www.SteamPoweredRadio.Com
Page 1: ...www SteamPoweredRadio Com f 35i d half track f ll track an series 351 u d cer I epro u h m e recorder r ck stereop o 35 1 2twot a series d cer der repro u recor TM 2002...
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Page 3: ...www SteamPoweredRadio Com mo el 5 recorder reproducer UJ al 0 1 u 0...
Page 4: ...N OUTPUT INPUT SUMMARY PlJONES REMOTE CONTROL 60 CYCLE AMPLIFIER OVER ALL P HFORMANCE CIIECK DISTORTL ON FLUTTER AND WOW OPERATION GENERAL SUMMA HY OF CONTHOLS SWITCHES AND INDICATORS OPERATING TECll...
Page 5: ...LECTHONIC ASSE IBLY GENl HAL RECOl l MIPLJrlEH REPRODUCE A lPLIFILH BIAS N I HASE OSCILI AfOB POWEil SUPPL Al IC N 11 T AND Pl lffOH lANCI Clll CKS STANl HI TAPl S on s O I ALll I Tl Hl OPIIOI IC I QU...
Page 6: ...RACK lNTERCONNECTTNG TAPE TIIHEAOING PATH VALDEMAR POULSEN MAGNETIZATION UF TAPE RECORD IIEAD RECORDING MEDIUM MAGNETIZATION CURVE REPRODUC8 II EAD CIIARACTERSTJCS ACII IEVING FLAT OVER ALL RESPONSE C...
Page 7: ...C SUBASSEMBUES AMPLIFIER CHASSIS FRONT PANEL AI IPLIFIER CJIASSTS REAR VIEW BLOCK DIAGRAM RECORD CIRCU IT BLOCK DIAGRAM REPRODUCE CIRCUIT IIEAD AZIMUTII ADJUSTI VIENT SIGNAL TO NOISE RATIO COMPUTATION...
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Page 9: ...for use with the inch magnetic tape and an electronic assembly which contains the record amplifier reproduce arnpUfier bias and erase oscillator and power supply all featuring etched board construcUon...
Page 10: ...s Peak recotd level is that level at which the overall input to output total rms harmonic distortion does not exceed 3 percent when measured on a 400 cycle tone Noise is measured when erasing a signal...
Page 11: ...kes possible selection of the proper tape tensioning for the NAB 10 inch diameter reel or the EIA 5 inch and 7 1nch reels The INPUT TRANSFER SWITCH provides a means for selecting three different types...
Page 12: ...fier is used with the equipment power requirements are greater by 2 5 amperes single track equipment 4 5 amperes dual track 5 0 amperes EQUIPMENT AVAILABLE Item Height Depth Wicll h Tape Transport 15...
Page 13: ...necting dia grams at the back of this section MOUNTING Console Models To assemble the console m odel proceed as follows Step 1 JnstaJl the tape transport in the cab 1net frame securing the 8 oval head...
Page 14: ...in a ready to operate conclition except for the connection of interconnecting cables Conven ient rubber feet arc located at both ends of each case and metal rests arc provided on the 2 2 backs of each...
Page 15: ...g for 4VU output 2 3 To obtain a center tap grounded balanced output strap the black lead of transformer T3 to ground at the tie point shown in the illustra tion Plus 4 v u output can be achieved by u...
Page 16: ...sformer socket Step 5 Wire the microphone mput connector for connection to pins 1 and 2 shield to pin 1 and leave pin 3 open Bridging a Balanced Studio line Connect a balanced line to pins 2 and 3 of...
Page 17: ...5763 03 units are mounted on a flat plate for installation in studio consoles and are not wired For Model 351 2 use 5763 02 in the wooden case or 5763 03 mounted on the flat plate To install wire as...
Page 18: ...inch speed The Ampex Professional Products Division primary standard of measurements is based on the use of a flutter meter calibrated to indicate the deviation from mean carrier frequency of any rat...
Page 19: ...ONIC ASSEMBLY I I I I I I I I I 11 I I 11 11 11 I I 11 11 I I I I I I I I 1 1 I I I I I I 1 1 I I I I I I note 3 I I I r _____ ___ l l f 0 1 1 s r r61101 0 i g l6J i e o 0 l I I S 4 bias C13 IOI I 0 l...
Page 20: ...www SteamPoweredRadio Com Model 351 Console 2 8...
Page 21: ...ter tape reels or the E IA 5 and 7 inch reels Provision is made for selec tion of proper tape tensioning at the REEL SIZE switch on the tape transport for the LARGE or SMALL size reels NOTE In the LAR...
Page 22: ...if tape is properly threaded or the safety swHch is mechanically closed_ The v u meter L amps light when power is on and are unaffected by the safety switch remaining lighted till the power is turned...
Page 23: ...lifier In the ON posWon a 560 ohm resistor is across the output ln the OFF position the resistor is out of the circuit and the amplifier must then feed a 600 ohm device Controls tape motion in the rep...
Page 24: ...ST FWD STOP and PLAY PLAY OR RECORD The tape is set into play motion at the speed selected by the tape speed switch when the PLAY button S505 is pressed To change from play to lhc record mode with the...
Page 25: ...rase 3 5 current The erase current is not critical and has been factory adjusted to read approxi mately on the vu meter for half track and stereophonic heads and I for full track heads Both the erase...
Page 26: ...a conversation cou1d be permanently recorded for reproduction at any time In the early 1900 s many scientists were attempting to use magnetic tape in preference to the earlier idea of wire About 1927...
Page 27: ...orce is alternating and the iron oxide particles arc aligned ac cording to the instantaneous direction and mag nitude of the field TAPE s N s FLUX s N tt t N s SIGNAL 1 e Magnetization of Tape The mag...
Page 28: ...ead be as small as possible so it will intercept less than one wave length of the signal on the tape at the highest frequen cy to be reproduced However as tbc gap is made smaller the in duced voltage...
Page 29: ...il This induced volta e is attained as the flux travels through each branch of the head core forced into that path by the high reluctance of the head gap There fore an instantanrous difference in the...
Page 30: ...low freguency limit is determined by how far this decrcasjng output can be tolerated while maintaing an adequate 4 5 signal to noise ratio Thus the noise generated by the associated electronic assemb...
Page 31: ...as the operator faces the equip ment tape is delivered to the take up reel when the PLAY or FAST FOHW RD buttons arc pressed tape is rewound onto the supply reel when the REWIND button is pressed Prop...
Page 32: ...turntable will rotate clockwise and the tape take up turn table counterclockwise Motor torque in the reproduce and record 5 2 modes is adjusted to equality by the tensioning adjustment resistors R503...
Page 33: ...E EXERTING AN OPPOSING FORCE TO THE TURNTABLE ROTATION 1 0 t 0 TAPE MOTI ON FAST FORWARD TAPE MOTlON REWIND TAPE MOTION RECORD OR REPRODUCE Tape tensioning 5 3 TAKEUP TAKEUP _ I I I I I I r I I I I 5...
Page 34: ...the wpc drive sy tf m is to transport the tape across the hc ids al a uni form speed during the record and rc proclucc processes By means of a hysteresis synchron 5 4 ous capstan drive motor B501 and...
Page 35: ...Control Circuits Located in the control circuit box under neath the tape transport are all relays the ten sion adjustment resistors and electronic com ponents such as the capacitors and resistors show...
Page 36: ...torque and tape is pulled a t a maximum speed from 5 6 the take up to the rewind reel Contact set K504 3 completes the d c circuit to the brake solenoids at each reel assembly thus releasing the brake...
Page 37: ...posil ion ot 1 reels 11111st be EIA NOTE Tile Catalog Number 5700 tape tra11 1 purls wwd 011 carliu IH lc els chmzgcd PLAY tem iun only whe11 i11 tlzc SMALL reel position 5 7 ROUTINE MAINTENANCE Care...
Page 38: ...hole whjch wilJ be on the top or the side of the motor end belJ Place not more than four drops of a recommended lubricant in the oil hole OC 11 5 8 CAUTION Do 110 ovcr l11brica L Wipe otr CJ CC 8 oil...
Page 39: ...amplifiers with abnormally high input signals Such signals would be 10 db greater than tape saturation or approximately 30 db greater than normal opernting level If it becomes necessary to test the he...
Page 40: ...d take up motors must be adjusted to between 6 and 7J 2 ounces as read on the 16 oz spring scale at NAB reel hub diameter Checking techniques are not difficult and should be performed carefully Step 1...
Page 41: ...le will rotate clockwise Repeat the entire process on the take up turntable SPRING SCALE READING Direction of Most Resistanee Supply Connterclockwise Taheup Clockwise 15 to 16 ounces Direction of Leas...
Page 42: ...ves tbe capstan The scale reading should be 5 lbs lb If necessary adjust the capstan dig at the point shown in the illustration Replacement of Parts All sub assemblies of the tape transport me chanism...
Page 43: ...nd of the brake band next to the solenoid Step 8 The brake band may now be removed taking caution not to lose the band leaf on the solenoid side There is only one band leaf per assembly 5 13 Step 9 Po...
Page 44: ...J 1 I look thr lmike pl ing to tlw brake lc nT Step 3 1q1 1 lkpl tcc tltc lllOlOJ a rrnhil ti ht n ing the f our nut and 1dcli11g t tc washer that II l l l 1110 1 c d in Step I Pt CKJNC Pf F C UT ONS...
Page 45: ...rt Eye Bolt Crosshead Anchor Spacer Roll Pit J 8 inch x 3 4 inch Screw Socket head cpa st cad pl Brake Band Link Brake Band Clamp Brake Lever Odvelock Pin l 8 i nch x l 2 inch Cotter l 16 inch x 1 2 i...
Page 46: ...r 3 3 4 7 l 2 ips machine Individu 1lly replaceable parts Felt Washer Retaining Ring CAPSTAN IDLER SOLENOID ASSEMBLY lnd ividually replaceable parts Capstan solenoid Capstan solenoid eye bolt Capstan...
Page 47: ...tubular axial leads 0l uf 20 400 vdcw Astron Part No ML 4 01 Same as C507 Same as C503 Same as C503 Same as C50 3 CONNECTOR receptacle female 21 contacts chassis mounted Jones Part No S 321 AB CONNECT...
Page 48: ...SO RESISTOR adjustable wirewound 150 ohm So o 50 watts Tru Ohm Part No AR 50 RESISTOR adjustable whewound 750 ohm So 50 watts Tru Ohm Part No AR 50 Same as R503 RESISTOR fixed composition 100 ohm 10...
Page 49: ...L P507P I TAKE UP MOTOR B502 C512 REWIND MOTOR B50 3 C513 C511 A C CONTROL CIRCUIT 1I5V AC FROM ELECTRONICS ASSEMBLY P507P 2 SR50I SAFETY SWITCH S50I R501 K503 3 K504 I _j_ REWIND S507 1 FAST FWD S5 0...
Page 50: ...REWIND RELAY CABLE TO C502 K502 C K 503 r 3 _ K 504 q_ I 1 E RONIC ggy t t x 3 9 I c q 1 1 f I 2 y CAP MOT 8 c 3 7 c 4 rr I 05 I 100 05 100 I I SAFE SW 7 C 508 fJ H 1 t t t 1 o__ Recoao 6 R504 I 1 N...
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Page 52: ...theory a tape recorder head assembly is a simple device In practice however building a head assembly is a complicated task requiring extremely precise manufacturing techniques There arc three head st...
Page 53: ...compromise The superb design engineering and manu facturing care built into Ampex head assem blies assures dependable long life and econo mical operation at the lowest cost per operating hours A porti...
Page 54: ...gate m the FAST FORWARD and RE VIND modes If a deposit is left it may be removed by xylene on a soft cloth or tissue Never use metal of any kind to touch the head surfaces The gates should never be a...
Page 55: ...ACK ALL UTILIZE THE SAME CONFIGURATIO N Standard 351 l1ead configurations utilizing inch magnetic tape see chart for information on head configuration and Ampex Catalog Numbers INDIVIDUAL REPLACEABLE...
Page 56: ...ched board entity which can be taken from the main assembly by disconnecting the edge on harness connec tors and removing 4 mounting sleeve nuts On the face panel facilities are available for setting...
Page 57: ...subasscrnblies POWER SUPPLY POWER XFMR On the back of the electronic assembly chassis arc all connecting and interconnecting provisions for power input line input line out put power to the tape transp...
Page 58: ...h resistors 4R2 and 4R3 providing the balance above ground From the seconda ry o f tran s former 6Tl the signal then appears a t the grid of 1 1 Using the unbalanced bridge arra ngem e nt transformer...
Page 59: ...ON position For plate voltage to be applied to tl1c ftn d stage the equipment must be in thr record mock al whic h time relay contacts 3 KJC comple te the necessary c ircuitry 7 4 REPRODUCE AMPLIFIER...
Page 60: ...nt adjust ments take place The bias signal is then mixed 7 5 with the record signal and delivered to the record head NOISE BALANCE control potentiometer 1R63 in the oscillator grid circuits is adjuste...
Page 61: ...per second ips 15 inches per second NAB 15 inches per second AME NIImh r Ampex Catalog 3 1331 01 31321 01 31311 01 31312 01 A c Vacuum Tube Voltmeter capable of indi cating rms voltages of 004 or less...
Page 62: ...nt possible if inexperienced personnel without proper equipment have attempted alignment proced ures minor peahs may be observed 7 7 on both sides of the 1naxirn111n The 7noper setting is 15 to 20 db...
Page 63: ...011 y 1111 u111plificr in t 1c r c11rd 11 ode at I Iii I ul c rcw i11u 1111 f n 1 lj17 i l 1 11111pli icr are 11 It 1 1 cu1 1i 11 u le 7 8 Step 6 Using a small screwdriver set the EHASE ADJUST trimmer...
Page 64: ...e the METER and OUTPUT SWITCH in the PLAYBACK position Step 5 Set the audio oscillator to 7500 cps for 3 ips 15 kc for 7 and 15 ips Step 6 With the nut driver rotate the adjust ment nut on the left si...
Page 65: ...1i I i 1 1111 JU CO U IJ Vl t C1 l I JH1 f Ol If tolt r tnu s m not llll I Irnuhl o lwot in1 is i11dirntl d or till l qw c 111 IJf f l llll Overa ll Frequency Response Using the VU Meter SIC I Thn ad...
Page 66: ...value lo Lhc 3 dis tortion level arriving al a tota l of 10 dbrn E xampk 10 clbm 4 6 46 dlim vtvni rmding 5G db signal lo noisr ratio Ampex signal to noise ratio specificaL i ms on a udio instruments...
Page 67: ...tions in this section proceed in this sequence 1 Center the noise balance slot parallel to plane of the chassis face panel if it is not within 45 of center position 2 Set the ERASE ADJUST trimmer for...
Page 68: ...AGE voltage to note aging ol GCRJ 3HG0 ma Ix reduced in alue or shorted out as rcctifil r agl C lean the reby contacts bv inserting t pit cc of high quality bond paper between c ontacts and pulling it...
Page 69: ...17 CMS ct Htt 1 1E t n LUO AUDIO OS GlLl 1 10ft 1 _ lt U CCf ONIC 4 1 Urtlt ll A it it 111118lT Truuble shooting the 1 ecord amplifier Precautions Be careful when removing components from the board to...
Page 70: ...oldering iron to the connections brush away the melted solder Step 4 Insert replacement component and solder the connections Replacing of Tube Sockets Step 1 With soldering iron heat each con tion and...
Page 71: ...co Part No 309 CAPACITOR tubular paper 0 20 uf So o 400 vdcw Sprague Part No 89P20354 Same as 1C3 CAPACITOR fixed paper 47 uf 20 400 vdcw Cornell Dubilier Part No BC4P47 20o 0 CAPACITOR variable mica...
Page 72: ...mica 00091 uf So o 500 vdcw Cornell Dubilier Part No 5AST91 Same as 5C32 CAPACITOR fixed mica 001 uf So a 500 vclcw Cornell Dubilier Part N o SAT535 C APACITOR fixed ce ramie 01 uf 500 vdcw Erie Parl...
Page 73: ...NECTOR receptacle female 6 contact Jones Part No S 306 AB master only CONNECTOR receptacle male 6 cont act Jones ParL No P 306 AB slave only CONNECTOR receptacle male 2 contact Hubbel Part No 7466 mas...
Page 74: ...1 JA RCZ0GF273K 1Rl4 RESISTOR fixed composition 33 meg watt MIL R 1 lA RCZ0GF334K lR15 Same as IRS lRl 6 RESISTOR fixed carbon 1500 ohms i watt MTL R llA RC20GF152K 1Rl7 Same as 1R11 l Rl 8 RESISTOR f...
Page 75: ...e UPE 70 Spec 31186 RESISTOR fixed carbon 39K ohms watt I 0o o MIL R 11 A RC20GF393K Same as Z R29 RESISTOR fixed carbon 22 meg watt l0o o MlL R 1l A RC20GF224 K Same as IR13 RESISTOR variable carbon...
Page 76: ...K RESISTOR fixed carbon 1 5K ohm 2 watts lOo o MIL R 1 lA RC42GFI 52K RESISTOR fixed wirewound 1 5 olim I watt l0o o International Resistance Corp Type BW 1 Same as 1Rll Same as 1R61 RESISTOR variable...
Page 77: ...on 6X4 BOARD ASSEMBLY power supply BOARD ASSEMBLY reproduce 7 15 ips BOARD ASSEMBLY reproduce 3 7 ips BOARD ASSEMBLY record 7 15 ips BOARD ASSEMBLY record 3 7 ips FACING PANEL HARNESS ASSEMBLY master...
Page 78: ...EDfTI NG KNOB console rnd portable HOLD DOWN KNOB r eel for rack REMOJ E CONTROL llNf T single track complete with 30 foot cable Remote Control Unit Parts T701 P CONNECTOR receptacle mal 10 contact J...
Page 79: ...START S7 05 Same as S701 RECORD single track S705 Same as S701 RECORD dual track REMOTE CONTROL UNIT dual track complete with 30 fo1Jt cable REMOTE CONTROL PANEL single track unwired less cabl e and...
Page 80: ...J 2 15 ips Full Track 60 Cycle Power 2 Case Portable 7 1 2 15 ips Full Track 50 Cyc e Power 2 Case Portable 7 l l 5 ips Hair Track 60 Cycle Power Case Portable 7 1 l5 ips Half Track 50 Power 2 Case P...
Page 81: ...00 vdcw 035 l06 Cornell Dublier Parl No BC4P47 20o o Same as C 0047 Used in 7 1 Z 15 i ps Equipment CAPACITOR fixed paper 0082 uf 5o o ZOO vdcw 035 030 Cornell Dublier Part No 109P Used in 3 3 4 7 1 2...
Page 82: ...slow blow Little use Part No 313 500 SF2 FUSE 3 amp 250 volt fast blow Littl t fuse Part No 111 5J 1 SJ 2 5J3 5J4 SJ5 4 J 6 5J7 SJ SJ 8 5 J9 SJl0 3KI 3 12003 Master orJl y POST LIGHT 1 4 watt neon wi...
Page 83: ...1 l watt MIL R 1 lA RC 20GF 334K l Rl 5 Same as R8 lRl 6 RESISTOR fix ed com position 1500 ohm J Z watt MJ L R J IA RC20GFl52K l R17 RESISTOR fixed c arbon ZlK oh m I Z watt 5 MIL R llA RC l 0GFl Z J...
Page 84: ...ohm I 2 watt 0o o MIL R JI A RC 2 0GF5 6 JK Same as R 32 RESIST OR fixed carbon 1 5K ohm l 2 watt 10 MIL R 1 lA RCZ0G F152K RESISTOR fixed carbon 4 7K ohm I l watt 10 MlL R 1 lA RCl0GF472 J RESISTOR f...
Page 85: ...LY reproduce 3 3 4 7 1 2 ips BOARD ASSEMBLY reproduce 7 I 2 I5 ips FACING PANEL HARNESS ASSEMBLY master HARNESS ASSEMBLY slave KNOB large ski rted R eproduce and Record Level Control KNOB small skjrt...
Page 86: ...tt d I hit r K ll O 1 1101 1 11111 l 111111l 1bl f I I I r r r _r j t rl JI p 1ttrWt1i i 1 I I I I I I I I I I I l t r J r r fl r H l tt I I f I I I 1 I II I t Ii 1 11 I I 1 1 I I I i I1It I I 1 i t I...
Page 87: ...LIES ONLY 3Cl6C____ 3C2B _ _____ 4000 MFD 2 i i d s R54f Rf s 1 5 MFO C 350V l if C29 if T Vv 3cIsA l R57 15MFO TC27 C30 350V C26 Nv 6T4 R Y R56 GN0 REC0RD BK 2 I 6T4_ R 3 7 6T4_ Y 4 5 6 6 T4 _ Y 6 T4...
Page 88: ...P OL AS nt RlllEO IN SECTION vor J JITTENANCE MANUAL O C Ol T A M t A SURtO W1Tfl 20 00QOH M Ptft VOi r M r Tt H WJIII t Qlll JlM ITT lN lffCORO MOOE AT lllV UNr JGNAI VOLTAlolS MEASURED Wl TH AC vrv...
Page 89: ...FOR 8 vu OUTPUT ron vu OUTPUT JUMP E TO r IN TEAO Of E TO D ON 6 T l rsn INSl ALLATIOM READJU r r R cono CAU0RATION CONTROL AS ot SCIUBEO IN Sr CTION V OF MAll 7ENAN E MANUAL 6 0 C VOLTAGES Mt ASUHt D...
Page 90: ...IN db R n 1mEO TO 78 VOLl j CIRCUIT CONDITIONS QUAIJZAT10N WITCH 1 12 IN l 1 2 PO fTION 500 C YCl F INPUT l EVl L CONTftOLS H9 AND 4R36 ruu CLOC KWTSE UNE OUTPUT 5JS TEH MlNATEO rN NOMIJ ICAL 600 OHM...
