This is the second device that I bought last week (see the KOSS KS5302).

This device is presenting no physical damage, and the PCB looks fine too. But, unlike the KOSS, it's partially working: the CD motor is rotating, the LCD screen has some faint scrambled data.

External case specification

  • ESA25: 25 second electronic shock absorption
  • Digital Sound Processing: 3 stage dynamic bass boost
  • Battery supply: 2 x LR6/AA/UM3
  • External supply: 4.5V - 400mA
  • Made in China

Internal ICs reference

  • SAA7374GP: Low voltage digital servo processor and Compact Disc decoder
  • AZ7395.3 87CK20AF2320: 8-bits MCU / LCD driver / timer
  • NPC SM5902AF: shock-proof memory controller LSI
  • MPC17A50: Servo driver
  • BA3574BFS: Headphone amplifier
  • 2 x HYB314400BJ-60: DRAM 4Mbit (8Mbit total)