Kenwood TS-870S Instruction Manual

Also see for TS-870S: Instruction manual Operation manual Instruction manual Instruction manual In-depth manual

Contents

49AGC AUTOLSBAUTOMATIC ANTENNA TUNERYou have the choice of using the internal tuner, anexternal AT-300 tuner, or both.Note:◆The antenna tuners will not tune outside the authorized transmitlimits of Amateur bands.◆If an external AT-300 tuner is connected, the internal tuner isbypassed when the ANT 1 connector is selected. The AT-300cannot be used with the ANT 2 connector.◆When tuning in CW mode, the SWR meter may deflect upscalemomentarily. This is not a fault.◆If using Full Break-in CW, the internal antenna tuner can bebypassed completely or can be in-line for both transmitting andreceiving. Even when OFF is selected via Menu No. 08 (RX AT),received signals pass through the antenna tuner. To protect theantenna tuner relay, the tuner cannot be used only fortransmitting.PRESETTING (INTERNAL TUNER ONLY)After each successful tuning session, the Presetfunction stores the data for the position of the tuningcapacitors on each band. Then, if the frequency ischanged while the internal tuner is switched ON, thisfunction automatically positions the capacitors withoutneed for retuning. After changing bands, the Presetfunction activates for the newly selected band.A different set of data is stored for each of the18 antenna tuner bands (see table) and for eachantenna connector (ANT 1 and ANT 2). Therefore,enabling the other antenna connector by pressing the[ANT] button may also cause the Preset function toactivate. If no Preset data exists for a particular band/antenna combination, then the default data for 50 Ω isstored.Presetting does not activate while transmitting. Forsplit-band operation, even if Menu No. 08 (RX AT) isON, the antenna tuner is bypassed while receiving.Also, at all times, presetting is only done for transmitfrequencies.PRESET BANDS FOR INTERNAL TUNERNote:The lower limit is inside the band in each case; the higherlimit is inside the next higher band. For example, 14.1 MHz is inBand 12 whereas 14.49 MHz is in Band 13 (exception: 30 MHz is inBand 18).7 OPERATING AIDSINTERNAL TUNERNote:Setting Menu No. 33 (TUN.WIDE) to OFF to select anSWR≤1.2:1 reduces internal tuner losses. This setting is best.1 Press [THRU/AUTO].• “– AT – TX” lights. If Menu No. 08 (RX AT) is ON,then “– AT – TX RX” lights indicating that thetuner is in-line while transmitting and receiving.In this case, prior to tuning in Step 2, receivedsignals are attenuated and the receiver sensitivityis lowered.• If the tuner has not adjusted itself yet for theselected frequency, then AT TUNE lights, andPreset tuning begins. Signals pass through theantenna tuner during this time. If Menu No. 08(RX AT) is OFF, the antenna tuner is bypassed.The AT TUNE light goes out when presetting iscompleted. You cannot transmit while presettingis in progress.• If Preset data exists, the next step cannot bedone until the transceiver completes the Presettuning.2 Press [AT TUNE].• To cancel tuning for any reason, press[THRU/AUTO] or [AT TUNE].• If the Preset tuning is aborted by pressing[AT TUNE], the new temporary data will be used,but this new data does not update the storedPreset data. Also, the new temporary data will belost if the operating band is changed. Return tothe stored Preset data by pressing[THRU/AUTO] OFF and then ON again.• AT TUNE lights and stays lit while the tunertunes. When the light goes out, the tuner hassuccessfully matched the transceiver to theantenna system with an SWR less than the valueset in Menu No. 33 (TUN.WIDE). You can beginoperating.• If tuning doesn’t finish within about 20 sec, analarm sounds. You may stop the alarm and thetuning by pressing [AT TUNE]. The alarm can beeither a triple beep or the Morse code “CHECK”depending on the Menu No. 37 (WARN. BP)setting.• After each successful tuning, the Preset data isupdated.Note:◆While receiving with Menu No. 08 (RX AT) ON onfrequencies outside the Amateur bands, sensitivity islowered.◆It’s a good practice to press[AT TUNE]after changing bandsto ensure the tuner has tuned for minimum SWR.AT TUNE7.49 ~ 10.4910.49 ~ 14.114.1 ~ 14.4914.49 ~ 20.9920.99 ~ 21.1521.15 ~ 21.9921.99 ~ 25.4925.49 ~ 2929 ~ 300.030 ~ 1.851.85 ~ 2.012.01 ~ 3.5253.525 ~ 3.5753.575 ~ 3.7253.725 ~ 4.494.49 ~ 7.037.03 ~ 7.17.1 ~ 7.49101112131415161718123456789Range(MHz)BandNo.Range(MHz)BandNo.