Kenwood TS-570D Rejecting Interference, If Filter, Noise Blanker, Changing if Filter Bandwidth

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REJECTING INTERFERENCE

IF FILTER

The IF filters are designed for selecting the exact range of intermediate frequencies that are sent to the next stage in the receive circuit. Interference adjacent to the desired signal can be reduced by selecting a narrow bandwidth filter and/or shifting the center frequency of the filter.

To more effectively remove interference, use the IF filters with the DSP filters described on pages 37 and38.

CHANGING IF FILTER BANDWIDTH

When adjacent frequency interference is present at both sides of the desired signal, a narrow IF filter bandwidth may be the best way to remove the interference. Changing the filter bandwidth will not effect the current receive frequency.

To use a narrow filter in SSB, CW, or FSK mode, install the appropriate optional filter {page 58}, and select the appropriate setting in Menu No. 46.

When in CW or FSK mode, the wide filter or the narrow filter is automatically selected, depending on the bandwidth of the DSP filter that you select. Refer to “CHANGING RECEIVE BANDWIDTH” {page 37}. The default in SSB or AM mode is wide bandwidth. In FM mode, you cannot change the filter bandwidth.

Note: When you use Menu B, make sure to select the appropriate filter bandwidth via Menu No. 46 in Menu B.

Interfering	Desired	Interfering
signal	signal	signal

1Select SSB or AM mode.

2Press [FILTER].

• The current filter selection appears.

3Turn the MULTI/CH control to select Wide (“FIL-WID”) or Narrow (“FIL-NAR”).

4Press [FILTER] to complete the setting.

IF SHIFT

For SSB, CW, or FSK mode, shifting the center frequency of the filter pass band is an additional method of fighting adjacent frequency interference. Shifting this center frequency does not change the current receive frequency.

To remove interference that is higher in frequency than the desired signal, turn the IF SHIFT control counterclockwise. To remove interference that is lower in frequency than the desired signal, turn the IF SHIFT control clockwise.

Desired Interfering

signal signal

NOISE BLANKER

Noise Blanker was designed to reduce pulse noise such as that generated by automobile ignitions. Noise Blanker does not function in FM mode.

Press [NB] to toggle Noise Blanker ON or OFF.

•“NB” appears when the function is ON.

36

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Contents TS-570S Applicable Model Supplied AccessoriesAccessory Part Number Intelligent Digital Enhanced Communications SystemFeatures Writing Conventions FollowedKEY2 Contents Scan Memory FeaturesSpecifications Appendix COM Connector Protocol Index Operator ConveniencesPower Lines Power SourcePower Cable Protection CleaningInstallation Antenna ConnectionTransmission Line MHz 14 MHz 30 MHz Ground Connection DC Power Supply ConnectionInstallation Lightning ProtectionAccessory Connections Front PanelRear Panel Your First QSO DSP Slope High control Fully clockwise DSP Slope LOW controlYour Getting Acquainted Front PanelGetting Acquainted TF-SET button UP/DOWN buttonsSplit button Clear buttonMicrophone KEY and Paddle jacks Rear PanelGND post EXT SP jackDisplay @8USB @6M.SCR@7LSB #1FSKOperating Basics Switching Power ON/OFFAdjusting Volume Selecting VFO a or VFO BSelecting a Frequency Selecting a ModeAdjusting Squelch Front Panel MeterSelecting Transmit Power TransmittingMicrophone Gain Menu Access Menu SetupWhat is a MENU? Menu A/ Menu BFunction Selections Default Menu ConfigurationMenu Setup GroupSetting Transfer Rate bps Stop Bits SplitCross Reference for Menu Functions Basic Communicating SSB TransmissionAuto ZERO-BEAT CW TransmissionBasic Communicating TX SIDETONE/ RX Pitch FrequencyTX Deviation Selection FM TransmissionAM Transmission Press FilterTF-SET Transmit Frequency SET Specialized CommunicatingSPLIT-FREQUENCY Operation UP/DWNArrl 10-METER Band Plan FM Repeater OperationSpecialized Communicating Mode/ActivityFM Ctcss Operation Specialized Communicating Selecting Subtone FrequencyContinuous or Burst SUBTONES? Rtty Frequencies Digital OperationRtty Frequency Shift Keying Iaru Region A./CanadaPacket Frequencies Slow Scan TV/ Facsimile Satellite OperationSstv Frequencies Communicating Aids ReceivingSelecting Your Frequency AGC Automatic Gain Control RIT Receive Incremental TuningCommunicating Aids RX EqualizerVOX VOICE-OPERATED Transmit Delay TimePress Delay Microphone Input LevelXIT Transmit Incremental Tuning Communicating Aids Speech ProcessorChanging Frequency While Transmitting Monitoring Transmitted SignalsTransmit Inhibit Changing Transmit Bandwidth SSB/AMCW BREAK-IN Using Semi BREAK-IN or Full BREAK-INAuto Weighting Electronic KeyerCommunicating Aids Changing LOCKED-WEIGHT BUG KEY FunctionCW Message Memory Noise Blanker Rejecting InterferenceIf Filter Changing if Filter BandwidthDSP Tools AttenuatorPreamplifier Rejecting InterferenceNoise Reduction Beat CancelSetting NR2 Time Constant CW/ FSK ModesStoring Data in Memory Memory FeaturesConventional Memory Simplex ChannelsMemory Recall Memory FeaturesSplit-Frequency Channels Memory Recall and ScrollMemory-VFO Split Operation Memory ScrollTemporary Frequency Changes To use a memory channel for receivingMemory Features Memory Transfer Memory VFO TransferChannel Channel Transfer Erasing Memory Channels Memory Features Storing Frequency RangesFull Reset Confirming Start/End FrequenciesMemory Channel Lockout Quick MemoryStoring Into Quick Memory Press CLRMemory Features Recalling Quick Memory Temporary Frequency ChangesQuick Memory VFO Transfer Scan Hold ScanProgram Scan Scan Type PurposeALL-CHANNEL Scan Memory ScanScan Group ScanOperator Conveniences Microprocessor ResetSwitching ANT 1/ ANT Frequency Lock FunctionProgram Function Button Beep FunctionDisplay Dimmer Operator ConveniencesSetting UP Using Quick TransferQuick Data Transfer Computer Control Using a TransverterMenu Setting Transfer Rate Stop Bits Communication ParametersPresetting Automatic Antenna TunerAttune again Recording Messages Message PlaybackChecking Messages Changing Volume Sending MessagesChanging Inter-message Interval Voice New Mode AnnouncementMenu StepsPC-1A Optional AccessoriesDRU-3A PG-2ZInstalling Options Removing the Bottom CaseDRU-3A Digital Recording Unit Installing Options VS-3 Voice Synthesizer UnitFilters SO-2 TEMPERATURE-COMPENSATED Crystal Oscillator Tcxo Compatible Transceiver Connecting Peripheral EquipmentComputer Pin No. Pin NameLinear Amplifier Connecting Peripheral EquipmentRtty Equipment Antenna TunerMCP and TNC Pin No FunctionService Note MaintenanceService CleaningAccessing the Internal Fuse Internal AdjustmentsMaintenance Reference Frequency CalibrationFollowed TroubleshootingProblem Probable Cause Corrective Action DSP Slope LOW control orChanging Receive Press LSB/USB, CW/FSK, orPress LSB/USB or FM/AM to Repeater Operation TS-570S TS-570D SSB, CWFSK, FM Specifications SSB, CW, FSKAppendix Hardware DescriptionControl Operation COMError Messages Computer Control CommandsAlphabetical Commands ParametersAlphabetical Command Table OFF/ONParameter Table FormatMenu Selection Table for EX Command UP/DOWNComputer Control Command Tables I o !0DN UP DOWN/UP LK Frequency Lock MG MIC Gain RT RIT RX TX RX, TX VOX Function VFO Sstv