background image

MAINTENANCE 

SERVICE  MANUAL 

FT-2.08R 

YAESU 

YAESU  MUSEN  CO.,  LTD. 

C.P.O.  BOX 

1500 

TOKYO,  JAPAN 

YAESU  ELECTRONICS  CORP. 

P.O.  BOX 

49 

PARAMOUNT, CALIFORNIA, 

90723 

-

•. 

\

Summary of Contents for FT-208R

Page 1: ...MAINTENANCE SERVICE MANUAL I FT 2 08R YAESU YAESU MUSEN CO LTD C P O BOX 1500 TOKYO JAPAN YAESU ELECTRONICS CORP P O BOX 49 PARAMOUNT CALIFORNIA 90723 I...

Page 2: ...GRAM 2 1 CIRCUIT DESCRIPTION 2 2 CRYSTAL DATA PLL CIRCUIT FREQUENCY RELATIONSHIPS 2 4 SECTION 3 SERVICING OUTER COVER REMOVAL 3 1 EXPLODED VIEWS 3 2 SIGNAL LEVEL DIAGRAMS 3 5 MAIN UNIT PARTS LAYOUT 3...

Page 3: ......

Page 4: ...and drawings are utilized liberally Use of this manual is entirely at the owner s risk The FT 208R uses high quality compo nents and a design and construction intended to last a long time without the...

Page 5: ......

Page 6: ...1 2 SEMICONDUCTOR COMPLEMENT ACCESSORIES AND OPTIONS 1 3 TOP PANEL CONTROLS AND SWITCHES FRONT PANEL SWITCHES 1 4 BOTTOM PANEL CONNECTIONS 1 5 INSTALLATION 1 6 BATTERY CHARGER INFORMATION 1 7 SPEAKER...

Page 7: ......

Page 8: ...eby a favorite segment of the band may be scanned instead of the entire band The FT 208R may also be programmed via the keyboard to exclude a given section of the band if desired Digital display of th...

Page 9: ...147 995 144 000 145 9875 144 000 147 9875 1 44 000 147 995 1 44 000 147 995 144 000 145 990 PRESET FREQUENCY MHz 147 000 145 000 145 000 145 000 147 000 145 000 TRANSMIITER Power output 2 5 watts HIGH...

Page 10: ...1 2SK 1 84Y 1 HZ6B l L Zener 1 2SK 1 92Y 1 LCD Display HZ7A 2 Zener 1 2SK 1 93K 3 HI30 1 HZ7B 1 L Zener 1 SG235D LED 1 SR53 5D LED 1 Model B C D E only ACCESSORI ES AND OPTI ONS YHA 1 4 Rubber Whip A...

Page 11: ...This switch selects the repeater transmit frequency offset desired In the SIMP position the transmit and receive frequencies are the same Shifts of 600 kHz and auxiliary splits SET can be selected Wh...

Page 12: ...the STOP mode of the scanner STEP This switch selects the desired synthesizer step When this switch is set to the X2 position 10 kHz 25 kHz steps are programmed When not in the X2 position 5 kHz 12 5...

Page 13: ...apply AC power of any kind nor DC voltages above 1 3 volts as these types of abuse will void any factory warranties The following procedure will allow quick changing of battery packs LOCK OPEN 1 6 Fo...

Page 14: ......

Page 15: ...tely charged The DC adapter function of the NC 8 can be used to operate your FT 208R while saving battery consumption During operation with the DC adapter the charger function can also be activated NC...

Page 16: ...GENERAL FBA 2 NC 8 NC 8 FT 208R NC 8 FBA 2 FNB 2 _ r eeae NC 9B for 117V AC NC 9C for 220 234V AC 1 8...

Page 17: ...02 _ _J 001 AC 234 v AC 220V AC 200V AC l l OV I AC 117 v POWER TRANSFORMER PRIMARY CONNECTIONS 0 SO NC 7 r r 001 2SD23 Y 004 004 2SC 94 K F2A NC 8 258633 2SCl383 0 t N PA 3 1 9 IW 27 2SC94 RLOI NOTE...

Page 18: ...alled the YM 24A can be held close to your ear during reception allowing you to raise your FT 208R high above any obstructions On transmit hold the microphone near your mouth and squeeze the switch on...

Page 19: ......

Page 20: ...now operating on 146 025 MHz 1 1 l 3 Let s try another example To operate on 147 725 MHz press 7725 and DIAL Models B and C 1 When a frequency is programmed from the keyboard the four digits above 1...

Page 21: ...built into the FT 208R To select the shift frequency set the SHIFT switch to either the RPT or RPT position 1 1 2 2 When nonstandard repeater shifts other than 600 kHz shifts are required the repeate...

Page 22: ...ning function will repeat itself until you stop on a specific frequency 1 1 3 GENERAL Note The following frequencies cannot be program med as band edges for the limited band scanning function Model A...

Page 23: ...purposes the two tone DTMF encoder can be activated from the keyboard by pushing the PTT switch and dialing the required access codes and tele phone number For installation information regarding the...

Page 24: ...SECTION 2 TEC H N I CAL NOTES BLOCK DIAGRAM 2 1 CIRCUIT DESCRIPTION 2 2 CRYSTAL DATA PLL CIRCUIT FREQUENCY RELATIONSHIPS 2 4 __...

Page 25: ......

Page 26: ...I 012 1 I I 2S 2 85E 0 2 1 9 2SC2785E 7 V R E G 0 2 0 7 2SK1 84Y B UFF 0208 2SC2785E L P F 0 2 I 2 2SC2785E 5 6V REG I I I I 011 7 2SAI 175 E s w DIOI Dl02 Ml 3 0 1x2 s w 01 2 2 2SC2785E s w PA AMP 0...

Page 27: ...5E such that DC voltage is removed from AF amplifier Q114 thus silencing the receiver 2 2 When a carrier is present in the 455 kHz IF the noise is removed from the discriminator output and Q 114 is th...

Page 28: ...llator frequency is controlled by varactor diode D201 1T25 which varies the capacitance of the oscillator tuned circuit in accordance with a control voltage This control voltage is generated by phase...

Page 29: ...5MHz c 127 I 131 0875MHz F 127 1 129 09MHz 0210 0201 0202 2SC2786L 2SK192Y 2SC2786L BUFF vco UFF 0207 0208 2SKl84Y 2SC2785E Bl FF LPF TYPE X201 A D F 5 76MHz B C 7 2MHz CONTROL UNIT TYPE DIVISION RATI...

Page 30: ...UT 3 7 PLL UNIT PARTS LAYOUT 3 8 PLL UNIT VOLTAGE CHART 3 9 LEVEL DIAGRAM PLL SECTION 3 10 CONTROL UNIT PARTS LAYOUTS 3 11 WIRING DIAGRAMS 3 15 MODIFICATIONS FREQUENCY RANGE AND LOW POWER 3 18 MAINTEN...

Page 31: ......

Page 32: ...em No 1 2 3 4 5 6 7 8 9 10 1 1 1 2 Nomenclature Rear Cover Battery Cover Belt Clip Flat Head Screw M2x1 0 Flat Head Screw M2x16 B U Switch Label Clip Screw Logo Plate B FT 208 Model F Logo Plate C FT...

Page 33: ...te 2 14 PLL Shield A Pad R7069730 2 1 5 PLL Shield Case R0066890A 2 16 PLL Shield Cover R0066900B 1 7 Coaxial Jack P0090187 1 8 Mini 2 Conductor Jack P1090 127 19 CH Jack Cover R7066940 20 Bottom Pane...

Page 34: ...e Light 22 Switch Top Burst 23 Knob FT l ON Shift 24 Pan Head Screw 25 Stop Ring NOTE 1 FT 208R Model A F NOTE 2 FT 208R Model B C D E NOTE 3 w Switching board NOTE 4 FT 208R Model A F are PTT only Ot...

Page 35: ...L R3066870 4 LCD Unit G6090021 2 Knob FT lOS SQL R3066870 5 Contact Strip S200001 4 3 Knob FT lON Shift R3066860 6 Spacer S200001 5 4 Set Screw Supplied w FT lON 7 Diffusor S6000043 5 Cap A MIC EAR R3...

Page 36: ...LECTOR Ql05 0105 BASE COLLECTOR Ql06 QI06 BASE COLLECTOR QIOB QIOB BASE COLLECTOR Vrms 1 5 J jL OdBu 0 5uV I I I I I I I I H I I B G I r j I 0 I C I Jj_ I 14 5MHz 16 9MHz 455kHZ __J 0 5 0 1 0 p QI09 P...

Page 37: ...DIAGRAM TRANSMITTER SECTION A 0217 PIN 2 0217 PIN5 VR202 VR202 0213 0214 HOT END CENTER COLLECTOR DRAIN C D r I I I I E Vrms 2 I _ I I I I I I I I I G BPF BUFF J 0216 0101 0 101 BASE BASE COLLECTOR J...

Page 38: ...7 6 8 0 RX Ql06 2 3 3 7 1 6 RX Ql07 1 5 1 6 0 9 RX Ql08 6 4 7 8 5 7 RX 0 6 0 0 05 1 0 3 0 RX Q l l O TONE SQ SQ TIGHT 10 8 0 10 8 RX Ql l l 10 1 10 3 TONE SQ SQ TIGHT 0 6 0 0 02 0 06 0 RX Ql l 2 TONE...

Page 39: ...wed from component side 3 8 I e II Viewed from solder side COL LECTOR EM ITTER I BASE 2SC2785E 2SC2786L SOURCE GATE 2SK1 92Y l__JP I N 1 PC577 H P I N 1 1 GATE SOURCE 2SK184Y SOURCE DRA I N 2SK1 93K P...

Page 40: ...1 4 2 4 2 6 Q220 8 9 0 0 SEMICONDUCTOR REPLACEMENT Location No ORIGINAL REPLACEMENT PART NO PART NO Ql l O 1 1 2 1 13 2SC2785E 2SC2785F 1 1 8 121 1 22 208 2 1 1 2 1 2 219 G3327850E G3327850F Ql l l 1...

Page 41: ...02 BASE COLLECTOR ror 650mVrms dBm 10 0 OdBm 0 2236V 8 I It I 1 I l e A HIGH 146MHz 1 DN TONE IN E D 3 1 0 PLL LOCAL IN 0203 EMITTER 0203 0203 BASE COLLECTOR TONE l l mVrms BURST 50mV rms R260 0204 02...

Page 42: ...P I N 8 PIN 7 MC1 40698 M K5087 P I N 1 3 1 1 SERVICING When replacing the Backup Lithium Battery never allow your skm to touch the battery as the battery will pick up oil from the skin and thus have...

Page 43: ...SEG3C SEG4A SEG4B SEG4C SEGSA SEGSB LCD DRIVER PIN NO 1 8 1 7 16 lS 14 1 3 1 2 1 1 Q302 CONTROL U N I T PARTS LAYOUT Prod Lot Seriol N o 07000 1 U P Viewed from CPU Q301 side CONTROL UNIT VOLTAGE CHA...

Page 44: ...Normally H BUSY STOP STOP L CLEAR STOP STOP H KEY E ROW OUT Normally L KEY ON LCD DRIVER STROBE Normally L LCD DRIVER ENABLE Normally L GND KEY A ROW OUT Normally L KEY B ROW OUT Normally L KEY C ROW...

Page 45: ...03 0 I I sv _Jr HLT SIGNAL JL DELAY TIME 6mS PIN No PORT FUNCTIONS WAVE FORMS l D l DATA INPUT l Normally H 2 STD STROBE Normally L 3 CE CHIP ENABLE Normally H 4 FC FLAME CLOCK 0 6mS 5 Vss LCD DRIVING...

Page 46: ...z r 2 t a t c z a BURST B C D E ORG S 03 4 lj5 M IC DI fX TX to J02 P IN3 lcEXTPTTl BLU to J02 P I N I e to POI 246 to JOI CTONE SQ IN SHIFT S02 S P BRN SPO I I COMPONENT SIDE I SET V I M GRAY A B C D...

Page 47: ...a C 0 z a BURSTCB c o E ffiG 503 3 4 M IC 9 w LAMP 503 10 to J02 PIN3 iCE T PTT I BLU to J02 P1NI to POI to JOI CTO E SO IN SHIFT SP BRN SPOI I COMPONENT SIDE I Serial Nos 07000 1 S UP 0 I M 4 A B C D...

Page 48: ...C r i VJ I M a CJ c CJ z a WHT 5 3 2 POI A B C D E Type SP BLU GRN EAR HI LOW ff I ANT GRAY SHIELD BRN l l j I i J t t w YEL F Type I T I 1 I I 1 il t J03 l SOLDERSIDEJ GND CHG r I M...

Page 49: ...dicates that a jumper wire or resistor should be installed TypeF 144 0 145 99 145 0 10k 20k x x 0 Carbon film 1 8W 5 6kQ Carbon film 1 8W 5 6kQ 2 Some models use a resistor between the points indicate...

Page 50: ...T201 for a reading of exact ly 1 5 volts on the voltmeter 3 1 9 4 Now set the transceiver to 1 47 995 MHz 1 45 975 MHz or 1 47 975 MHz and check to see that the DC voltmeter shows more than 5 5 volts...

Page 51: ...OPE 2 Adjust the cores of T105 T106 and T101 until a minimum distortion pattern and maximum output are observed on the oscilloscope B RF Coil Adjustment 1 Set the transceiver frequency and signal gene...

Page 52: ...SERVICING T202 T2o3 T2o9 TC201 T2os T201 T201 Q205 VR 201 Q208 T2o6 T2o5 0219 T2o4 PLL SECTION ALIGNMENT POINTS 3 2 1...

Page 53: ...Align ment Point photo on the next page T101 T102 c 3 Set the HI LOW switch t o the LOW position and close the PTT switch Now adjust T204 T106 T107 T20s T109 and T110 for maximum DC voltage on the met...

Page 54: ...er Audio Osc i l l ator Figure 2 P O Meter 0 Ose i I lo scope TC101 iiiiiill T209 T2os T201 ii iii if l s i i i i T204 T2o6 r VR202 i j I to TRANSMITTER SECTION ALIGNMENT POINTS 3 23 SERVICING LCD 030...

Page 55: ...SERVICING Q205 Q205 Q207 Q2os Q212 Q211 3 24 CONTROL UNIT PB 2205 KEYBOARD ASSY Q301 Q304 Q106 Q303 Q302 Q115 Q116 Q114 Q217 Q215 Q219 Q21s Q214 Q215 Q210 Q213 D209...

Page 56: ...der tape to ensure a professional repair job 5 If you do lift a trace don t worry Read on to find out how to repair traces like a pro NOTES ON USE OF CMOS IC S As CMOS devices are extremely sensitive...

Page 57: ...cleanly 5 Remove iron from work Do not apply more heat than necessary for good solder flow Soldering to terminal posts Be certain to apply heat to both post and wire 3 26 EXAMPLES OF POOR SOLDERING P...

Page 58: ...c Phenolic Glass The Base Material Double Sided Board C Z YP1 t o Phenol o GI The component side is always opposite the solder side even if both sides Edge Connector Area are plated Z wire used to con...

Page 59: ...ailures caused by improper application of supply voltage or by voltage spikes An improper fuse in use could cause extensive damage to be sustained c Improper operation e g transistors without load thi...

Page 60: ...ve power Component burned Aging Value changed High temperature Open circuit Potentiometer Excessive power Component burned Shock Open circuit Noise Unsmooth rotation Capacitor Excess voltage Shorted H...

Page 61: ...1 0V 5 6V Check AF voltage at pin 9 of 01 09 YES NO NO NO NO NO Y ES 3 30 Check battery and battery terminal F201 J201 Check 01 20 01 2 1 01 22 and associated circuit Check 021 2 and associated circu...

Page 62: ...at emitter of 01 07 YES Check emitter voltage of 0108 N O N O 3 3 1 SERVICING Check 021 0 and associated circuit Check 0201 021 9 and associated circuit Check 01 07 and associated circuit Check 01 04...

Page 63: ...SERVICING TRANSMITTER 1 No modulation on TX NO OK Adjust VR202 O K NO N O 3 32 Check M01 and associated circu it Check 02 1 7 and associated circu it Check 0208 0209 and associated circuit...

Page 64: ...associated circuit SERVICING Check 02 1 3 X203 T206 and associated circuit Check PLL circuit Readjust T207 T2 1 0 Check collector voltage of 0101 and check 01 01 Check collector voltage of 01 02 or re...

Page 65: ...SERVICING 3 Unable to transmit LOW LOW 5V H I G H 5V H I G H 3 34 Check 0120 1 2 1 and associate circuit Check CONTROL U N IT...

Page 66: ...SECTION 4 REPAI R PARTS ORDERING FORMS 4 1 PARTS LIST 4 5...

Page 67: ......

Page 68: ...our parts department of the item you require See example below Shipment of parts from Yaesu USA is usually made by UPS COD Allow at least a week for the parts department to process your order You will...

Page 69: ...4 2...

Page 70: ...________ State _ _ _ _ _ Zip _ _ _ _ _ Country _ _ _ _ _ _ _ _ _ c ut here Y AESU M US E N CO M PA N Y LTD C P O BO X 1 5 00 TOKYC JAPAN Y AESU E LECTRON I CS CO RPO RATION P O Box 49 Paramount CA 907...

Page 71: ...4 4...

Page 72: ...0 1 1 2 1 1 3 1 1 8 1 2 1 1 22 Q105 Q106 108 0 108 109 0 1 06 0101 102 0107 XlOl X l O l XFl O l CFlO l 1 02 Rl61 162 R 1 1 2 R109 R169 R 1 04 R156 R 1 3 3 R l 6 0 R148 R 1 07 159 R 1 72 Rl7 1 R l O l...

Page 73: ...C152 K701 27225 Tantalum 16WV 2 2 F CS15ElC2R2M POTENTI OMETE R C159 K70127475 4 7 F VRlOl with SlOl J60800091 EVJ LKBP 15A24 20KnA CS1 5ElC4R7M VR1 02 with S 1 02 J60800090 EVJ LKBP 15B53 5KnB Cl 1...

Page 74: ...R26 1 R239 25 1 258 R222 224 R21 0 225 232 240 254 R255 256 263 R204 R216 R253 R264 R235 R226 R237 R236 252 R238 262 R201 247 R233 246 R218 220 250 R260 R206 209 R214 R242 245 249 R228 23 1 R203 R2 1...

Page 75: ...K l 9 149013 X O Ol F 295 297 UAT05X103K L05AE TP TERMINAL C281 282 K l 91490 1 9 25WV X 0 033 F Q5000036 TP G UAT08X333K L45AE C274 K23 1 70006 sowv 0 047 F C0301 0303 03 1 3 K23 140005 RPF 1 1 2C473...

Page 76: ...21 5684 VJ 680kn 10121 5824 TJ 820kn 1002 1 5 105 VJ l Mn THE RMISTOR G9090016 330 28 CAPACI TOR K101 8647 1 Ceramic Disc 63WV B 470pF RD870 1B47 1 K63V K l 0186102 O OO l F RD870 1B 1 02K63V K l 9149...

Page 77: ...M EMO 4 1 0...

Page 78: ......

Page 79: ......

Page 80: ...YA E SU v E 3690 982AC820 5 N...

Reviews: