Midland Radio SP-300 service manual Description of Controls

Page 11

MAXON

SP-300 HAND HELD

DESCRIPTION OF CONTROLS

The controls, indicators and antenna connections on the VHF and UHF Scanning Handheld Series radios are all located on the top panel. The accessories socket is located on the radio chassis right hand side. The monitor and PTT buttons are located on the radio chassis left hand side.

 

 

ITEM

DESCRIPTION

 

1. Antenna Connector

1/4" UNEF socket

 

2.

4 Channel Select Switch

Rotary switch, used to select one of four and to engage in scanning function

 

3.

16 Channel Select Switch

Rotary switch, used to select one of sixteen and to engage in scanning function

 

4.

Status Indicator (busy TX/BT)

Tri-colored LED indicator

 

5.

ON/OFF Volume Control

Main power switch and volume control. Fully counter-clockwise is OFF position

 

6.

Battery Lock

Used to lock the battery in place

 

7.

Push-To-Talk Button

Push to talk, release to listen

 

8.

Monitor Button

When pressed, monitors the chosen channel

 

9.

Option

Used for controlling installed external option

 

10.

Speaker

Sound reception

 

11. Microphone

Sound transmission

 

12.

External Speaker

Socket used for external microphone with speaker

 

13.

Belt Clip

Belt Clip

 

14.

Battery

Power Supply

 

15.

Battery Charger Contacts

Contacts used for charging battery

 

16.

VHF Antenna

Antenna

 

17.

UHF Antenna

Antenna

 

 

 

 

 

 

 

 

 

 

 

ANT

CH

VOL

ANT

CH

VOL

 

4

 

7

 

11

 

3

 

 

 

 

 

 

 

4

 

 

 

2

 

 

 

13

 

1

 

1

 

 

 

 

 

16

 

1

2

3

4

5

7

8

9

CON701 Pinouts

CON701 - Pin 1

Pin

Function

 

1

Data

 

2

Clock

 

3

N/C

 

4

+7.5V

 

5

N/C

 

6

N/C

 

7

Gnd

 

8

Mic+

 

9

N/C

 

10

Int_Spkr_Mic_Dsbl

 

11

Spkr+

 

12

N/C

 

13

16

 

12

 

10

maxon

11

14

17

6

15

Page -8-

May 2001

Image 11
Contents Service Manual Table of Contents Board Layout Exploded View Current Consumption SpecificationsTemperature Range GeneralFrequency Bands DimensionsWeight Adjacent Channel PowerPeak Deviation @ 1 kHz Nom. Dev +20dB ReceiverRX Tone Demodulation Characteristics SP-300INTRODUCTION FeaturesBusy Channel Lockout VCO Lock Time Description Description of ControlsDigital Circuits Theory of OperationRF Circuits RF Circuits PLL Synthesizer Speaker Audio Amplifier Squelch mute CircuitKHz Band Pass Filter Noise DetectorTo replace the belt clip Maintenance and RepairRemoving & Replacing the Belt Clip Removing the belt clipTo remove the PTT assembly Removing & Replacing the BatteryTo remove the battery To replace the batteryRemoving & Replacing the Antenna & Control Knobs Removing & Replacing the ACCES- Sory ConnectorTo replace the Back Cover Removing & Replacing the Back CoverTo remove the Back Cover To remove the Main Board Removing & Replacing the Main BoardTo replace the Main Board Removing & Replacing the Speaker Component ReplacementRemoving & Replacing the DAUGH- TER Boards Surface Mounted Integrated Circuit Replacement Surface Mount Component ReplacementCloning Alignment ProcedureProgramming RX VCO S.G. @ 1kHz Audio Test Equipment SetupTP1 Alignment Points DiagramSymptoms Causes Counter Measures Troubleshooting GuideMain Circuit Voltage ChartsReceive State Transmit State REF# Description PART# SP-300 Series UHF & VHF Digital Section Parts List-30- May REF # Description Replacement Modules SP-300 Series VHF RF Section Parts List-32- May -33- May SP-300 Series UHF RF Section Parts List -35- May -36- May -37- May KTA1504SY Component Pinout-39- May Base Diagram PIN Description UHF FRONT-END VHF Power AMPUHF Power AMP VHF FRONT-ENDUHF V.C.O VHF V.C.OFuse ACC-200 BatteryTcxo SP-300 Series VHF RF Schematic UHF RF Schematic -47- May Board Layout Top Main Board Assembly 416121B -49- May