Kenwood TK-885 Service Manual

Also see for TK-885: Instruction manual Service manual

Contents

19TK-885SEMICONDUCTOR DATA / DESCRIPTION OF COMPONENTS Terminal function (TX-RX unit IC8)Pin No. Port Name Function1 STB ES Strobe2 SI DT DATA3 CLK CK Clock4 Q1 AM1 Audio mute 1. H : Mute, L : Unmute5 Q2 LOK No function6 Q3 STR VCO shift switching. H : TX, L : RX7 Q4 DM Dead mute. H : RX, L : TX8 VSS GND9 QS IC7 data output10 NC11 Q8 SQ No function12 Q7 CODE2 Option board data 2. H : ON, L : OFF13 Q6 CODE1 Option board data 1. H : ON, L : OFF14 Q5 OPT Option board control.H : ON, L : OFF / Auxiliary B.15 OE Output16 VDC +5V. Terminal function (TX-RX unit IC7)Pin No. Port Name Function1 STB ES Strobe2 SI DT Data3 CLK CK Clock4 Q1 HORN Horn alert. H : ON, L : OFF /Auxiliary A. H : ON, L : OFF5 Q2 HL RF power switching. H : High, L : Low6 Q3 TIMOFF Timed power off. H : Power off7 Q4 CODE3 Option board data 1. H : ON, L : OFF8 VSS GND9 NC10 NC11 Q8 W/N No function12 Q7 NC13 Q6 PA1 Public address 1. H : ON, L : OFF14 Q5 CODE4 Option board data 1. H : ON, L : OFF15 OE Output enable16 VDC +5VDESCRIPTION OF COMPONENTSTX-RX Unit (X57-6152-70) (A/2)Ref. No. Use / Function Operation / ConditionIC1 DC amp FC, TCXO controlIC2 DET amp External DEO, internal DEOIC3 Amp/Summing amp DI / DI and MO addtionIC4 Analog switch DI switchIC5 A/D converter PC, TV, FC, AFO, BEEP, TO, MOcontrolIC6 DC amp PC, TVIC7 Shift register HNC, H/L, TOF, CODE3, CODE4,PA controlIC8 Shift register AM, LOK, STR, DM, OPT, CODE1,CODE2 controlIC9 5V AVR External 5CIC10 AF power ampIC11 FM IF DET Quadrature detector, 2nd mixer,OSC, IF amplifier, RSSIIC12 5V AVR 5CIC13 9V AVR 9CIC14 8V AVR 8CIC15 Flip-flop Power on/off controlIC200 Mixer DBMIC300 PLL Reference 16.8MHz.PLL lock : LD “H”IC400 Power module RF power 25WIC401 Short protectionQ1 DC switch When PTT on CN1 is “H”,DI on CN1 is mutedQ2 Ripple filter 8CLQ3 Ripple filter 9CLQ4 HOR switch IGNQ5 HOR SW control IGNQ6 HOR SW control Active while HNC is “H”Q7 Buffer amp HTQ8 AF mute Active while AM1 is “H”Q9 AF mute Active while power switch is offQ10 8R SW control Active while T/R is “H”Q11 8R switch Active while Q10 is activeQ12 8T switch Active while Q13 is activeQ13 8T SW control Active while KEY is “H”Q15 IF amp 44.85MHzQ16 AF switch No functionQ17 PC switch Active while TXQ18 DET mute Active while KEY is “H”Q19 APC APC driverQ20 APC APC predriverQ21 APC controlQ22 TOF switch Active while TOF is “H”Q23,24 W/N switch No functionQ25 TOF switch Active while Q22 is onQ26 Inverter Active while power switch is “L”