Sharp MD-MT77 / MD-MT877

~~ Sharp MD-MT77 / MD-MT877 ~~

Portable MDLP Recorder

In 2000, Sony announced MDLP (MiniDisc Long Play), which added new recording modes based on a new codec called ATRAC3. In addition to the standard, high-quality mode, now called SP, MDLP adds LP2 mode, which allows twice as much recording time (160 minutes on an 80 minute disc) of good-quality stereo sound, and LP4, which allows four times more recording time (320 minutes on an 80 minute disc) of medium-quality stereo sound. The bitrate of the standard SP mode is 292 kbit/s, and it uses separate stereo coding with discrete left and right channels. LP2 mode uses a bitrate of 132 kbit/s and also uses separate stereo coding. The last mode, LP4 has a bitrate of 66 kbit/s and uses joint stereo coding. The sound quality is noticeably poorer than the first two modes but is sufficient for many users. Tracks recorded in LP2 or LP4 mode playback as silence on non-MDLP players. Sony announced they would cease development of MD devices, with the last of the players sold by March 2013{wikipedia} 

Introduction

The  MD-mt77 / MD-mt877 is the successor of the MD-mt66 / MD-MT866, therefore, they are very similar to one another in many ways the mt66 is like the mt77 excluding the ability to play MDLP format disc. The MD-mt77 was titled "MD-J" in Japan and it was very successful. The X-BASS Boost is quite rich and well balanced when compared to its competitors. Overall, Sharp was a little soft and had a grand taste. The mt77 design is very sophisticated in the same Sharp tradition (like the mt66 model) it looks that they were thinking of the overall experience from A to Z down to the box* (see accessories & Packaging), every aspect was taken into consideration. For example, the unit color is something very unique; it changes color if you look at it from a different angle, sometimes it appears blue or green/tourqize. which make it a very cool unit to walk with. one more example is the charging cradle which has a holder for the remote control for your convenience. Also, there is 3 color LED ("Navi" in Japanse) which indicates various modes of operations.

This picture shows the shift in color, on the Left: SHARP MD-mt877 appears blue. In the middle is the "MD-J" MD-mt77 appears to be Greener. On the right is the Silver MD-mt877.

Features

Smallest portable MDLP recorder in the world as of October 2000. 

The MD-mt77 is the first Sharp MDLP player. It has Two-line 12-character LCD display, 40-second shock protection (provides 160-second protection in LP4 mode), digital recording level control,  Microphone-synchronized recording function only records when sound is heard. Mono mode recordings can be played back at 2x speed. "Scan" feature plays the first five seconds of each track. Track "auto-mark" function can be set to mark a track at regular intervals (3, 5, and 10 minutes). "Name Stamp" function allows easy copying of character information from one disc to another. Can interface with a computer via USB connection kit (AD-PCR2), allowing track and title management and automatic label printing of a MiniDisc's contents, as well as an audio connection. Battery "memory effect" is reduced by automatic discharging circuitry in the charging stand. X-BASS boost.

MD Link with the USB Cable

• LSI Hologram Chipset (Sharp ATRAC3) 
• 24 bit DAC and ADC.
• 40-second shock memory.
• Optical input.
• 3 color LED light shows the operating condition.
• 3 modes Bass boost.
• Top open (clam-shell) disc insertion.
• Back-lit LCD remote control.
• Analog and digital recording levels.
• Mic and digital synchronous start recording.
• Disk/track "name stamp" function allows titles to be cloned from another disc.
• 2 x high-speed playback option on mono recordings.
• Auto Play function and Auto Power Save function.
• Conferencing Voice-activated recording.
• Charging stand for the supplied flat Nickel-Metal Hydride battery.
• The Unit can be operated while recharging.
• Available in silver (-S) and blue (-A).

MD-mt877 Remote Control

Pages from the owners manual

Power Source

Charging time: Approx. 3.5 hours. 

• 12 hours playback, or 6.5 hours of recording, on a rechargeable battery.
• 16 hours playback, or 6 hours of recording, on a single AA external battery. 
• 29 hours playback, or 15 hours of recording, on a rechargeable battery and the external battery case. 
• 1 AA size battery using the supplied Battery case. 
• 1 NiMH rechargeable battery.
• Adapter - DC 5V
• Power consumption 7W. (AC Adaptor)

The MD-mt877H Charging Station

Accessories & Packaging

While the Universal box was a very attractive colorful box, the Japanese box was actually two different kind of boxes following the two colors available units; the silver unit was silverish-gray the blue unit was blue.

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  Sharp MD-mt877H - The world Box

• Charging Cradle
• LCD remote, earphones
• Li-Ion cell, AC adapter
• Optical cable
• Connection cord
• AA cell case
• Hand strap, carrying case
• Instruction manual, Warranty card

Sharp MD-mt877H World version Unboxed and the Owners Manual

Specifications:

SHARP MD-mt77 MDLP - Press Realese

• Size:                                                  D: 78.7 x W: 71 x H: 16.8 mm.
• Weight:                                           131 g with rechargeable battery cell
                                                             116 g without rechargeable battery cell

■ AUDIO

• System name:                              SHARP MD-mt77 S/- (silver) A/- (blue)
• Reading method:                       Non-contact optics reading method                                                                                  (semiconductor laser use)
• System:                                           MiniDisc digital audio system
• Recording system:                     Magnetic field modulation direct overwrite
• Laser:                                              Semiconductor laser (785 nm) 
• Sampling frequency:                44.1 kHz (32 kHz & 48 kHz are converted to                                                                44.1kHz and then recorded)
• Sampling rate converter:       32 kHz/44.1 kHz/48 kHz
• Coding:                                           ATRAC 24-Bit computed Type 
• No. of Channels:                         2 (left and right, stereo),  (long play) 1
• Frequency response:                20 Hz - 20,000 Hz (±3dB)
• Wow and flutter:                       Unmeasurable (less than ±0.001% w. Peak)
• Headphone amp:                       RMS: 10 mW = 5 mw + 5 mw  (0.2% T.H.D.)
• Phone jack Impedance:         32Ω

Service Manual

Pages from the MD-mt877H Service Manual

This MDLP is the First SHARP MDLP unit and One of the Best out there.....

(Hopefully more revising will follow)

Coming up........................................

AIWA HS-P77 / HS-P70

AIWA  HS-P77 / HS-P70

AIWA CassetteBoy HS-P77  Japanese Red Version
(from 1985 the successor of the successful and famous HS-P7 /HS-P07 /HS-P02MkII)

Have It Both Ways! 

Quality Extras and Auto Reverse in a Super 
(    (   (  (  ( (((   Slim Design   ))) )  )  )  )   )

Want a player that’s light & compact, or one with extra features? 

AIWA’s HS-P77 lets you have it both ways. You get 3-way auto reverse and the superb fidelity of Dolby B, all in a slim and light player that weighs just 260 grams— including batteries! Just 25.3mm thin, the HS-P77 sets the standard in ultra-slim auto reverse players. Auto Reverse Convenience Just 80mm by 110mm, the HS-P77 slips easily into all but the smallest pockets. Once it’s in, you won’t have to pull it out every time the tape finishes thanks to 3-way auto reverse. The reverse mode switch enables continuous or one-cycle auto-reverse operation, while manual reverse at any time requires just a single touch.

Compact pocketability or extra features?

Now there’s no need to choose because AIWA's HS-P77 gives you both. You get the extended playback of 3-mode auto reverse, the superb fidelity of Dolby B noise reduction, and the convenience of cue & review—all in a slim and light player. Weighing just 260 grams with batteries, and measuring only 80 x 110 x 25.3mm, the HS-P77 sets a new standard in ultra-thin cassette players. It's the ideal pocket music companion you’re sure to take with you wherever you go.

Aiwa's smallest auto-reverse player
Just 80 mm wide and 110 mm high, it slips easily into all but the smallest pockets. Slim enough to slip into most any pocket, the HS-P77 weighs only 260 grams with batteries. And thanks to auto-reverse convenience, you’ll never have to turn the tape over at the end of each side, because the HS-P77 does it for you—automatically. During play, a single touch reverses tape direction and plays the other side. 

Snippet from: Aiwa Personal Stereo Catalog 1985

The HS-P77 is the result of AlWA’s long and serious dedication to quality miniaturization.
With such compact convenience, it's your own personal companion for music enjoyment—no matter which direction you're going!

AIWA HS-P77 Green version with the Original Earphones: the plastic on the front panel designed for a better grip. Even though Aiwa designed it to tuck it in a shirt pocket, the plastic grip is really the opposite message - to hold it while you enjoying it!

Dolby noise reduction and more for improved fidelity

Dolby B is the most widely-used system for improving playback fidelity.
Now you can enjoy better quality sound because the HS-P77 has Dolby B noise reduction to provide low-hiss playback of Dolby-encoded tapes. For extended frequency response from high-performance Metal and CrO2 tapes, the HS-P77 has a Normal/Metal (CrO2) tape selector which allows the proper playback equalization for all types of tape. Finally, AlWA’s low-noise coreless DC servo motor and quality drive system contribute to the quiet and stable tape drive for minimal wow and flutter.

AIWA HS-P77: This model have a plastic Stop button different from the others because it also uses as the Cassette Eject

Anti-rolling mechanism for extra stability

Whether you’re jogging, bicycling or dancing, tape playback won’t be disturbed by annoying wow caused by changes in position: The special anti-rolling mechanism employs a pair of large flywheels to absorb changes before they can affect tape run.

PLUS:

•Cue & review
•Metal (CrO2)/Normal tape type selector
•Auto stop in Play mode; silent off in FF and Rew modes
•Convenient reverse mode selector plus manual reverse switch
•Extended battery life—up to 8 hours with two UM-4 (AAA) alkaline batteries
•High-performance lightweight headphones
•AC operation with AlWA’s optional AC-620 AC adaptor
•Supplied with belt hanger, carrying case, and shoulder strap
•High-fidelity headphones, carrying case and belt hanger supplied
•HS-P77 - 7 Colors: Silver, Black, Red, Pink, Green, Blue & White
•HS-P70 - 3 Colors: Silver, Red, Black

Snippet from: AIWA AUDIO & VIDEO Japanese Catalog June 1986

AIWA HS-P77 Green Version with it's Protective Carrying Case

HS-P77 SPECIFICATIONS:

TYPE: Ultra-compact auto reverse stereo cassette player
POWER SOURCE:  
DC: 3V, battery size "AAA", R-03 or UM-4 x 2.
AC: through AC adaptor AC-620.
FREQUENCY RESPONSE: 40 ~ 16,000Hz (Metal tape)
MOTOR: Coreless DC servo motor
DIMENSIONS: 80(W) x 110(H) x 25.3(D)mm (3-13/16" x 4-3/8" x 15/16")
WEIGHT: 245g (8.7 ozs) without batteries
ACCESSORIES: Stereo Headphones, Carrying case, Belt hanger, and Shoulder strap.

Right: "POCKET SIZE STEREO" - HS-P70 Boxed. Left: AIWA June 1986 - HS-P70. 

AIWA HS-P77 - Super Permalloy Head (PH)

Technical info:


<CASSETTE PLAYER SECTION>
Track type: 4 tracks, 2 channels
Tape speed: 4.8 cm/s.(1 7/8 ips)
Signal to noise ratio: 50± 4dB (DC/AC) PB (Unweighted)
Frequency response: 40~12,500Hz (NORMAL)
40~16,000Hz (METAL)
Output power: 20 mW + 20 mW (EIAJ/DC)
Noise level: less than 8 mV / 
Less than 9 mV (DC/AC VOL. MAX)
Distortion: Less than 2.5% (PB)
Motor: Coreless motor
Head: Super permalloy head (PH)
Automatic stop system: Mechanical auto, FF/REW motor
Automatic stop time: less than 2 s.
Wow & flutter: 0.3% (WRMS)
Pinch roller pressure: 170 ± 10g (1.67± 0.09N)
Take-up torque 25g-cm (2.45mN • m)
FF/Rewind torque 90± g-cm (8.82± 2mN .m)
Rewind/FF time: 130± 20 s. (C-60)

Output: Headphone jack (3.5 Ø)


<HEADPHONE SECTION> 
Type:  Dynamic type
Impedance:   29 ohms
Frequency response:   50~20,000 Hz
Sensitivity:   107 dB/mW
Maximum input:   100 mW

More to come...............