Ampex-201-Operation-Maintenance-Manual 电路图 维修手册.pdf

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1、COMlANY DElT TO: MODEL 201 CONVERSION Model 201 Conversion Kit consists of the following: Head Assembly MP-475-J Playback Amplifier MP-667 Record Amplifier MP-666 Power Supply MP-656 The kits are shipped in sets. If these sets are not broken, no electronics adjustment will be necessary. If these set

2、s are broken, minor level adjustments may be necessary as well as Bias and Noise Balance adjustment on record. Great care has been taken to maintain maxim:un possible uniformity in all components. INSTALLATION: Remove Record Chassis, Playback Chassis, and Power Supply Chassis from Model 2 00 Recorde

3、r. Remove playback cable from top plate by removing the two Allen-head screws. Remove old Head Assembly. Remove. Gutter Pad. Install new Playback Cable assembly with Allen-head screws used to hold the old cable in place on the top plate. A.plastic clip has been included with the cable assembly and s

4、hould be used to fasten the center of the cable to the center of the shelf in the cabinet. This is to prevent the cable from coming into close proximity with the drive motor, and thereb7 prevents the injection of hum into the playback system from same. Next, plug in the new head assembly and bolt in

5、 place with the two 1/4 inch Allen flat head bolts supplied. Plug in new power supply and amplifiers. Plug erase, record, and playback cables in same. Make sure that record and erase cables have not been interchanged. Plug in strapped plug in place of 10 or 16 Db. pad in gutter. OPERATION: The recor

6、d Level control has been set to effect proper record level on MMM 111 tape when the machine is bridging at 4 vu Program Bus. The playback level is adjusted to play a tape so recorded at a level of + 4 VU into a 600 ohm terminated line. Both input and output lines may be either balanced or unbalanced

7、. It is assumed that the machine has a strapped plug in tbe gutter. ( Q)db. atttenuation) ELECTRONICS ALIGNMENT The machine is normally adjusted for MMM lll tape. Plack lifier. Two controls are provided on the playback amplifier . TEese areT l5 inch High Frequency Equalizer and the Playback Level Co

8、ntrol. The first is used 1ri conjunction with the new 15 inch standard tape. The level control can be adjusted for output levels up to plus 10 vu. The amplifiEr will deliver plus JO dbm. with less than one per . cent harroonic distortion. A special equalization switch position has been incorporated

9、to allow playback of old Model 200 tapes. The playback head is critically damped within the head assem- bly and no further adjustment is necessary at JO inch speed. The output level is adjusted such that standard tape level is 10 db. below program. II. Record AmI?lifier - Erase and Bias Supply. 1. E

10、rase Adjustment. Plug an A.C. VTVM (such as Hewlett Packard 400) into erase current phone jack. Adjust erase current by means of the high frequency amplifier control located in back of the 61.I, tubes. The meter must read 2 . ) to 2.5 volts RMS which is equivalent to 230 to 250 Ma. erase current. (D

11、o not set at maximum.) Adjust head trimner for maxilllun cur rent. Readjust the high frequency amplifier control if necessary. a. Bias Adjwstment. Move meter. plug to bias - record urrent jack. Ad- Just b!as con-Ero! for .52 volts RMS (equiv. to 5.2 Ma. bias cvrent). Note: This adjustment is approxi

12、mate and preliminary only - Connect audio frequency generator to input of nachine. Set machine into operation in the record position. Set generator at 1000 cycles and adjust record level control so that standard tape level (10 db. below program) is effected on playback. Re-adjust bias for naxinllln

13、out-tW/. put !I. 111.a, t!-:., . ,. I I sJ. ;,J I 11. 1. t. sGk I. A,f. Jfp e .f SHt r P 11 . -7 0-N 3. Hi Freuenct Egualizer Adjustment. Re100ve one ot the 6CS tubes lo- cated n bac ofhe6t6 tubes. This will disable the oscillator and al- low the record current to be read on the meter as set up unde

14、r Bias Ad- justment. Set meter to .03 volt scale. Yfith the generator as oonnected before, set high frequency equalizer controls for curves as shown on curve sheets. Replace 6c$ tube in socket. Re100ve meter plug. 4. Record Level A.dgustment. With generator connected as before, set gen- erator outpu

15、t for l db. below program bus level at 400 cycles. Set mach- ine into operation in the record position and adjust record level control to effect standard tape level on playback. Reve generator. $. Noise Balance Adjusl!nt. Short input terminals. Set machine into operation in the reoordpos!tion. Adjus

16、t contro.l slowly for Jllin1111lm noise on playback. This concludes the record amplifier adjustment. THE ELECTlUCAL PERFORMANCE SPECIFICATIONS OF AMPEX IDDEL 201 RECORDER Designed to be used on any tape -factory adjusted for M.M.M. lll tape. Noise at least 60 db. below 2% total harm:nic distortion m

17、easured at 400 cycles per second on 1ll tape. Frequency response: 3011/,c. 1 db. 50 to 15,000 cycles 15/sec. t 2 db. 50 to 15 ,ooo cycles . - Input: bridging or matching, balanced or unbalanced line, normally set for+ 4 V.U. Can be adjusted for any level above -15 v.u. output: normally set for t 4 v

18、.u. Amplifier will deliver +. 28 d.b.m. at L% intermodulation distortion. Features: 1. Smooth, stable frequency response. 15 curve same as AMPEX M:del 300. For playback of other machines see curves attached. 2. Amplifiers set up on easy-to-achieve response curves. 3. Heads held to narrow tolerance t

19、o achieve complete interchangeability of head assemblies and amplifiers. 4. E.xtrenely low under-signal noise due to new type of head housing with mininnun friction on tape. 5. Narrow tolerance guides for uniform tape alignment which assures uniform high frequency output. 6. Hum: Virtually eliminate

20、d by D. C. heaters through- out and multiple alloy shields on heads. 7. Facilities for addition of accessory Meter Control Panel provides metering H.F. Bias Current, Erase Current, Record Current, Record Level, and Output Level. Step controls for controlling Record Level, and Line Level Output. 8 .F

21、hone jack output for Record Current, Bias, and Erase Current provides for ready netering of these currents. 9. Heads placed on same side of tape as AMPEX Model 300 to agree with standard adopted by NAB. - Page 2 - 10. Complete voltage-regulated power supply assures uniform amplification and stable B

22、ias and Erase oscillator regardless of cges in line voltage. 11. Push-pull oscillator driving push-push class A amplifier for extremely quiet Bias and Erase supply that is uncritical to adjustments. HEAD HOUSING The head housing, see Fig. 5, is a die cast assembly which contains the three heads used

23、 in the recording process. The heads are respectively erase, record a.nd playback as viewed from left to right when facing the machine. The gate on the housing holds the playback and record shield covers and the tape-lifting fingers. The function of the tape-lifting fingers is to remove the tape fro

24、m the heads when the gate is open during Rewind or Fast Forward operation. This reduces head wear con- siderably. The tape may leave a deposit on the heads if allowed to contact them at high speeds. Such a deposit will seriously impair the performance of the machine and should be guarded against by

25、al- ways opening the gate on Fast Forward and Rewind. If a deposit is left, it may be easily removed with carbon tetrachloride on a soft rag. Never use metal of any kind to touch the head surfaces. SECTION IV PAGE 1 6-15-49 HEAD ALIGNMENT Remove the top cover from the head housing by removing the tw

26、o screws from the top of same, and pulling cover gently back and up. Looking at the head housing from the front, the three heads from left to right are: erase, record and playback. The azimuth angle of the erase head requires no adjustment, and should not be touched. The record and playback heads sh

27、ould be aligned only after reading and fully understanding the procedure under ELECTRONICS ALIGNMENT. The actual physical alignment of the record and playback heads consists of placing a spintite socket wrench on the left hand elastic stop nut in each head and adjusting back and forth until the prop

28、er azimuth angle is arrived at. This is accomplished by first playing the standard tape and adjust- ing the playback head until maximum response is obtained on the 15,000 cycle tone. The record head is then aligned with the playback head by recording 15,000 cycles on a blank tape, and adjusting the

29、record head for maximum playback output. SECTION IV PAGE 2 6-15-49 HEAD DEMAGNETIZATION Occasionally the heads become magnetized through some electrical fault which may occur in the amplifiers or by coming into physical contact with a magnetized object. In order to demagnetize these heads completely

30、 in such events, a demagnetizer should be used. A demagnetizer suitable for this purpose is manufactured by AMPEX as an accessory item. In the event, however, that time does not permit the owner of the machine to wait for delivery of a demagn_etizer, he may make one as follows: Cut a piece of transf

31、ormer lamination to a x 2 size. Wrap the strip of metal with suitable: insulat- ing material and wind approximately 400 turns of No. 36 wire and attach a 4 length of 2 connector cord. Bend the iron strip into a U shape and bring the ends of the U to a spacing of . Connect to a 6 volt source of A.C.,

32、 open the gate on the head housing and bring the ends of the U in contact with the 2 poles on the magnetized head. Remove the demagnetizer very slowly, allowing the A.C. field to die off gradually. Repeat this operation on record and playback heads only, as the erase head will de- magnetize itself.

33、In the event demagnetization is not effected, repeat the process more carefully. The capstan may become magnetized by contact with a magnetized tool. Should this occur it may be demagnetized with an A.C. solenoid placed over the shaft and slowly pulled away. SECTION IV PAGE 3 6-1H9 +20 15 10 0 0 0 -

34、2 2 20 -+ 8 . . I -,. 1 4 6 07891 100 II I 2 8 4 6 07891 8 4 6 01891 1000 10000 FREQUENCY IN CYCLES PER SECOND ,_ +20 +15 +10 +5 0db 0db -2 0db -2 2 aoooo 2 20 8 ,t. 6 07891 100 11!1 2 8 4 6 07891 1000 FREQUENCY IN CYCLES PER SECOND 8 4 6 07891 10000 db db :. I M/GECORD -,2 -7db- I I I 0 I I I + It

35、l t1h -:.:.-,.;.-. ,.,-tldb - - -I/ dL - RANGER 2 j 2 0 - 2db - 0 BRUSH -ldb - I I I j I j I I I +I J.J -.:-:-;- c. _,.,.,. -,.-. - _.,-_ldb I - - I ;4db RCA -3db 0 . - I +12di, . AMPEX - 11 db 2 0 t=REOllEN(;Y IN CYCI-ES PER SECOND V401 2 7 V402 Z 7 (SEE NOTE 2) V401 12SJ7 -1 R402 I MEG. SJI. +48V

36、+ISOV. C414 SPEED E-ION (SEE NOTE4) R423 lSJI, SWnal _# IOK _.5% = MOI It 115 if SPECIAL V402 R407 I MEG. I IOOIC . , R424 C406 .006 511, I R408 IOK 2W. -,2SJr c415 R410 220 R411 27K aSJI, +24SV R425 22K :._=.,.;=.;:;. I !5xoo L-_ _J NOTES: I. ALL VOLTAGES MEASURED WITH 20,000 OHMS PER VOLT METER. +

37、260V. 2. THIS TUBE SELECTED a TREATED FOR LOW NOISE. J402P 3. OUTPUT TRANSFORMER TEP, . INAL DATA IOO OHM 7 B 12 JOIN 9 a 10 ISO OHM 8 a II JOIN 9 a 10 4 EOUALlzt:D FOR PLAYBACK OF :,o TAPES RECORDED ON MODEL 200 RECGIIDER ON IIIIM TYPE 112 TAPE S MOT0II BOA TINli MAY OCCUR FOR APPROX. :,0 SECONDS W

38、HILE CONDENSER IS FORMING AFTER STANDIN!i FOR LONG PERIODS. 123456 8 I ( CHASSIS POWER l J402P PLAYBACK AMPLIFIER MODEL 201 AMPEX ELECTRIC CORPORATION r.AN CARLOS , CALIFORNIII C412 .I V405 6F6 +29!5V. p T30I G 10,000 OHM BRIDGING IN 2 - V301 C302 .I 6C5 +l35V. R30I IOOK RECORD LEVEL r5,:, 50K +250V

39、. 6C5 +250V. JUMPER TO BE REMOVED IF METER PANEL ;s ADDED I 2 3 4 5 6 7 8 9 10 II 12 (JONES CONNECTOR) J304S METER CONTROL PANEL V302 C307 V303 ,I 6C5 +l35V. 6C5 +l50V. C303 .0001 5 C308 R308 .005 50K :!:51(, C309 4X20 +250V. 450 V. _ / I 2 3 4 S i 7 8 9 10 11 12 (CHASSIS POWER) J303P + C322 10 450V

40、. R324 IOOK DUAL H F. AMPLIFIER LEVEL RECORD AMPLIFIER ERASE 6 BIAS SUPPLY MODEL 201 AMPEX ELECTRIC CORPORATION SAN CARLOS, CALIFORNIA V304 6C5 C3l0 K301 I 12V. D.C. I REtORO OUTPUT J30IP J305S BIAS- RECORD RECORD NOISE CURRENT BALANCE +270V. D.C. HEATERS V301 V302 7 2 C323 .I 600V. 11327 10.n. ERAS

41、E OUTPUT J302P :!;5% _ . J306S ERASE CURRENT NOTE: I. ALL CAMCITIES IN MICROFARADS 2.ALL VOLlllGES MEASURED WITH 20,000 OHMS PER VOLT METER 1221 TIOI F102 5A. 2!50V. . 5 ., LIOI 15h 1 c101 _1._10 -=-600V + CIO105 .25 600V. (POWER CONNECTOR) . JIOI POWER SUPPLY MODEL 201 AMPEX ELECTRIC CORPORATION SAN CARLOS, CALIFORNIA RI05 2200A RIO& IOK IOW RIii IOK IOW Cl05 ., 600V. Rt07 IOOK Cl04 2W 80 I X, J 4!50V. Rl08 47K :!:1% NOTES: I. ALL CAPACITIES IN MICROFARAOS 2. VOLTAGES MEASUREO WITH 20,000 OHMS PER VOLT METER.