Midland Radio SP-300 service manual Receive State

Page 30

MAXON

SP-300 HAND HELD

RECEIVE STATE

PIN #

IC1

IC2

IC3

IC5

IC6

IC401

IC402

1

GND

1.6

-

4.0

1.4

0.0

0.0

2

GND

5.0

-

3.5

GND

1.0

0.0

3

GND

5.0

-

4.0

0.0

1.3

AUDIO

4

5.0

5.0

-

4.1

GND

0.0

0.0

5

GND

5.0

-

3.8

AUDIO

0.0

5.0

6

7.5

0.0

-

3.8

7.5

0.0

0.0

7

 

0.0

-

3.8

4.0

0.0

0.0

8

 

0.0

-

4.2

1.5

2.0

0.0

9

 

5.0

 

AUDIO

 

0.0

4.0

10

 

2.6

 

0.8

 

4.0

0.0

11

 

2.6

 

1.0

 

4.0

0.0

12

 

5.0

 

0.0

 

5.0

0.0

13

 

3.0

 

4.0

 

0.0

0.0

14

 

5.0

 

GNS

 

5.0

5.0

15

 

0.0

 

0.0

 

 

 

16

 

0.0

 

1.8

 

 

 

17

 

5.0

 

 

 

 

 

18

 

0.0

 

 

 

 

 

19

 

0.0

 

 

 

 

 

20

 

2.5

 

 

 

 

 

 

 

 

 

 

 

 

 

PIN #

IC404

IC406

IC407

IC408

IC410

IC411

 

1

-

3.0

1.9

0.0

AUDIO

2.0

 

2

-

1.9

0.0

0.0

AUDIO

AUDIO

 

3

-

1.9

1.9

0.0

AUDIO

4.0

 

4

-

5.0

1.9

0.0

5.0

AUDIO

 

5

-

1.9

1.9

GND

AUDIO

AUDIO

 

6

-

1.9

5.0

5.0

AUDIO

GND

 

7

-

1.9

1.9

5.0

AUDIO

GND

 

8

-

1.9

A

5.0

AUDIO

GND

 

9

-

1.9

CLK

 

AUDIO

0.0

 

10

-

1.9

0.0

 

AUDIO

0.0

 

11

-

GND

5.0

 

5.0

5.0

 

12

-

1.9

0.0

 

AUDIO

0.0

 

13

-

1.9

1.9

 

AUDIO

1.9

 

14

-

1.9

1.9

 

AUDIO

1.9

 

15

 

 

 

 

 

AUDIO

 

16

 

 

 

 

 

5.0

 

17

 

 

 

 

 

 

 

18

 

 

 

 

 

 

 

19

 

 

 

 

 

 

 

20

 

 

 

 

 

 

 

zNOTE: IC4, 403 and 405 are not fitted on this model series.

Page -27- May 2001

Image 30
Contents Service Manual Table of Contents Board Layout Exploded View General SpecificationsTemperature Range Current ConsumptionAdjacent Channel Power DimensionsWeight Frequency BandsReceiver Peak Deviation @ 1 kHz Nom. Dev +20dBRX Tone Demodulation Characteristics Features SP-300INTRODUCTIONBusy Channel Lockout VCO Lock Time Description of Controls DescriptionTheory of Operation Digital CircuitsRF Circuits RF Circuits PLL Synthesizer Noise Detector Squelch mute CircuitKHz Band Pass Filter Speaker Audio AmplifierRemoving the belt clip Maintenance and RepairRemoving & Replacing the Belt Clip To replace the belt clipTo replace the battery Removing & Replacing the BatteryTo remove the battery To remove the PTT assemblyRemoving & Replacing the ACCES- Sory Connector Removing & Replacing the Antenna & Control KnobsRemoving & Replacing the Back Cover To remove the Back CoverTo replace the Back Cover Removing & Replacing the Main Board To remove the Main BoardTo replace the Main Board Component Replacement Removing & Replacing the DAUGH- TER BoardsRemoving & Replacing the Speaker Surface Mount Component Replacement Surface Mounted Integrated Circuit ReplacementAlignment Procedure ProgrammingCloning RX VCO Test Equipment Setup S.G. @ 1kHz AudioAlignment Points Diagram TP1Troubleshooting Guide Symptoms Causes Counter MeasuresVoltage Charts Main CircuitReceive State Transmit State SP-300 Series UHF & VHF Digital Section Parts List REF# Description PART#-30- May SP-300 Series VHF RF Section Parts List REF # Description Replacement Modules-32- May -33- May SP-300 Series UHF RF Section Parts List -35- May -36- May -37- May Component Pinout KTA1504SY-39- May Base Diagram PIN Description VHF FRONT-END VHF Power AMPUHF Power AMP UHF FRONT-ENDVHF V.C.O UHF V.C.OACC-200 Battery TcxoFuse SP-300 Series VHF RF Schematic UHF RF Schematic -47- May Board Layout Top Main Board Assembly 416121B -49- May