Scott-320R-320RL-330R-330RL-Service-Manual 电路图 维修手册.pdf

《Scott-320R-320RL-330R-330RL-Service-Manual 电路图 维修手册.pdf》由会员分享，可在线阅读，更多相关《Scott-320R-320RL-330R-330RL-Service-Manual 电路图 维修手册.pdf（25页珍藏版）》请在收音机爱好者资料库上搜索。

1、ADJUSTMENT FM RF Tracking FM Signal Generator Scott 320R,330R/RL FM Equipment Required Audio signal generator. Level meter. Oscilloscope. Digital frequency counter, 0 -100 kllz. FM multiplex signal generator. Circuit tester, 20 kohm/V. Ant Out Dmmy Tape/Rec :zJ -o+-.u FM Ant 300Ohm Tf-:t:Q_-.S?:J-t-

2、.-t:Q. _ _J Level Meter Oscilloscope OJ Distortion Analyzer I) Apply 90 MHz, I kllz and 100% modulated, 65 dHf signal with 7 5 kHz deviation to the FM antenna terminal. (conected in parallel with the oscilloscope). 2) Tune the unit to 90 MIiz. 3) Observe the oscilloscope connected to the Tape/Rec ou

3、tput terminal for symmetrical sine v:ave. If failed, adjust T3. 4) Adjust Tl, and T2 for maximum level meter reading FM IF Amplifier 1) Mute the FM local oscillator by shorting CV3. 2) Connect oscilloscope to pin #13 of IC2. 3) Apply 10.7 MHz signal from the sweep generator to T2 in the manner as sh

4、own as above. 4) Adjust T4 for correct figure as shown. It may be necessary to increase or decrease the sweep generator output for adjustment convenience. 5) Readjust the signal generator for 106 MIiz, and retune unit. 6) Repeat step 3), if failed, adjust the trimming capacitor, ere. 7) Adjust the t

5、rimming capacitors, era and CTb. 1S446, etc. r - Correct 0.00/F I Oscilloscope Incorrect, as too low Incorrect, as too narrow RadioFans.CN 收音机爱 好者资料库 Tuning Meter 1) Remove signal generator output from the unit. 2) Adjust TS for exact center reading on the FM Center Tun- IF Distortion 1) Apply 98 MH

6、z, 1 kHz and 100% modulated, 65 dBf signal to the unit. FM Signal Strength Meter 330R/RL only) 1) Apply 98 MHz, 90 dBf signal to the unit. 2) Tune the unit for 98 MHz. Mute Circuit 1) Apply 98 MHz, 20 dBf signal to the unit. 2) Tune the unit (with the Mute switch in the Off position). Pilot Signal (

7、76 kHz) 1) Apply 98 MHz, 65 dBf signal to the unit with no modu- lation. 2) Adjust RV4 for 76 kHz reading on the frequency counter Stereo Separation 1) Apply 98 MHz, 65 dBf left channel signal to the unit modu- lated with 1 kHz, 9% pilot signal of 6.75 kHz deviation. 2) Connect a digital voltmeter t

8、o the right channel Tape/Rec output terminal. 3) Adjust RV3 for minimum leakage (minimum level) on the voltmeter. AM IF Amplifier 1) Apply 455 kHz sweep generator output to the unit AM antenna terminal. 2) Connect scope to the pin number 12 of IC3. 3) Adjust T8 to obtain maximum and symmetrical disp

9、lay as shown. AM (MW) Tracking 1) Apply 600 kHz, 30% modulated with 1 kHz to the AM bar antenna. See test setup figure (Distance between the AM bar antenna and emitting loop antenna should be 2 feet). 2) Adjust signal generator output so that a sine wave appears on the scope. 3) Adjust T9 for maximu

10、m audio output on the digital volt- ing meter. 2) Adjust T6 for minimum distortion on the distortion ana- lyzer connected to the Tape/Rec output terminal. 3) Adjust RVl for 90% reading on the signal strength meter. 3) Set the Mute switch to the On position. 4) Adjust RV2 so that the signal is muted.

11、 connected between TP and chassis ground. A deviation of 200 Hz is acceptable. 4) Apply 98 MHz, 65 dBf right channel signal to the unit modulated same as step 1 ). 5) Move digital voltmeter to the left channel Tape/Rec output terminal. 6) Adjust RV3 for minimum level. meter connected parallel with t

12、he scope. When turning core, always adjust signal generator output to maintain proper level. Do not change voltmeter range. Moreover, always keep the generator output as low as possible to avoid AGC action and to keep the measurements accurate. 4) Adjust the AM loopstick antenna core for maximum out

13、put RadioFans.CN 收音机爱 好者资料库 Scott 320R,330R/RL BA R ANT Tape/Rec 2J s AM Signal Generator Rad,ation 600kHz/1,400kHz Loop reading on the voltmeter. 5) Shift generator frequency to 1,400 kHz with same modula- tion condition. 6) Repeat 2). Long Wave Tracking 330RL only Bar Ant AM Signal Generator Radia

14、tion 170kHz/320kHz Loop I) Apply 170 kllz generator output modulated 30% with 400 Hz. See test set-up figure. Set two antennas in a dis- tance of 2 foot. Set the EXT antenna switch to INT position. 2) Adjust TIO and then long wave loop stick antenna core for maximum output from the speaker output te

15、rminal. 3) Shift generator frequency to 320 kllz with same modula- External Long Wave Antenna Tuning 330RL Only 1) Apply 170 kHz generator output modulated 30% with 400 llz audio. Set the EXT antenna switch to EXT position. 2) Adjust generator output to observe sine wave on the scope. Audio Adjustme

16、nt Out - :. ,_ - Level Meter Oscilloscope 7) Adjust CTe (CT5, 330RL) for maximum voltmeter reading. 8) Adjust CTd (CT4, 330RL) for maximum reading on the voltmeter. 9) Repeat above procedure again. 2J s Tape/Rec Out - - :. ;:; = = Level Meter Oscilloscope tion condition. 4) Adjust CT5 (paralleled wi

17、th C78) for maximum output from the speaker output terminal. 5) Adjust CT2 (On PSAZ024COX) for maximum output from the speaker output terminal. 6) Repeat above procedure. 3) Adjust Tl for maximum audio output. 4) Shift generator frequency to 320 kllz with same modula- tion condition. 5) Adjust CT3 f

18、or maximum audio output. Equipment Required Audio signal generator. DC vol tmetcr. RadioFans.CN 收音机爱 好者资料库 Bias Adjustment Speaker load resistors, 8 ohm, 100 watt. Digital voltmeter or DC milliammeter. The following adjustments are the same for both the left and the right channel. 1) Connect 8 ohm r

19、esistors to the speaker / terminals, and minals J K and J K, and connect ammeter, set co 100 mA range. set the Speaker A switch to on position. 2) Turn the Volume control fully counter-clockwise. Turn unit on and left it idle for at least one minute. Adjust RV7 for 40 mA. 3) Turn RV7 fully countercl

20、ockwise. 4) Depending on available equipment, use A or 8 : 5) Perform the same procedure for the right channel, except measure voltage across R220 and R222 (voltmeter bias test points, R channel) or replace jumper from J L to J L with ammeter. Adjustment is made with RVS._ A. Set digital voltmeter t

21、o most sensitive voltage range. Connect probes across R219 and R221 (Voltmeter bias test points, L channel). Turn unit on. Let it idle for at least one minute. Adjust RV7 for 40 mV across the resistors. 6) Leave the amplifier on for about 30 minutes, then recheck measurement. A tolerance of 25% is a

22、cceptable. Re- adjust if necessary. B. With unit off, remove jumper between PC board ter- Dial Cord Stringing 1) Loosen the screw securing the drum to the variable capa- citor shaft. 2) Tie the end of the cord A as shown to the fixing pro- trusion on the drum. 3) Wind the cord two turns around the d

23、rum then thread it through the rollers, etc, following the illustration. 4) Tie the end of the cord to the coiled spring so that the pro- per tension of the dial cord is obtained. 5) Align the pointer position for the correct frequency indica- tion on the tuning dial. 6) Secure the screw on the drum

24、. Adjustment Location Voltmeter Bias Test Point , + ) ,f2,;,1 -: a l 6v A;.-I (C!9B .,: 1E a * 1it T - ii- 112 L-=-OJ .-i: 161 -c-lL . -w -,p C!06 L) - I ._.JL . .:.) C!l2 . (1l: -I -it=-a,o-0-i.:io .V :,: _ Al08 -C104 1io1J20_: _ _A_l_l6-e Rt iJJWo I : -,; * Q R125 o: -JJ er. S V 2 - R65 ,-JM- + r-

25、 -r- -, i Ri? -t -nEJ4 J.U- : T4 -4pl 1 - Rt_ f ,r -11_, . I ,!J JJ6 - - -,.i -i_.lb7 I Cll)j ,35 -_ , -i (f) /j: L-=:._ u3 I A22S -, , - Left Channel r:- . c N Right Channel _.,. )5 i=.-=- fi1f . - _j ! 3 . . ( -_I H8:!: .,._.,.:,.,. -,-.- - i-1 -r;: . zrz S, - - I I c174 r: 1 . S OTT o R- . I-I .:

26、, 0 1 u ft21.o_2_ I 8, O.L+4-. i) C . n, _ fa,QO_ In ! AP AOOlBO as - -l 1 lfZ, 1 c -0 1 . =-=-+t-=-ff-02 R)4 I -_ij2_yl f(X.J fllY8 l ! I 1111 I.DUD CS9 - -., - t CS6 , , )._ C :0 -=62. .! - 0 : D27 QC If I o:r:I / . , J.2 1 _,.-, RV6 -f I -I,css n 0 - - . :o C ;e :0 r- BLOCK DIAGRAM 330R / RL / 32

27、0R -1- -I r ,; mo 1 I ,- CFI _ -MF/T:N- -7 I -I -I I = ,.-.I -T FM ANT 300fi CVI tsn Cl LI I I -I I _ I I AM TUNER IC I r o. 1 IF AMP k ICI 2 CF3 r I7:l ., MUTING CONTROL I = TT MUTE ON r- 19kHz/38l:5 I lt159 12 1!12-1 I 21 Jli 04 2SO526 L _ Ql!S,16,17,18 2$C2240 !GR.BL) 1 .;g: 1 y;:; -j ;it ,MJ.:To

28、1:t2,t NOTE. All VOLTAGlS ME.ASIJREO FROM COMMON N(GATIVE Cllti.SS,1$ GROUIJO NITH VTVM AT NO SIGNAL 2 CAPAClJS Vt.1.UE:S ARE IN JF UN!.ESS OlHffiWlSE NOHU P:;Q Fl.RAO J RESSTORS VALUES ARE IN OHM I 2SA970 2SC220 2SC22401BLI 2SA97018LI IGR,BU COft,ILI re, ECO ECO 044 250526 , 019,20.21,22 2SC220 CGR

29、.8U 045 2SK 30A lGR I ,sc CO , l LI . . , 2SCl815 lY,GR) : :;:l 0 25 ,26 . 2SA7Hll,GI .7K 027, 21 2SCIJllfO,Y) :.! , . vz, ilUO . 2SCll15 IY.G) . . ., 1s1, en /so 0 29 . JO 2SCISll (O.RI OJI ,32 ZSA7ZO 10.ltJ 1111, 112w on ,J 2SCIJll(Q,ft) 0 35. , 2SA7ZO 10,lt) 201 ,. l/2W 017 ,JI 2$C18ZIIO,YI 039.4

30、0 2547110,Y) . . ,. I l.:.: . : i $: . . - JI fHONU i :, : ,- r_._J! 1,s ,s . .J . . 111 t. 251( JOA IGR) 2SKJOA IGR) cc:, ;, r;:-: JI I ; ,. ?.P 1 .: I : 1111:_-:-; - - -,-.- _ _ _ :.J flt.2 ., . %, JJU) I t:, -n . ; = . - -.,i. .J-0 : . , . 1 . :._ .:_ _ r,1;. : fl.,. -, . ,fil -(, r,; , , 1 ,. ,

31、._ -=:t:=:.c:, : LI LI J PSAzOz G I - . . 2SClll5 IY,GIU Cl OU,2 2SA7HIF,01 02:7,21 25Cl318CO,YI Cl 029 .JO ZSCI S 1810,lU ca - JS OJI, 32: OJJ,34 ZSA7ZO 1O,R) ZSCIJIII0,10 CCI CCI 015.:H ZSA72O10,R I 037 ,H o,. o 2:u.1,1 fO,YI y . -.-f4-. STY JH SCHEMATIC DIAGRAM: 320R J 7 I PSAA004CO X F M INTERNA

32、L vvv -A, FM 3000 f- FM 750 L AM I Tl :,-., -2)-+.) , . R2 L!h-t-, J AUX , , ti C95 .0 4 7 G G I I 0 PHONO 0 MUTE 0 0 0 AUX F M MW - en .01 -: I TAPE I S 3 I I IC 3 J2o REC R9$ 2.ZK - I I I I r-0-.: _._-R,-.JJ J I PLAY R97 3901( I C96 ,047 , R96 2.2K R96 3901 -0 - Lo - - Lo - -I I I I I s21 I 013,14

33、 2SA970 IGR,BU - I o t . TlRIOI Ol 100K 100K . - .,. HA II 97 I l - 02 2 SC535(8.CI li ECB 03 2SCI 923 (0.RI li Ece NOTE I ALL VOLTAGES MEASUREO FROM COMMON NEGATIVE CHASStS GROUND WITH VTVM AT NO $1GNAl 2 CAPAC.i0AS VA.UES ARE 1N F VNL.E.SS OTH.ERWISE NOtfO .,.,_ PiO Ft.RAO s .AES1STORS VALUES ARE

34、IN OHM K=KOHM 4.VOLTAGE-S 1111 )WHEN MUTE ON 5 VOLTAGES IN WHEN AM 013,14 2SA970 IGR,BU li CB 0 15,16,17,18 2$C2240 IGR,BLI i CB 042 2SC22401Bll 043 2$A970 IBU i r.ce 044 2$0526 010 011 04 05 2SC224018,Ll 2SCl815 Y.GR) 2SCl92310.RI 2SC 1815 (Y.GR) EC8 0 19 ,20.21,22 2SC2240 !GR.BU Ece li ECB 045 2SK

35、 30A IGR I li EC8 04 2SCl92310.R) C36 16 R39 47K rlf-.-1- .-,v.-C42 , tt46 R44 4,1/zs 47 _,J, 4,7K 4.7K 019,20,21.22 2SC2240 (GR. BL) 3 4.7t-Rv2. OO . 0 25 ,26 2SA7981F.G) 0 27, 28 2SCl318IO,Y) R21 33K . 03 1S1555 11r Cll .47/50 05 2SC 1815 IY,GR) 0 29 30 2SCl318(0,RI 031, 32 2SA720 10,RI 0 33, 34 2

36、SCI 318(0,R) 035, 36. 2SA720 10,R I 041 2SCl815 Y.GR) 0 25 ,26 2SA7981F,G) 027,28 2SCl318(0,Y) Q 29 30 2SCl31810.RI 031 , 32 2SA720 10.R) i CB li (CB li ECA - R24 470 ,- R25 ,u en - ho 05 1S1555 J 0 37 ,38 2SCl82610,YI 0 39. 40 2$A768 I0,Y I Pt 0 tg RH 27K ) Q 33, 34 2SCl31810,RI 0 35. 36 2SA720 0.R

37、 I li CB - - I 037 ,38 2SCl826 I0,Y I 0 39. 40 2SA768 10,Y) . M l Ml151 RAil K I . . . s rv . J H ,.-, P I N L _ ,.,. _ J t ,. _,; k Scott 320R,330RIRL (PartS Location Diagram Continued) N- HW ill f!JS( , , 0,. s . V , I . . , I : (f. vs l. - - - 02 01 1SC!H511,C) ZSCIHSCOJU Ylt2 X-8 04 ZSCl92310 ,J

38、tl 0 19 ,20 021,22 2SC224 0 ZSCZUO 18L) !GR.au -+tt-. Rr,., 1111)7 l 2.C C ,u - I l- . . 013.14 2SA10 !GR.Ill 015,15,17,11 2SC2240 IOR,ll I 27Cl:Jf lll)J, c.i, , . RISI RI t 2 - 2, ;c;.,ct , 011 12M 9 21 1t1, 11,1s: ,zK ! M 041 2SClll5 -r- IY ,GIIU 1Ul8 021 22 1s1sss 045 2SK30A 1 l . RESISTORS VALVE

39、S ARE IN OHM I 2SCl92!10Jtl $CU41018LI SA970 IBLI S052610.Y) 04 Z5Clt2510,1U 01,20 021,22 2SC2240 2SC22410 ( IL) IGlt,BLI . , . c., 41/,5 CP. o, , . .,. . lllt 1121 , OJ l .t!C U!C 1S1 0. 2SCll15 IV.lift) 02,.zt 02,.,0 o,.,. 2$A1U 1,.01 2SCl518l0.RI 2SCIU7A 10,YI 027,21 031,2 05,. lSC222tlYI 2SA 720

40、 10,ltl 2SA 117A 10,YI r;:=:;-.;:=!7 t: : lf2W c1, c11, o 2SAl018 l!,UI ,- OJ1,51 2SC1tlll0.Y I 0,1.o 2S.t.771 fO,YI I ;:.: I I I L_l I lH-o.,- ,+-+-=CCCF:.-+-14-*+-.-+I-. H 0 lt 2tlI 1s, I IICIIHlO,YI ,o, , )r , OH.40 ZIA7U 10,Y I a -_ j 01/o )f , 111,20,21,22 045 041 0 25 ,21 027, 21 0 2t . SO 011

41、 .u on,. OH ,If 2SC22410 2SK 30,. ii!SCI 11i, 2SA7Hl.G) ZSCISIIIO,YI 2SCISIIIO.ftl UA1ZO 10,ltJ IICIIIIIO,ft) 2SA7ZOIO.ltl IOlt,ILI IGltl ll,Gftl R 1r CCI H:e (Cl cca (Cl CCI 5 TV ,_, ,-, r , . JOO() 1- ,1111 750 L IAI rt L- Jl O EC , . P HONO r ,s .047 , PSAA004COX 0 0 0 0 0 . l90K Lo - 015,16,17,1

42、8 1 2SC2240 SCHEMATIC DIAGRAM : 01 3SK 73(YI GI - - y I I s/ I I I I HA 1197 _ . ,.,.-I Rl$1 ,. $41 I I I I a. ? 02 Z SC535(9.CI i CB C79 .047 I R, ,3 c,21,l 680 220 ON 03 ZSCl9230.RI )i CB L (GR.BL) - 330R 010 011 04 2SC224019.LI 2SCl815 IY,GRI 2SCl92310.RI CO2 022 i )i CB 04 2SCl923!0,ltl 019,ZO 2

43、SCZ240 (8 L J 021,22 ZSC2Z40 IGR,BLI 1C HA1137W 025, 26 2SA 198 IF.GI 021, 28 2SC2229(YI Ffl87 410 . 025 , 7 r., R19 Cl6l 82i U OP Rl91 39 029, 30 2SCl318l0,Rl 031, 32 2SA 720 10,Rl ,.2v 05 ZSCl815 Y,Gl!I 05 2SCl815 IY,GR J 033,34 2SCl627A (0,YI 035, H 2SA8l7A 10,Yl o ZSA 10111 CY.GR J o 151$ l()te

44、.I. C32 - ,. o, 031,38 2SCl9HIO.YI 039,40 2SA 771 (0,Y I ft2f3 A221 220 .47 R209 112 2W l.31S AA-IZ +re,., . tl/,o, -+- -+-.RZOZ 034 38 (184 RZOO l ,7, l ,51( 112# I IZW I. V. a6 1/50 .,.,.,.,+-,.,-c1H-I RZO 0 20 c,eo o, 27 1 51555t-4100P. ,_RAll R216 210 l. 6 19.,/ R208 2 5JtH ._.,. .l,31 R212 R22(

45、 220 .47 RZl 112W ZW .6 I/ 2W J2 Ml $ 1GNAl METR - ) , . ,. ).5A OS7 ,Se 2SCl8H(O,Yl 0 . 40 2SA7S8 IO,Y I NOTE: I . ALL VOLTAGES MEASUREO FROM COMMON NEGATIVE CHASSIS GROUND WITH v TVM AT NO SIGNAL. L - -J 2. CAPACITORS VALUES ARE IN ,F UNLESS OTHERWISE NOTEO P PISO FAR Av 3. RESISTORS VALUES AR IN OHM K =KOHM -l. VOLTAGES IN r ) WHEN MtJTE ON 0 44 S. VOLTA