FOR SALE ISONE (1) VINTAGE 1989 USED IBM KEYBOARD MODEL M PART NUMBER 1391401 BEIGE COLOR and ORIGINAL IBM DETACHABLE COILED KEYBOARD CABLE (SHIELDED SDL TO PS/2)MANUFACTURED IN USA BY IBM CORPORATION. ! IMPORTANT NOTE - YOU WILL REQUIRE AN ACTIVE CONVERTER (NOT INCLUDED) FOR THIS KEYBOARD TO FUNCTION, DUE TO POWER/CURRENT REQUIREMENTS (not included)! THIS KEYBOARD IS A POWER HOG, THE ACTIVE CONVERTER FROM PS2 TO USB IS REQUIRED FOR THIS KEYBOARD TO FUNCTION. HERE IS A PIECE OF COMPUTING HISTORY (i say manufacturing history), SOMETIMES CALLED THE HOLY GRAIL OF VINTAGE MECHANICAL KEYBOARDS, THIS KEYBOARD INTRODUCED TO THE WORLD IN 1989 from A MANUFACTURING FACILITY IN LEXINGTON KENTUCKY USA, THIS IS 1391401. THE MANUFACTURERS STICKER ON BOTTOM DISPLAYS MANUFACTURE DATE NOVEMBER 1989, PART NO 1391401, ID NO 5322735, DATE 18NOV89, PLT NO R1, MODEL M, MADE IN THE USA. A SEPARATE INVENTORY CONTROL STICKER DISPLAYS CHRYSLER CORP. 0018180. THIS KEYBOARD BIG BOOMED FROM MANUFACTURE birth IN KENTUCKY TO CHRYSLER CORPORATION YEARS AGO, LANDING IN AN OFFICE, OR, ON THE CHRYSLER ASSEMBLY LINE AS PART OF A MUCH LARGER FACTORY MACHINE. THIS 1391401 KEYBOARD WAS USED MUCH IN AUTOMOTIVE MANUFACTURE AND FABRICATION, OFTEN USED ON PROPRIETARY MOPAR MANUFACTURING EQUIPMENT. THIS PIECE WAS OFTEN PART OF A DESKTOP NETWORK OR EXPENSIVE MACHINE OR FACTORY SYSTEM, IN 1989 - A DESKTOP PC WOULD BE VALUED AT THOUSANDS OF DOLLARS, CHRYSLER TREATED THE PCs AND KEYBOARD AS VALUABLE ASSETS WHICH WAS COMMON THEN. THIS IBM CLICKY KEYBOARD WAS DESIGNED WHEN ABSOLUTE TYPING ACCURACY WAS STANDARD FOR CORPORATE OPERATIONS, THIS PHYSICAL PIECE OF HARDWARE WAS BUILT TO BE INDESTRUCTIBLE. THIS GENUINE IBM BRAND KEYBOARD HAS BEEN WELL MAINTAINED AND IS CLEAN, NOT PERFECT, (B or B+). Works great! YOU WILL RECEIVE ONE (1) VINTAGE 1989 IBM CLICKY KEYBOARD AND KEYBOARD CABLE, AS PICTURED, SHIPPEDBY THE ECONOMY SHIPPER OF MY CHOICE, DUE TO WEIGHT....THIS SALE INCLUDES THE DETACHABLE USED IBM SDL CABLE FEATURED IN THE PICTURES... KEYBOARDS FROM 1989 FEATURE A PROPRIETARY 6 pin SDL SHIELDED DATA LINK PORT ON THE BACK, WHICH SPLITS OUT INTO A STANDARD COILED PS/2 CONNECTOR. NOTE - YOU WILL LIKELY REQURE AN * ACTIVE * ADAPTER SINCE THIS KEYBOARD HAS ADDED POWER REQUIREMENTS (this keyboard is a power hog). THE LIGHTS, THE CURRENT REQUIREMENTS CANNOT BE PROVIDED THROUGH THE INCLUDED CABLE, AN ACTIVE CONVERTER IS ALWAYS REQUIRED! (NOT INCLUDED HERE)
adhesive sticker on bottom of keyboard reads...PART NO 1391401
ID NO 5322735
DATE 18NOV89
PIT NO R1 MODEL M
MADE IN THE USA2nd adhesive sticker on bottom of keyboard reads...CHRYSLER CORP.
0018180basic specifications,

• Key Switch Type: IBM patented membrane buckling springs.
• Layout: Standard 101-key ANSI U.S. English layout (which set the standard for modern layout geometry).
• Keycaps: Thick, two-piece PBT plastic with highly crisp, permanent dye-sublimated legends.
• Connection Type: A specialized 6-pin SDL (Shielded Data Link) port on the keyboard that connects to a coiled PS/2 cable.
• Weight: Nearly 5 pounds (approx. 2.2 to 2.5 kg)

The Buckling Spring PhenomenonInstead of a modern linear or tactile switch, this Model Mutilizes a literal physical spring under every keycap. As you press down, the spring compresses until it abruptly buckles (snaps outward) halfway through the keypress. This forces a small plastic hammer to click against the internal circuitry. The result is an intensely satisfying mechanical "clack" and a crisp tactile bump that hit exactly at the moment of actuation, letting your fingers instinctively know the key has registered.2. Peak "Made in the USA" EngineeringA 1989 Model M features the highly sought-after "Grey Oval" IBM badge on the upper-left corner. During this specific period, IBM used a heavy-duty, thick internal steel backplate inside the chassis. Because of this internal metal plate, the keyboard feels like an absolute tank, possesses zero chassis flex, and produces a deeper, lower-frequency sound resonance compared to the lighter plastic variants manufactured later in the mid-to-late 1990s.3. Two-Piece PBT KeycapsUnlike modern cheap keycaps that turn yellow and smooth out over time, the Model M uses PBT plastic that resists skin oils and UV light. The two-piece design allows you to pop off the outer keycaps to reveal an inner stem structure. The legends (the letters on the keys) are dye-sublimated, meaning the ink is fused directly into the plastic—they will virtually never wear away, even after decades of continuous typing.
This keyboard natively sends signals via a PS/2 protocol. Because modern computers lack standard PS/2 ports, a generic passive green plastic adapter usually won't work. To use it today on Windows, Mac, or Linux, you will need anactive, signal-converting PS/2 to USB adapter.
offer AND BUY HERE IN IN ABSOLUTE CONFIDENCE SINCE I HAVETHOUSANDS OFPOSITIVE response AND TEN+ YEARS EXPERIENCE. I SHIP WITHIN TWO DAYS OF RECEIPT OF PAYMENT, OFTEN THE NEXT DAY. $5.81 ECONOMY GREEN SHIPPING USING RECYCLED PACKAGING MATERIALS AND ENVIRONMENTALLY FRIENDLY MATERIALS TO ANYWHERE USA.IDO NOT SHIP ANYWHERE ELSE. HAVE A GREAT DAY AND THANK YOUFOR STOPPING BY.....