Sanyo Micro Pack 35

The Sanyo Micro Pack 35 was a portable, battery-operated magnetic audio recorder developed by Sanyo in 1964. Styled to resemble a small film camera, it was marketed as a compact “sound camera” for making personal recordings, capturing children’s first words, entertaining guests, and sending spoken messages. Rather than using a conventional open reel or the emerging Compact Cassette format, the device employed a proprietary transparent tape cartridge in which the two reels were positioned one above the other. The recorder was designed around portability and simplicity. Its cartridge measured approximately 2.6 by 2.9 by 1.9 inches and contained quarter-inch magnetic tape. A typical cartridge associated with the Channel Master version held 250 feet of tape. The tape followed a diagonal path across tilted rollers, while the recording and erase heads were mounted at a corresponding angle. The cartridge supported monophonic recording, with one track used on each side. Conductive marks near the ends of the tape automatically stopped transport; a top-mounted control could override the stopping function and permit operation in the reverse direction. The transport mechanism was unusual. The unit did not use a conventional capstan. Instead, the motor shaft entered the cartridge between the reels and pressed against a rubberized surface. The motor assembly tilted in opposite directions to engage one reel or the other, thereby selecting tape direction. Because the effective reel diameter changed as tape accumulated on or unwound from a reel, tape speed was not constant. The resulting wow and flutter could reach roughly one percent. A top control offered Slow and Fast settings, allowing the user to trade recording duration against sound quality. The Micro Pack 35 included a microphone input, an earphone output, and an internal speaker. Its VU meter served both as a recording-level indicator and, during playback, as an indicator of the remaining charge in the four AA batteries. These features made the product practical for casual voice recording, but its transport instability and limited low-frequency response made it poorly suited to music. The format also entered the market approximately a year after the Compact Cassette, which benefited from broader industry adoption and ultimately displaced competing proprietary cartridge approaches. The device was also sold under other names. A rebadged version appeared as the Channel Master 6546, using a cartridge identified as Model 6595, and another version was marketed as the Westinghouse H29R1. The product and its cartridge system had limited commercial longevity and are now principally of interest to collectors of early portable recording technology. An unbranded example was briefly visible in the 1967–1968 television series The Prisoner, in the episode “The General.”

Sanyo developed the Micro Pack 35 in 1964 during a period when consumer audio manufacturers were seeking smaller and more convenient alternatives to conventional reel-to-reel recorders. The product was conceived as a portable “sound camera”: its exterior and controls evoked a compact film camera, while its intended uses emphasized personal messages, family recordings, and casual entertainment rather than professional audio production. Its defining technical feature was a proprietary cartridge with two reels arranged vertically. The transparent plastic cartridge enclosed approximately quarter-inch magnetic tape and guided it diagonally across tilted rollers. The recorder used a single monophonic track on each side of the cartridge. Conductive tape markers stopped the mechanism at the end of a side, and a manual override permitted the user to continue in the opposite direction. This design made loading and handling simpler than working with loose reels, while retaining a reel-to-reel-like tape path inside the cartridge. The transport system was particularly unconventional. There was no capstan to maintain a fixed tape speed. Instead, a motor shaft pressed against a rubber-coated area between the reels. Tilting the motor caused the shaft to engage one reel or the other, selecting forward or reverse movement. Since the changing diameter of the tape pack altered the transport rate, speed varied during operation and produced significant wow and flutter. Users could select Slow for longer recording time or Fast for improved quality and shorter running time. The recorder offered a microphone socket, an earphone socket, an internal loudspeaker, and a meter that monitored recording level and indicated battery condition during playback. The Micro Pack 35 entered a market that was becoming increasingly shaped by standardized formats. The Compact Cassette had appeared roughly a year earlier, and its industry-backed format eventually achieved much wider adoption. By comparison, the Micro Pack system remained proprietary and its mechanical limitations reduced its usefulness for music. Its frequency response and speed stability were more appropriate for spoken-word notes and informal voice recordings than for musical listening. These factors, together with the difficulty of competing against a rapidly standardizing cassette ecosystem, limited the format’s market life. Sanyo’s recorder was rebadged for other companies and markets. The Channel Master version was sold as the Channel Master 6546 and used a cartridge designated Model 6595; a further rebadged version appeared as the Westinghouse H29R1. These variants demonstrate that the product was distributed beyond a single Sanyo-branded channel, although the available reference material does not establish a complete sales geography or production volume. The product later acquired a modest afterlife among vintage-electronics collectors and enthusiasts interested in obsolete recording formats. An unbranded version appeared briefly in the 1967–1968 television series The Prisoner, in the episode “The General.” Today the Micro Pack 35 is remembered less as a successful mass-market standard than as an inventive transitional design that illustrates the experimentation surrounding portable magnetic recording before compact cassette technology became dominant.

• 1967

  Appearance in The Prisoner

  [1]Sanyo Micro Pack 35en.wikipedia.org

  An unbranded version of the recorder is briefly shown in the television episode “The General.”

• 1964

  Sanyo develops the Micro Pack 35

  [1]Sanyo Micro Pack 35en.wikipedia.org

  Sanyo develops a compact portable magnetic recorder using a proprietary cartridge with vertically stacked reels and a camera-inspired enclosure.

• 1964

  Proprietary Micro Pack cartridge format enters the market

  [1]Sanyo Micro Pack 35en.wikipedia.org

  The recorder is offered with transparent cartridges containing quarter-inch tape for single-track-per-side monophonic recording.

• Rebadged versions appear

  [1]Sanyo Micro Pack 35en.wikipedia.org

  The recorder is marketed under the Channel Master 6546 and Westinghouse H29R1 names.

A compact personal voice recorder positioned as a camera-like, easy-to-carry “sound camera” for informal speech recording and playback rather than high-fidelity music.

• Portable magnetic audio recorder · 1964

  Sanyo Micro Pack 35

  A compact, battery-powered monophonic reel-to-reel-style recorder enclosed in a camera-like body. It used a proprietary transparent cartridge with stacked reels, microphone input, earphone output, internal speaker, and a meter for recording level and battery condition. Its capstanless transport used a tilting motor shaft to select direction, producing variable tape speed and substantial wow and flutter.

• Magnetic tape cartridge · 1964

  Micro Pack tape cartridge

  A transparent plastic cartridge measuring approximately 2.6 by 2.9 by 1.9 inches. It held quarter-inch tape on vertically arranged reels, with the tape guided diagonally across tilted rollers. The format provided one monophonic track per side and used conductive end markers to stop the recorder automatically.

• Rebadged portable tape recorder

  Channel Master 6546

  A rebadged version of the Sanyo recorder sold under the Channel Master name. Its associated cartridge was identified as Model 6595 and reportedly contained 250 feet of tape.

• Rebadged portable tape recorder

  Westinghouse H29R1

  A Westinghouse-branded version of the Micro Pack 35 platform. The available reference material identifies the model as a rebadge but does not provide additional specifications or market details.

• 1964

  Launch of a proprietary portable recording formatProduct launch

  Background

  Sanyo sought to make reel-based magnetic recording more portable and approachable through a compact camera-style recorder and enclosed cartridge.

  Action taken

  The company introduced the Micro Pack 35 with a custom transparent cartridge, simplified transport, microphone input, earphone output, and internal speaker.

  Aftermath

  The format remained a niche design. Its speed instability and limited low-frequency response reduced its suitability for music, while the competing Compact Cassette gained broader market acceptance.

  Source

• Use of rebadging to broaden distributionStrategy

  Background

  The proprietary format required access to additional brands and distribution channels to reach consumers.

  Action taken

  The recorder was sold under the Channel Master 6546 and Westinghouse H29R1 names.

  Aftermath

  The available sources do not document the commercial results of the rebadged versions, but the format ultimately did not become a durable mass-market standard.

  Source

1. 1Sanyo Micro Pack 35en.wikipedia.org
2. 2Forgotten Format: SANYO Micro-Pack 35 Tape Recorderyoutube.com
3. 3Sanyo Micro-Pack 35 picture galleryvintage-technics.ru