Kenwood TK-280 Service Manual

Also see for TK-280: User manual Instruction manual Instruction manual Pricing and specification manual Service manual

Contents

TK-28044Test Moden Test mode operating featuresThis transceiver has a test mode.To enter test mode, press[B] key and turn power on. Hold [B] key until test channelNo. and test signalling No. appears on LCD. Test modecan be inhibited by programming. To exit test mode, switchthe power on again. The following functions are available intest mode.• ControlsControls “SFT” appears “SFT” not appears[PTT] Used when making a Used when makingtransmission. a transmission.[AUX] Unused Unused[MON] Shift OFF. Monitor ON and OFF.[CALL] Lights the lamp for five Changes wide, semi-seconds. wide and narrow.Lighting is extended fora further five seconds bypressing any key whilethe lamp is lit.[A] FFSK 1200bps Sets to the Tuningand 2400bps. mode.[B] Shift OFF Shift ON.[C] Compander function RF power HIGH andON and OFF. LOW.[D] Best shift ON and OFF. Changes signalling.[O] to [9], Shift OFF Used as the DTMFand [#],[∗] keypad. If a key ispressed during trans-mission, the DTMFcorresponding to thekey that was pressedis sent.[ENCODER] Changes channel. Changes channel.Note: If a [A],[B],[C],[D] key is pressed during transmission,the DTMF corresponding to the key that was pressed is sent.• LCD indicator“SCN” Unused“ ” Lights at Compander ON.“LO” Lights at RF Power Low.“P” Unused“MON” Lights at moniter ON.“SVC” Unused“ ” Lights at FFSK 2400bps.• LED indicatorRed LED Lights during transmission. Blinks at the lowbattery voltage warning.Green LED Lights when there is a carrier.• Sub LCD indicator“SFT” appears at Shift ON.n Frequency and signallingThe set has been adjusted for the frequencies shown in thefollowing table. When required. re-adjust them following theadjustment procedure to obtain the frequencies you want inactual operation.Frequency (MHz)Channel No. E, TRX (MHz) TX (MHz)1 160.05000 160.100002 146.05000 146.100003 173.95000 173.900004 160.00000 160.000005 160.20000 160.200006 160.40000 160.400007 ~ 16SignallingSignalling No. RX TX1 None None2 None 100Hz Square3 QT 67.0Hz QT 67.0Hz4 QT 151.4Hz QT 151.4Hz5 QT 210.7Hz QT 210.7Hz6 QT 250.3Hz QT 250.3Hz7 DQT 023N DQT 023N8 DQT 754I DQT 754I9 DTMF DEC.(159D) DTMF ENC.(159D)10 None DTMF tone 911 2Tone (321.7/928.1Hz) None12 Single Tone 1200Hz Single Tone 1200Hz13 5Tone DEC.(EIA #12345) 5Tone ENC.(EIA #12345)14 FFSK(1:1 Pattern)15 FFSK Code FFSK Code• Preparations for tuning the transceiverBefore attempting to tune the transceiver, connect the unitto a suitable power supply.When ever the transmitter is turned, the unit must beconnected to a suitable dummy load (i.e. power meter).The speaker output connector must be terminated with a16Ω dummy load and connected to an AC voltmeter and anaudio distortion meter or a SINAD measurement meter at alltimes during tuning.• Transceiver tuning(To place transceiver in tuning mode)Channel appears on LCD. Set channel according to tuningrequirements.ADJUSTMENT