Receiver, Front End | Maxon Telecom SP210, SP200 instruction

Maxon SP200/210 Radio

SP200/210

5.7 Receiver

The receiver comprises:

Rx

VCO

~

Audio

Amplifier

Audio

Filter

Local

Oscillator

~

FM Limiter- Discriminator

Squelch

Circuit

Figure 5-4 - Receiver Block Diagram

Antenna Switch

In receive, the diodes D5 and D6 are reverse biased. L13 is now in circuit, passing the signal from the antenna to the front end without signal loss.

Front End

The receive signal is routed to the RF Front End module, pin 1. It passes through a matching circuit consisting of C601 to C603 / L601 & L602.

Diode D601 serves as protection from RF overload from nearby transmitters.

The input signal is coupled to the base of Q601 which serves as an RF amplifier. The output of Q601 is then coupled to a bandpass filter consisting of C604 to C620 / L603 to L607.

The output of the front end module, pin 6, is then coupled to the double-balanced mixer D9.

The receiver front end module is factory pre-tuned and requires no adjustment. Repair is effected by replacement of the entire module.

The modules are:

VHF	146 MHz to 174 MHz
UHF	440 MHz to 470 MHz.

DETAILED FUNCTIONAL DESCRIPTION	Issue 1.0
Page 5-8	03/01

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Maxon Telecom SP210, SP200 service manual Receiver, Front End

Contents

SP200/210 NSW Australia Tel +61 0 2 9707 Issue No Effective Date Reason for Change Signature Amendment Record SheetAmendment Record Sheet Maxon SP200/210 Radio Table of Contents SL100 UHF Parts List 11.4 Default Settings 11-810-1 11-1 List of Tables Maxon SP200/210 Radio Issue 03/01 Using this Manual IntroductionAmendments to this Manual Category C Engineering Bulletin Contact Information Specifications General Environmental Operating Temperature Range Physical Dimensions SynthesiserVibration ESD EMC Accessories & Options Pre-Install Check AccessoriesOptions Accessories & Options INSTALLATION, Commissioning & Alignment InstallationINSTALLATION, Commissioning & Alignment Connections Commissioning Recommended Test Equipment Commissioning Equipment Commissioning Kit Test Equipment Set-up using Discrete Test Equipment Discrete Test Equipment SK 3100 Service Kit Test Equipment Connection Transmitter Performance TestsReceiver Performance Tests Power Adjustment SquelchAudio Output Tests without Disassembly AlignmentPreparation VHF Disassembly and Re-assembly of the Radio Removing and Replacing BatteryRemoving and Replacing the Belt Clip Removing and Replacing the Main Assembly Location of Adjustment PointsPLL Alignment Squelch Sensitivity Transmitter AlignmentTcxo Radiocommunications Test SET Balance Adjustment Audio deviation adjustmentCtcss / DCS deviation Audio Volume Level At maximum volume, nominal distortion is 10%Receiver Alignment Detailed Functional Description IntroductionCommon Circuits Eeprom Audio Signal Path Audio Asic Sat Signal Path Miscellaneous Signals and Controller Audio/SAT Circuits Battery Low Indicator Circuit LEDs and indicatorsCommon RF Circuits PLL Synthesiser PLL IC Out-of-Lock DetectorCharge Pump and Loop Filter DC to DC Converter Antenna Switch Automatic power control APC circuitsTransmitter PA module Receiver Front End First Mixer Second mixer, Second IF, FM detectorSquelch Mute Circuit 16kHz Band Pass Filter Noise detector circuit AF Output Low Pass FilterSpeaker Audio Amplifier Troubleshooting Diagnostic FunctionDiagnostics Troubleshooting Troubleshooting Chart If IC Voltage Charts Transistors Main CircuitMain Circuit Transistor Voltages Integrated Circuits Integrated Circuit Voltages ReceiveIntegrated Circuit Voltages Transmit Troubleshooting Troubleshooting Troubleshooting Troubleshooting Programming SMP6100Introduction Getting Started Select Features Menu ScanningProgram/Print/Save Program Radio Print Data Save Data to Disk Maxon SP200/200 Radio SP200/210 Exploded Mechanical Drawings & Parts Lists Parts ListExploded Mechanical Drawings & Parts Lists Spare Parts SL100U2 SL100V2 Mechanical Parts For details on servicing, please refer to Section Parts List for Exploded Mechanical Drawing LCD TTR 1866 Dpfdpw PCB LCD SKPT-110VASML-020MLTT86 SMD NUT M7 Bsbm PCB VCO PCB RF Aldc Bsbm M2.6 SL100 VHF Parts List V2 Control Circuit05B-000-5Z Diode Switching KDS181S A3 Chip Ceramic 0.001UF GRM39 X7R102K 50V PChip Ceramic 0.012UF GRM39 X7R123K 25V P Chip Ceramic 0.0022UF GRM39 X7R222J 50V P 2 V2 RF SW Tact SKPT-1101VA RES.CHIP Trimmer 1K RH03E1C13X RES.CHIP Trimmer 10K RH03E1C14XThermistor Chip 33KNTCCS32163SH333KC TH1 Elect Capacitor 10UF 16V 20% RE Power Module GNOK-M68776-E01 IC9 Chip Ceramic 39PF GRM40 COG390J 50V PChip Ceramic 43PF GRM40 COG430J 50V P Chip Ceramic 47PF GRM39 COG470J 50V P Tcxo Assembly 4 V2 VCO 5 V2 Front End SL100 UHF Parts List U2 Control Circuit Connector Waffer 2 U2 RF Chip Resistor 12KChip Resistor 18K Chip Resistor 39K RES.CHIP Trimmer K RH03E1C13X Chip Ceramic 0.0015UF GRM39 X7R152K 50V PChip Ceramic 10PF GRM40 COG100C 50V P Chip Ceramic Power Mpduleuhf M68732HGNOK IC9 Chip Ceramic 2.2PF GRM40 COG2R2C 50V PChip Ceramic 470PF GRM40 COG471J 50V P Chip Ceramic 4.7PF GRM40 COG4R7C 50V P Tcxo Coil Chip 18NHLL2012-F18NMCoil Spring X0.35X7TR Coil Spring 2X0.75X3TL SMD 4 VCO Maxon SP200/210 Radio Circuit Diagrams & PCB Layouts Circuit Diagrams & PCB LayoutsRF PCB Tcxo Circuit Diagrams & PCB Layouts Digital Board Layout Top Side Digital Board Layout Bottom Side RF Board Layout Top Side Issue RF Board Layout Bottom Side P406787a Front End Front-End Board Layout Tcxo Board Layout Spare Parts & Maintenance Policy 10SPARE Parts10.1Spare Parts Component Replacement Surface mount component replacementSurface mount components Surface mount removal Surface mounted integrated circuit replacement Spare Parts & Maintenance Policy 11APPENDIX ACC-2003 Alignment BOX 11.1Purpose11.2Test Equipment 11.3Calibration Program Calibration Program Primary Screen Appendix a ACC-2003 Alignment BOX Asic Control Screen Rx Adjustment of Asic values TXTRIM2TXTRIM3 RX VOL Transmit Adjustments SAT BalanceSAT Deviation Receive Adjustments Audio Output Level 11.4Default Settings 11.4.1 V1 Band Default SettingsV1 Default Frequency Table V1 Default Asic Settings 11.4.2 V2 Band Default Settings V2 Default Frequency TableV2 Default Asic Settings 11.4.3 U1 Band Default Settings U1 Default Frequency TableU1 Default Asic Settings 11.4.4 U2 Band Default Settings U2 Default Frequency TableU2 Default Asic Settings