Marantz-2245-rec-om维修电路原理图.pdf

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1、Model 2245 Stereoohonic Becdiver RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 rrr-roArnt- Model 2245 Stereoohonic Recriiver MARANTZ CO, INC.P.O. BOX 99.SUN VALLEY CALIFORN IA.91352 A WHOLLY-OWNED SUBSIDIARY OF SUPERSCOPE INC., SUN VALLEY CALIFORNIA 91352 RadioFans.CN 收音机爱 好者资料库 Elt,seE.argEr We s

2、ound betler. WARRANTY Maranrz Company, lnc-, prosdly warrants your Marnlz prodct io be free o manulacturins defects in material and workmanship as lollows: From date oI Purchase ErectroniccomponenrsadReceives iH: :I:i: +Channd Remote Control Pluq-in Matrix Decode Speake and Cabinets PARTS . 3 vea LA

3、BOR - 3 years PARTS 3 years LABOR - 3 years PARTS - 3 yeals LABOR - 3 yea PARTS - 5 years LABOB - 5 ya TO VALIDATE YOUB WARRANTY, YOU MUST FILL OUT AND IVIAIL THE WABRANTY BEG ISTRATION CARD TO MAFANTZ COMPANY, INC., P. O. BOX 99. SUN VALLEY, CALIFORNIA 91352. WITHIN TEN DAYS FOLLOWING THE DATE OF P

4、URCHASE. For Wannty repair, send this Ploduct to Maran? Companv, lnc., 8150 Vineland Avenue, Sun Vallev, California 91?52, or to an AUTHORIZED Mamnlz Service Station. All shippinq charges must be prepaid, lvlEntz will pay return shipping charges ro anv d6iqnated Point within the United States. This

5、Wrranty is void if the terial nmber has been altered or removed; if the Product is mddilied or repaird in any manner which Marantz believes mav affci the reliabilitv of the product; iI the product k not oprted in aeoldance with the insttuction manual. l/brantz shall have no liability whtsoever lor c

6、onsequentil damages. The sole resPonsibilitv o Marantz Comp.ny, Inc, under this Wairanty shall be limited to the tePair oI the product, or teplacement thereoi in rhe sole diicrerion ot 4arantz company, lnc. EXCEPT TO THE EXTENT THAT APPLICABLE LAW PBECLUDES A DISCLAIMER OF WARRANTY, THERE IS NO III/

7、IPLIED WARRANTY OF IIIERCHANTABILITY OR FITNESS WITH RESPECT TO THIS PRODUCT, NOR ARE THEBE ANY OTHEB WARBANTIES WHICH EXTENT BEYOND THE PROVISIONS OF THIS WABRANTY. 81 50 Vineland. ,$tetue. Sun Valle./, Califltnio 91352 REGISTRATION FOR MARANTZ 3.YEAR GOLDEN WABRANTY lvlodel: Marantz IVlodel 2245 S

8、erlal No- Purchased From Name) ,nitffi piiE#$fl fd$i $ifi fi$iFiII Date Wardnty Replv Cdrd l,4ailed The above information becomes yo!r permanent re.ord ol a valuable purchase. lt shouLd be promptly filied in at the same time that vou fill ln and mai th waiianty reg stratlon reply crd to t,4arantz. T

9、hls information provides a !alabie lnsurnce record and must also be referred 1o should Vou hve any correspondence wirh Maranlz. RadioFans.CN 收音机爱 好者资料库 TABLE OF CONTENTS Preparation for Use Rear Panel Connections Phono Tape ln Tape Out Auxiliary Ouadradial l4ain ln and Pre Out Loundspeaker Systems A

10、nlenna Attenuator Power Connections Connection to AC Outlet Convenience Outlet Simplif ied Operating Procedure Tuning lvleters Tuning l4ono Switch Tape lMonitor Switch Loudness Switch Low Filter Switch Hi Filter Switch l4uting Switch and Level Control lVIain Controls and Switches Selector Switch Bal

11、ance Control Volume Control Bass l4id and Treble Controls lVIain-Spkr Remote Switch Front PanelJacks Dubbing Out Dubbing ln Stereophones Some Suggestion on Using Tape Recorders with Your Model 2245 Recording and Playback Becording Playback lMaaing Two Recordings Sirnultaneously Becording a LongDurat

12、ion Program Copying and Editing Convertinq Your Stereo System to 4 channel Technical Description General Functional Description Front End lF Stages Lim iter FM Stereo Demodulror 2 2 2 2 2 3 3 3 3 4 5 5 5 5 6 6 6 6 6 6 6 6 1 7 7 7 7 7 8 8 8 8 I 8 8 I I 11 11 11 11 12 12 12 l,4uting Circuit Selector S

13、witch Tape Signals Tape l4onitor Switch Phqno Signals I4ono Functions Control Circuits Balance Control Volume Control Tone Ampliier Hi-Lirw Filter Output Stage and Protective Circuits Technical Specificataons Typical Perormance Curve Service Note 12 12 12 13 13 13 14 14 15 15 15 16 17 19 LIST OF ILT

14、USTRATIONS 1. Rear Panel Connection Facilities and 2. 3. 4. 5. 6. 7. 8. 10. 11. 12. 13. 14. 15. 16. 17. Adiustments 2 Loudspeaker System Connectlons 3 Fl4/A4 Antenna Conneclion 4 AIVI Ferrite-rod Antenna 5 Front Panel Controls and Jacks 1 Stereophone Plug I Arrangement oJ Two Tape Becorder I Connect

15、ion Diagram 10 Functional Block Diagram 1l PhonoEqualizationCharacteristics 13 Tone Control Characteristics 14 Low and High Filter Characteristics 14 FlVi Characteristics 17 Stereo Separation 17 Harmonic Di$ortion 18 Frequency Response 18 Pckinq lnstructions 1S RadioFans.CN 收音机爱 好者资料库 F3HWffiMM For

16、optimum performance and enjoyment from Vour l,4odel 2245 Sleteo Receiver, please srudy these instructions carefLllly. lnstallation and opera lion are not complicated, but its flexibility and fpatues deserve yoL/ beLomlrg ldnrllal wlth ils controls and connections. This manual is divided into two par

17、ts The first covers installation and operation in simple, non-technical lanqllage. The second describes the 2245 in mote detail with technical specifications, Junctional explanations, and special application disclssions. For quick identification of the controls and connections, references to them ar

18、e printed in boldface type, exacrly as thev appear on the fronl and rear panels o Your Receiver- ffi ffi ru ffi ffi A- mffi s#ft I rT!f-p$ Your lMarantz Model 2245 all solid state recelver incorporates the advanced circuitry for which l4arantz is famous in the audio component ind!rstry. Unparalleled

19、 technology and innovation made possi ble this combination of three superb component sections on a single chassis: Tuner, Preamplifier, and Power Amplifier. lnternal connections be- tween these cornponent sections ensure optirnum perorrnance from each section, and retain the full flexibility o separ

20、ate components- The extra- ordinary flexibility o your l,4odel 2245 permits the connection of: two srereo pairs of loudspeak ers; headphones; a lurntab e or record changer; an additional luner (such as SW or LW) and TV solrnd source. Record, pLayback, and copying capabilities are included or a lape

21、playback deck or two recorders. AFTER UNPACKING It is advisble to save all original packing material to prevent damage should you wish to transport or ship the Receiver (refer to Figure lT for packing instructionsl. Please inspect your l,4odel 2245 catelully Io( aoY signs of darnage in transit. lt h

22、as undergone stringenl quliry conTrol inspection dnd rests ptiot to packing, and left the actory in perfect operating condition. lf the unit is damaged, notify the carrier without delay. Onlv the consignee may institute a claim with the carrier for damage during shipment. However, the l4arantz Compa

23、ny will cooperate ully in such an Save the damdged carlon as evidence jor inspeclion by the carrier. RadioFans.CN 收音机爱 好者资料库 C PHONO I he phono jdcks are intended lor use with magnetrc phono cartridges requiring a standard 47,000-ohm resistive load. lf hum is heard when playing records, it is usuall

24、y evidence ol improper grounding or shrelding ot the record prayer or its connections. Try reversing the polarity oJ the turntables power plug. lf this is ineffective, connect a separate ground wire from the tLrrntable or record changer frame to the CHASSIS GROUND binding posts of the lModet 2245. t

25、f the tone arm is mounted on a wood panel or is otherwise insulated from the turntable frame, connect the lone arm mounting base to the grounding wire with d short wrrp. ll thc t!1,o pars o signal wires in the arm have a single overall shield, trv grounding lhe shield instedd ol the drrr Figure l. e

26、ar Panel C0nnectiofl FacililiesEnd Ad,ustmeds itself. Keep the two PHONO connecting cables and the grounding wires close togelher to minimire ground loops. TAPE IN The pair o TAPE lN jacks serve two purposes: 1. Wilh the selector slvitch irJTAPEbosition, signals can be played from a tape recorder se

27、t for playback mode of operation. This permits playinq the tape sou rce stere ophonically or monophonically as indicat- ed by position of MONO pushswitch. 2. With the selector switch in any other position, and while your tape recorder is recording, you can monitor the resulting tape quality bv depre

28、ssing the TAPE MONITOB pushswitch. This presumes that your recorder is equipped with separate record and playback heads and separate record and playback electronics. TAPE OUT Connectinq these iacks to the line or tadio inputs of a tape recorder permits recording from the program source indicated by

29、the selector switch. The signals available at this pair of jacks are not affected by the balance. volume, treble, mid, bass, LOW FILTER, Hi FILTER. or LOUDNESS and lvlONO pushswitches on the front panel. PREPARATION FOR USE REAR PANEL CONN ECTIONS All signal connections to the l4odel 2245, wilh the

30、exception of the Fl4 antenna and loudspeakers, $ould be made with shielded audio cables. Figure 1 shows the location of input and output jacks on the rear panel. These jacks are for permanent connections. Front panel jacks and their use will be discussed ldtpr. The rear panel siqndl connections are

31、arranged in slereo pairs. To avoid confusion, connect one cable at a time between the 2245 and the other components of your system. ln this way, you wili avoid cros+connecting channels or con fusinq siqnal sources with destinations.c RadioFans.CN 收音机爱 好者资料库 AUXILIARY High level AUX input iacks are f

32、or miscellaneous sources such as extra tape players with self contained playback preampl if iers, phono cartridges wilh RIAA equalized high-level output, additional t!ners and/or receivers, TV sound outputs, and other external components. OUADBADIAL ln anticipation of rhe coming o 4 channel stereo b

33、roadcastinq, your llodel 2245 is equipped with an ourpur OUADRADIAL jack. The signal available at this jack is the unequalized, buffered output of the Fl,4 discriminator. lts level, frequency response characteristic and output impedance are ideal to drive anv 4 channel adaptor. This jack can also be

34、 used as a simple white noise generator for re quency response check of loudspeakers or ampli fiers, with the lvlodel 2245 in FI4 mode and tuned off from any FM signal. MAIN lN and PRE OUT Connections Jrom the l!4odel 2245 preamplifier outputs to the power amplifier inputs are per +ormed externally.

35、 Special jumper plugs normally interconnect these lvlAlN lN and PRE OUT iacks Removing these two special jumper plugs allows you 10 use vour 2245 as an independent basic stereo amplifier and/or an independent stereo control center, Be sure to replace the iumper plugs between the MAIN lN and PRE OUT

36、jacks for normal operalion. 3 Figure 2. Loudsteaker System Connections LOUDSPEAKEB SYSTEMS The SPEAKEB SYSTEIMS terminals on the rear panel will accommodate Iwo stereo paars of loudspeaker systems of rated impedance between 4 ohms and 16 ohms. When using only one stereo pair o loudspeakers, connect

37、them to the MAIN terminals. The REII4OTE erminals are for a second stereo pair of loudspeakers. Selection of loudspeaker systems is made wilh the lvlAlN-SPKR-REMOTE pushswitches on lhe front panel. Use caution when connecting your lvlodel 2245 to a loudspeaker with bualt in power supply such as an e

38、lectro-static loudspeaker, Tl,e common conneclion terminal of such a speaker may be capacitivelv qrounded through its power supply. Vlake sure the GROUND terminals of the Model 2245 are connected to the common terminals of such loudspeaker system. Ordinarv #18 qauge, 2 conduclor lamp cord (zipcordi

39、may be used for normal distances (to about 25 Jeet) belween your 2245 Receiver and your loudspeakers. For longer lengths, +16 gauge, or heavier wire should be used to ensure optimum speaker performance. When connecting a slereo pair of loudspeakers, it is important to ensure correct relative phasinq

40、 (polarity). When usinq identical loudspeakers, simply code one wire of each pair at both ends with a knot, tape. etc. J RadioFans.CN 收音机爱 好者资料库 C (Note: Close inspection of stndard zipcord will pvaal orp lorr ocodinq o1 lhp r1ulatron,4,q, rioqF o goovp on ono pouo. onp o llF wrrp ny be silver while

41、 the other is bare copper.) Coded wires help insure identical connections for each channel, For each channe. the coded wire can be connecred between the commoi termjnal of your loudspeaker and the GROUND terminal of the amplifier channel. The remaining uncoded wire is then connected between the rema

42、ininq Loudspeaker and amplifier lerminals. This insures correct polarity or phasing o identical loudspeakers. l there is any doubt about phasing o loudspeaker pairs, or if they are not identical loudspeakers, a simple listeninq test can verify correct phasing. With program signals fed to both channe

43、ls, and with the MONO pushswitch depressed, the sound should appear to originale at a point midway between the loudspeakers, with the balance control centered. As the balance contro is turned away from the center position, the sound source shou d appear to move toward one of the Loudspeakers. Room a

44、coustics can somelimes make this test ambiquous or confusing. lf so, lemporari y rnove the loudspeakers as c ose toqether as possible. Then set the controls for balanced IMONO opertion and listen to program material with strong bass pass ages. Reverse the wires to one of the loudspeakers and listen

45、to the same passage again- lf there is .oficobly less bs w l I c Fvp ad , orncr:on. change the connections back to the original ar ranqement. lf there is noticeably more bass, leave the wires connected in reverse, These phasinq procedures should be used with each stereo pair of Loudspeakers, whether

46、 IMAIN or REMOTE. lf both pairs of loudspeakers are used in the sanre listening area, ensLrre that the 4AlN peir is also in phase with the REMOTE pair. CAUTION: NEVER DIRECTLY CONNECT THE LOUD SPEAKER TERIVINALS OF ONE CHANNEL IN PARALLEL WITH THOSE OF ANY OTHER. ANY RESULTING DAMAGE IS NOT COVER ED

47、 UNDE R WARRANTY. FM ANTENNA The best F / reception is obtained with a Log-Periodic type antenna, moLnted on a qood quality rolor system. For fringe ares, I4arantz recommends a Log Periodic antenna with six or more elements designed expresslV Jor FM reception. For minimum local noise and multipath p

48、iclLrp by the lead in wires, Lrse a balanced nd shielded 300ohm cable. (An unshielded lead-in wire can act as n omnidirectional antenna, and can cancel the directional benefits of your 1pr1a.) Lolv los.300.ol_Tl eldd cdbp or,sls of two inner conductors plus an ouler shield and insulating jacket. Thi

49、s type of shielded cabe effectively prevents the lead-in from contributifg multipath distortion. For rural areas, it is recommended that a loca dealer be consulted about antenna installation and lightning arrestor protection- I,4aster antenna system are not recommefded or use with your Model 2245; such systems are usually designed expressly or television reception and frectuently suppress FM siqnals before distribution. ln addition, rnaster antenna systems often severely limit good qLrality FIVI reception. Where ouldoor antennas are prohibited or inconvenient, use a