

Back Tension

(0.01 – 0.06 oz•inch)

 

FF, REW

CQ-201B

60 – 200 g•cm

(0.83 – 2.78 oz•inch)

 

 

• Tape Tension Measurement

Mode

Tension Meter

Meter Reading

Forward

CQ-403A

more than 90 g

(more than 3.18 oz)

 

 

 

 

 

Reverse

CQ-403R

more than 90 g

(more than 3.18 oz)

 

 

SECTION 5

ELECTRICAL ADJUSTMENTS

TEST MODE

This set have the test mode function. In the test mode, FM Auto Scan/Stop Level and AM (MW) Auto Scan/Stop Level adjustments can be performed easier than it in ordinary procedure.

<Set the Test Mode>

1.Set the “power select” switch (S501) is “A” position.

2.Turn ON the regulated power supply. (All LEDs on the set lights up, and the clock is displayed.)

Note: Press the [OFF] button, if the clock is not displayed.

3.Push the preset [4] button.

4.Push the preset [5] button.

5.Press the preset [1] button for more than two seconds.

6.Then the display indicates all lights, the test mode is set.

<Release the Test mode>

1.Push the [OFF] button.

2.Return the “power select” switch (S501) to initially set posi- tion.

See the adjustment location from on page 16 for the adjustment.

TAPE DECK SECTION 0 dB=0.775 V

Tape Speed Adjustment

Setting:

 

 

speed checker

 

 

or

test tape

 

frequency counter

 

 

WS-48A

 

 

(3 kHz, 0 dB)

4

Ω

 

set

 

– +

 

 

speaker out terminal

Procedure:

1.Put the set into the FWD PB mode.

2.Adjust adjustment resistor for inside capstan motor so that the reading on the speed checker or frequency counter becomes in specification.

Specification: Constant speed

Speed checker

 

Frequency counter

–1.5 to +2.5%

 

2,955 to 3,075 Hz

 

 

 

Adjustment Location: See page 16.

 

– 14 –

Page 14
Image 14
Sony XR-4803 service manual Section Mechanical Adjustments, Section Electrical Adjustments, Tape Deck dB=0.775