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Hewlett Packard 82161A Digital Cassette Drive

• Type: Optional Calculator Accessory
• Size: 7 x 5.25 x 2.5 in / 18 x 13 x 6 cm
• Serial number: 2338A03140
• Date of Manufacture: September 1983

HP-IL based mass storage device. Each microcassette would store some 16000 registers (around 128K). These were not the microcassettes found in dictation machines; nothing else were like these. I have three, all seem to be bad. The compartment on the left holds two cassettes in storage.