Sony XR-4803 Section Mechanical Adjustments, Section Electrical Adjustments, Tape Deck dB=0.775

Page 14

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.

 

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Image 14
Contents Specifications XR-4803Flexible Circuit Board Repairing Table of ContentsDiagrams Section General Page Page Page Page Page Cover ASS’Y Section DisassemblyFront Panel ASS’Y SUB PANEL, Mechanism Deck MG-25F-136 Main BOARD, Heat SinkSection Assembly of Mechanism Deck HousingLever LDG-A / LDG-B Gear LDG-FTGuide C Tape Deck dB=0.775 Section Mechanical AdjustmentsSection Electrical Adjustments FM Auto Scan/Stop Level Adjustment Tuner dB=1 µVSource and Mode button MW AM MW Auto Scan/Stop Level AdjustmentPin No Pin Name Function Section DiagramsIC PIN Function Description REL Uniso Page Page Page IC351 IC Block Diagrams Main Board IC301 CXA2509AQ-T4IC331 LC75373ED IC611 BA3918-V2 1211 Section Exploded ViewsChassis Section 108 107 105 111 121 114 112 104 103 113 101 117 116 106 115 Front Panel Section102 118162 Mechanism Deck Section MG-25F-136159 158 155 154 157 156 153 152 168 151 160 163 161 164 165 168 166 167Section Electrical Parts List KEYKEY Main Double Layer Inductor Tuner TU1 502 501 503504 505 Screw +BXR-4803