Otari MX-5050
Parts →Accessories →

Updates

What is new to read here, newest first. Not the same thing as the restoration log, which is what happened at the bench — this is what has been added to the site. New content and selected standalone tools are dated from site history; corrections worth knowing about are written down by hand. Figure redraws and typo fixes are not news and are not here. Atom feed.

October 2026

  1. Updated

    Section 7 schematics and PCB X-ray views, redrawn

    Now vectors, traced from his Paint.NET layers, so the sheets stay sharp at any zoom.

  2. New

    A home-made CR-705 remote with a light for every function

  3. New

    Capstan speed change and power supply connector

  4. New

    Gold-plated C&K pushbutton switches

  5. New

    Rebuilding the interconnection cable

  6. New

    Recapping the whole QXHD

  7. New

    Section 7 schematics and PCB X-ray views, redrawn

  8. New

    Smaller mods, and a record lamp that will not blink

  9. New

    Take-up reel motor: poor fast forward

  10. New

    The $65 rescue: a stuck pinch roller and an LED retrofit

  11. New

    MX-5050B — 5 new documents

  12. Updated

    Parts Lists and Schematics

    Exploded views, pin identification, block diagrams and the head assembly wiring re-cut from a 600 dpi scan of a paper copy, an original print rather than the earlier photocopy. The block diagrams' full-resolution copies are now 600 dpi. The five schematic sheets are still from the earlier scan.

  13. New

    AMP control board in KiCad (PB45E0A, drawing 3-6649)

  14. Updated

    Parts Lists and Schematics

    Added this site's KiCad redraw of the AMP control board drawing 3-6649 (PB45E0A) under its scan, with a PDF, the KiCad project to download, and a page of simulation results.

  15. New

    Sales sheet S-110A — MX-5050-8 Compact Eight Channel Recorder (January 1978) — 3 new pages

  16. Updated

    Parts Lists and Schematics

    Added all nine drawings in the BQ-II manual's schematic index, each with a PDF to download: six fold-out sheets joined from 600 dpi scans, two loose sheets scanned at 1200 dpi, and the head connection diagram from the last page. Their board numbers are now in the parts finder.

  17. New

    The BQ-II manual arrived

  18. New

    How this site was built

  19. New

    Parts Lists and Schematics

September 2026

  1. New

    First Weekend AES Wins a Solid ‘Yes’ Vote

  2. New

    From Our Hands To Jeff Baxter's

  3. New

    From Our Hands To Jeff Baxter's

  4. New

    ITA–Europe's Leading Distributor of Multitrack Equipment

  5. New

    KEVIN CRONIN ON MAKING IT: ON AN OTARI.

  6. New

    New York—AES 52nd Convention

  7. New

    Otari 5050 Mark III/8

  8. New

    OTARI AND TASCAM EIGHT-TRACK/HALF-INCH TRANSPORTS

  9. New

    OTARI INTRODUCES NEW GENERATION HALF-INCH EIGHT-TRACK RECORDERS

  10. New

    Otari MX 5050

  11. New

    Otari MX-5050-MKIII-8 Professional Reel-to-Reel Recorder

  12. New

    Otari MX5050-Mk III/8

  13. New

    PLAY OTARI

  14. New

    Professional Performance at Popular Prices!

  15. New

    WISHING MADE IT SO.

  16. New

    “Having witnessed the sophistication of our new 24 track Otari in Gooseberry 2, we felt confident in relying on the MX5050B for stereo mix-down.”

  17. New

    “Once you get your hands on this machine . . . you’ll see what we mean.”

  18. New

    “SOLUTIONS, SOLUTIONS, SOLUTIONS. . .”

  19. New

    “SOLUTIONS, SOLUTIONS, SOLUTIONS. . .”

  20. New

    3 Greats from Otari!

  21. New

    An Otari Varispeed Modification

  22. New

    ANALOG MULTITRACK RECORDERS

  23. New

    As Good As You Are.

  24. New

    Available, in St. Louis, only at Antech Labs.

  25. New

    Birth of the two-track masterpiece. Otari MX5050·B.

  26. New

    Dollars For dB's, It's The Best You Can Own.

  27. New

    Doubly effective

  28. New

    Dynamic Workhorse

  29. New

    FROM OUR HANDS TO YOUR HANDS

  30. New

    IN 1994, YOUR STATION IS SURE TO HAVE ONE FAMILIAR FACE.

  31. New

    INDUSTRY STANDARD CHAPTER II

  32. New

    INDUSTRY STANDARD CHAPTER II

  33. New

    Intriguing Transformer

  34. New

    It's The Best Selling Professional Tape Machine In The World.

  35. New

    ITA. The One Source.

  36. New

    Let's Make a Deal

  37. New

    Mark II: history

  38. New

    MARK III: history

  39. New

    MARK IV: history

  40. New

    MX-5050 B-II: history

  41. New

    MX-5050 B-III: history

  42. New

    MX-5050-B TWO CHANNEL RECORDER

  43. New

    MX-5050B: history

  44. New

    MX-5050s are Hard Workers

  45. New

    New Products — Tape Recording Update

  46. New

    ONE LESS ALLIGATOR

  47. New

    Otari 2-Track Bound for Seoul

  48. New

    Otari Adds Features to MX-5050s

  49. New

    OTARI BROADCAST RECORDERS

  50. New

    OTARI from ITA

  51. New

    Otari MX-5050 improvements

  52. New

    OTARI MX-5050-B BROADCAST RECORDER

  53. New

    Otari MX-5050-B Open Reel Tape Recorder

  54. New

    OTARI MX5050 BQII — The first compact 4 track for the serious user

  55. New

    OTARI MX5050B — the stereo recorder for the eighties.

  56. New

    OTARI MX5050BIII

  57. New

    Otari's MX-5050 Series

  58. New

    Otari's Son of MX-5050

  59. New

    Professional Performance With A Bottomline Benefit.

  60. New

    RADIO'S TOP TEN!

  61. New

    RADIO'S TOP TEN! OTARI GIVES YOU BETTER CHOICES.

  62. New

    Recording Excellence

  63. New

    Still The Best Investment In A Professional Two Channel Tape Machine.

  64. New

    the best $3000 two channel recorder for under $2000*

  65. New

    THE BEST VALUE IN A PROFESSIONAL TAPE RECORDER

  66. New

    The Machine That Sold the Salesman

  67. New

    The new ¼·inch 2·track recorder with a finish.

  68. New

    the New Workhorse

  69. New

    THE NEXT “WORKHORSE.”

  70. New

    THE OTARI 5050 RANGE.

  71. New

    The Otari 5050B-II With The Proof Of Performance

  72. New

    The Otari Machine — Performance Reliability & Value

  73. New

    The Right Tool For Every Broadcast Application

  74. New

    Tracks to Glory

  75. New

    USED EQUIPMENT TAPE RECORDERS part 3

  76. New

    What We Did For SOUNDTREK STUDIOS

  77. New

    Why Otari’s ‘fifty-fifty’ series is really one hundred percent on the button

  78. New

    Donor-parts cross-reference

  79. New

    Multichannel MX-5050 models

  80. Updated

    Identify your MX-5050

    Added the model-code lookup and family photo comparisons, with the supporting sources grouped by family.

  81. New

    Instruction manual (OS1-011)

  82. New

    Mark II preliminary specification sheet (S-114, November 1976) — 2 new pages

  83. New

    Mark II: specifications

  84. New

    MARK III/2 operation manual, OS3-042 (Edition 3, February 1986; incomplete scan)

  85. New

    OEM accessory compatibility finder

  86. New

    Operation and maintenance manual (OS3-298, 3rd edition, May 1992)

  87. New

    Speed adjustment bulletin (TB-5050-001)

  88. New

    The Mark II sheet arrived

  89. New

    Video Images Reference Catalog 1988–89 — Otari listing

  90. New

    MARK IV: specifications

  91. New

    MX-5050 B-II: specifications

  92. New

    MX-5050 B-III: specifications

  93. New

    MX-5050 Series data sheet (OA-321C, 1991) — 3 new pages

  94. New

    MX-5050B: specifications

  95. New

    Operation and maintenance manual (OS3-298, 4th edition, December 1997) — 11 new pages

  96. New

    Alignment procedures, BII and MKIII-2 (Edition 2, January 1988) — 5 new pages

  97. New

    Instruction and maintenance manual (OS3-035) — 9 new pages

  98. New

    Instruction manual (OS3-038, Edition 6, September 1984) — 11 new pages

  99. New

    MARK III: specifications

  100. New

    The MARK III Series brochure (1984) — 6 new pages

  101. New

    Chris's QXHD

  102. New

    First generation — 2 new pages

  103. New

    Instruction and maintenance manual (OS3-031) — 9 new pages

  104. New

    Instruction and maintenance manual (OS3-035) — 2 new pages

  105. New

    Mark II — 2 new pages

  106. New

    MARK III — 2 new pages

  107. New

    MARK IV — 2 new pages

  108. New

    MX-5050 B-II — 2 new pages

  109. New

    MX-5050 B-III — 2 new pages

  110. New

    MX-5050-2S

  111. New

    MX-5050B — 2 new pages

  112. New

    Instruction and maintenance manual (OS3-031) — 2 new pages

  113. New

    Maintenance manual (OS2-004) — 2 new pages

  114. New

    Paper in the post

  115. New

    Sales brochure — MX-5050-B, all-new compact professional recorder (107-9-79, September 1979) — 4 new pages

  116. New

    Synchronizer interface information (Edition 1, May 1985) — 3 new pages

  117. New

    Maintenance manual (OS2-004) — 5 new pages

  118. New

    MARK III — 2 new documents

  119. New

    MX-5050 B-II — 2 new documents

  120. New

    MX-5050 BIII product sheet (© 1999, 2008)

  121. New

    Service bulletin: DD capstan motor lubrication (June 1989)

  122. Updated

    The meters mean something now

    Corrected: the output level switch is not out of circuit. Its pad only acts into a load, and the multimeter isn't one — thanks to u/fruhfy.

  123. New

    Zero in, zero out

  124. New

    Maintenance manual supplement (OMM-1002E) — 2 new pages

  125. New

    Five decibels hot at 10 kHz

  126. Updated

    Five decibels hot at 10 kHz

    Corrected: this was the first alignment since the recap, not the first ever.

  127. New

    Maintenance manual supplement (OMM-1002E) — 4 new pages

  128. New

    Instruction and preventive maintenance manual (OIM-1004E) — 2 new pages

  129. New

    Instruction and preventive maintenance manual (OIM-1004E) — 4 new pages

  130. New

    MX-5050BII: the one people mean when they say MkII

  131. New

    The announcer was slow

  132. New

    The meters mean something now

  133. New

    The reference tapes, at the right speed

  134. New

    Mark II: the MX-5050 in two boxes

  135. New

    MX-5050-8 / 8D: the half-inch eight-track

  136. New

    MX-5050B: the plain B

  137. New

    QX / QXD / QXHD: the quarter-inch four-channel

August 2026

  1. New

    First generation — 3 new documents

  2. New

    Operation manual (OIM-1005E) — 5 new pages

  3. New

    The operation manual surfaces

  4. New

    The reference tapes arrive

  5. New

    Sales brochure — Compact Professional Recorder (S-117A, April 1978) — 5 new pages

  6. New

    Sales brochure — Compact Professional Tape Recorder (B-103A, September 1975) — 4 new pages

  7. New

    The first brochure: Specification Sheet S-111

  8. New

    The other two brochures

  9. New

    Specification Sheet S-111 (August 1976) — 4 new pages

July 2026

  1. New

    Paper arrives

  2. New

    Recap complete

  3. New

    Choosing the audio capacitors

  4. New

    The playback-first recap: a bench guide

  5. New

    The eight parts that keep the switches alive

  6. New

    Annual Equipment Directory: the Otari listings

  7. New

    Full professional performance and features in a compact package — Otari MX-5050

  8. New

    Three new professional recorders from Otari

  9. New

    9 outstanding reasons why you should choose Otari

  10. New

    Equipment Profile: Otari MX-5050-2SH

  11. New

    Front Matter

  12. New

    Mini-Pro! Little brother to the MX-7000 — the MX-5050

  13. New

    Otari listings

  14. New

    Otari MX-5050 Professional Series Two-Speed Tape Recorder

  15. New

    Otari Will Adapt Retailing Modes

  16. New

    Service training binder — 6 new pages

  17. New

    Survey: Studio Mastering Machines — the Otari entries

  18. New

    Inside the transport buttons

  19. New

    Maintenance manual (2S, 4S, 2SD & 4SD) — 6 new pages

  20. New

    New Products: the Otari MX-5050

  21. New

    Finding the schematic

  22. New

    First generation — 3 new pages

  23. New

    Identify your MX-5050

  24. New

    Listed as broken. The adventure begins.

  25. New

    No dummy plug — no problem!

  26. New

    Re-capping the motor run caps