《PCN_2,_PCN_4_Crossover_Service_Manual 电路图.pdf》由会员分享,可在线阅读,更多相关《PCN_2,_PCN_4_Crossover_Service_Manual 电路图.pdf(7页珍藏版)》请在收音机爱好者资料库上搜索。
1、PCN 2 & PCN 4 ELECTRONIC CROSSOVER NETWORK PCN 2 P/N 071-5510-000 PCN 4 P/N 071-5520-000 SERVICE MANUAL CONTENTS: Notices Specifications Therory of operation Parts lists: Circuit board Chassis assembly Miscellaneous Schematics PCN-2 Service diagram PCN-2 Schmatics PCN-4 Service diagram PCN-4 Fender
2、Musical Instruments Corp. 7975 North Hayden Road Scottsdale, AZ 85258 PCN-2 & PCN-4 (These are the model names for warranty claims) OCTOBER 1995 IMPORTANT NOTICE: The information contained herein is CONFIDENTIAL and PROPRIETARY to Fender Musical Instruments Corp. It is disclosed solely for use by qu
3、alified technicians for purposes of equipment maintenance and service. It is not to be disclosed to others without the expressed permission of Fender Musical Instruments Co. All specifications subject to change without notice. For warranty repair service, only Fender specified part numbers are to be
4、 used. It is recommended they also be used for post-warranty maintenance and repair. Parts marked with an asterick (*) indicate the required use of that specific part. This is necessary for RELIABILITY and SAFETY requirements. DO NOT USE A SUBSTITUTE! A coded naming convention is used in the descrip
5、tion of certain parts. The codes and what they mean are as follows: CAPACITOR CODES HARDWARE CODES CAP AE=Aluminum ElectrolyticBLX=Black Oxide CAP CA=Ceramic AxialCR=Chrome Plated CAP CD=Ceramic DiskHWH=Hex Washer Head CAP MPF=Metalized Polyester FilmM=Machine Screw CAP MY=MylarNI=Nickel Plated CAP
6、PFF=Polyester Film/FoilOHP=Oval Head Phillips PB=Particle Board RESISTOR CODESPHP=Pan Head Phillips PHPS=Pan Head Phillips Sems RES CC=Carbon CompSMA=Sheet Metal A Point RES CF=Carbon FilmSMB=Sheet Metal B Point RES FP=Flame ProofSS=Stainless Steel RES MF=Metal FilmTF=Thread Forming RES WW=Wire Woun
7、dZI=Zinc Plated 1 RadioFans.CN 收音机爱 好者资料库 SPECIFICATIONS Part Number:PCN 2071-5510-000 PCN 4071-5520-000 Crossover Filter Type:4th order state variable Linkwitz-Riley 24 dB/octave slope Input Type:Balanced Differential Input Impedance:20 K Output Type:Floating and Balanced Line Drivers Output Impeda
8、nce:300 Frequency Response:10Hz to 20kHz +/- .5 dB Frequecy Range:Low 80 Hz to 920 Hz High 800 Hz to 9.2 kHz Total Harmonic Distortion:2Kohms) Maximum Output Level:+21 dBu (6.2 volts) 2Kohms) Maximum Voltage Gain:6 dB Constant-Directivity Correction:+3 dB 3.5kHz rising at 6 dB/octave to 22.5kHz Hum
9、and Noise: - 100 dBu Signal To Noise Ratio:108 dB +21 dBu Input Power:20 Watts (all voltages) Dimensions: Height:1-3/4 in. (4.45 cm) Width:19 in. (48.26 cm) Depth:7-1/2 in. (19.05 cm) Weight:8 lbs (3.6 kg) THEORY OF OPERATION The PCN-2 is a professional stereo 2 way electronic crossover network, whi
10、ch may also be used as a mono 3 way unit. The PCN-4 is a professional stereo 3 way electronic crossover network, which may also be used as a mono 4 way unit. Both use a unique and highly accurate 24 dB per octave Linkwitz-Riley filter system. Additionally, the PCN- 2&4 are among only a few units tha
11、t provide a flat summed response of the low and high frequency outputs regardless of the crossover frequency chosen. This is accomplished by using precision 2% resistors, carefully selected capacitors, and the industrys only precision matched hand selected 1% four gang frequency range potentiometers
12、. The input stage (IC101B) will accept a Balanced or Unbalanced signal via an XLR jack with pin # 2 being Hot (Non- inverting). The input stage provides a gain of 1 and High frequency cut-off at about 75 kHz. The input level control (R105) feeds the second stage, using C104 and R110 to provide the s
13、witchable Constant Directivity Horn equalization (CD boost). This feature compensates for the high frequency rolloff inherent in Constant Directivity horns. The boost is +3 dB at 3.5 kHz, rising 6 dB per octave to 22.5 kHz. ICs 102, 103, and 104 make up the Linkwitz-Riley 4th order State Variable fi
14、lter with 24 dB per octave slopes. This filter will produce low pass and high pass transfer functions simultaneously. The precision components allow precise matching of the filter knee points. The PCN-2 changes easily from a stereo 2 way to a mono 3 way mode by engaging the switch (S103) on the rear
15、 panel. In the mono 3 way mode, the high frequencies are available at the High Output on the A channel. The A channel frequency control sets the High crossover point. The remaining Low and Mid frequencies are tapped off IC104 on the A channel. They connect to the B channel at R111 via the mode selec
16、t switch (S103). The output of IC102 pin 1 provides the Mid frequencies to the High Out B output of channel B. The output of IC102 pin 7 sends the Low frequencies to the Low Out B output. The B channel frequency control sets the crossover point between the Low and Mid frequencies. The PCN-4 does not
17、 feature a switch to change from a stereo 3 way to a mono 4 way mode. However, to operate the unit in a mono 4 way mode, connect the High output of channel A to the Input of channel B. Therefore the Lows appear at Low Out Ch A, the Low/Mids appear at Mid Out Ch A, the High/Mids appear at Mid Out Ch
18、B, and the Highs appear at High Out Ch B. After the filter section, the signals feed the Mute Switches (PCN-4 only), level controls, buffer amps, Phase Reverse switches (PCN-4 only), and to the output circuits. The output circuits are Balanced low impedance line drivers, ideally suited for driving l
19、ong cable runs. The outputs will function properly in an unbalanced mode by grounding pin 3 of the XLR jack. However, doing so will compromise the common mode rejection capability of balanced circuits. Located just prior to the output XLR jacks are a pair of JFets. One JFet connects from pin 2 to gr
20、ound. The other connects from pin 3 to ground. They mute the outputs for about 3 seconds after power-up. This prevents turn-on transients from reaching the power amplifiers during a power interruption. Upon power-up, C159 charges through R181 providing the delayed signal output. When you switch the
21、power off, C159 discharges immediately through D101, muting the outputs. The power supply uses adjustable regulators set up to deliver +/- 16.5 Vdc. 2 RadioFans.CN 收音机爱 好者资料库 PARTS LIST PRINTED CIRCUIT BOARD ASSEMBLY QTY PART # DESCRIPTION REFERENCE DESIGNATION 1028460CAP AE RDL4.7F50VC159 028474CAP
22、 AE RDL100F25VC103,114,115,118-121,134,135,138, 139,140,141,160,161,165,197,198, 199,214,215, 218-221, 260,265, 503-506 2028494CAP AE RDL1000F35VC501,502 007029CAP CD220PF50V5%C101,102,116,117,136,137,216,217 049351CAP CD.1F25VC150-157,252,253 030935CAP PFF RDL .0018F50V5%C106,108,110,112,122,123,14
23、2,143, 222,223 030944CAP PFF RDL .0082F50V5%C104 030947CAP PFF RDL.015F50V5%C105,107,109,111,206,208,210,212 049352CONTROL 10K PC MT RT ANGR105,131,161,205,231,261(LEVEL) 1 = SET OF 4 049353CONTROL 50K PC MT RT ANGR123-126,223-226 THE FREQUENCY CONTROL USES 4 POTS GANGED TOGETHER AND MATCHED WITHIN
24、1%. THEY MUST BE REPLACED AS A SET 39902204580DIODE 1N4148 SIGNALD101,503,504 6049354DIODE IN4001 50PIVD501,502,506-509 049355IC DUAL OPAMP JRC NJM2068DIC101-113 19902203170IC REGULATOR POS ADJUST LM317T 1049356IC REGULATOR NEG ADJUST LM337T 031935JACK XLR MALE RT ANG PCB 029177JACK XLR FM RT ANG PC
25、B 1025792LED GREEN 2MMX5MM DIFFUSEDD505 049357RES MF1/4W1501%R147,148,177,178,247,248 049358RES MF1/4W2001%R503,504 016946RES MF1/4W8251%R110, 025810RES MF1/4W2.49K1%R116,216,501,502,507,508 049359RES MF1/4W3.57K1%R115,117,215,217 049360RES MF1/4W4.99K1%R132,160,232 015582RES MF1/4W10K1%R119-122,127
26、-130,219-222,227-230, 031940RES NET 10K 4 ISOL ELEM SIP2%R101-104,106-109,111-114,119-122, 127-130,139-142,143-146,169-172, 173-176,201-204,206-209,211-214, 239-242, 243-246,269-272,273-276 049361RES MF1/4W15.4K1%R118,218 016969RES MF1/4W27.4K1% 015585RES MF1/4W100K1%R149,150,179,180,249,250 040744R
27、ES CF1/4W1M1%R181 PARTS LIST PRINTED CIRCUIT BOARD ASSEMBLY CONTINUED QTY PART # DESCRIPTION REFERENCE DESIGNATION 1028091SWITCH PUSH SLFLK SHORT STROKES102,103,104,105,106,107,202 (MUTE, PHASE REVERSE, CD BOOST) 2049362SWITCH DP4T PUSH RT ANG PC MTS101,201(X10 SWITCH PCN2 ONLY) 1049363SWITCH POWER
28、DPDT PC MT PUSHS501(120V BLUE PWR SWITCH) 1049592SWITCH POWER DPDT EXPORT IECS501(230V GREEN) 1049364XFMR PC MT 40V 300mA 115/230VT501 014689XSTR N-CH JFET J111 TO-92T101-106,201-204 CHASSIS ASSEMBLY QTY PART # DESCRIPTION REFERENCE DESIGNATION 1036702FUSEHOLDER 3AG FINGER GRIP(120V DOMESTIC ONLY) 1
29、036703FUSEHOLDER 5X20MM FINGER GRIP(230V EXPORT ONLY) 1049365FUSE QA 1-1/4X1/4 250V 250mA(120V DOMESTIC ONLY) 1049593FUSE QA 20MMX5MM 250V 125mA(230V EXPORT ONLY) 049366KNOB SQ. PUSH BUTTON GREY PCN 049367KNOB RED W/SQ. SHAFT PCN2,4 049368KNOB GREY W/SQ. SHAFT PCN2,4 1049369SECURITY COVER PLASTIC SMOKE MISCELLANEOUS QTY PART # DESCRIPTION REFERENCE DESIGNATION 1048905SCHEMATIC REDU W/SVC DIA PCN2 1048906SCHEMATIC REDU W/SVC DIA PCN4 3 RadioFans.CN 收音机爱 好者资料库