NCR 4950

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NCR 4950
Ncr 4950 top.jpg
Model no. 4950 2920-9002-9000
Branding NCR
Manufacturer Hi-Tek Corporation
Features ADDS terminal compatibility
Keyswitches Alps SKCL Green
Hi-Tek Series 725
Omron B3G-S series
Interface RJ-11 male cable non-removable

NCR 4950 is a keyboard from NCR Japan which uses a number of switch types.

Description

Internally the keyboard seems to be capable of speaking either an ADDS terminal protocol or standard PC AT, depending on how it was configured at the factory; the configuration is set using wire links on the controller PCB. With the PC/AT-configured model, a simple rewiring of the cable to a 5-pin connector will make the keyboard usable with a modern computer with the assist of a PC AT/USB converter.

The keyboard features a custom layout with no navigation cluster, but a numeric keypad is included. A horizontal space for a function key template resides at the top.

Two Hi-Tek switch types have been found: two-eye white (shown below) and two-eye black switches that seem to have had the click arm omitted to provide a linear feel.[1] There are two other variants using Omrons and SKCL green switches respectively. For the former, at least one example has been spotted using White Omrons.[2]

Rebrands

The ADDS ASCII is a rebrand of this keyboard with the badge of ADDS, an NCR subsidiary. This version has been spotted using Hi-Tek Series 725 switches.

Gallery

NCR 4950 with Hi-Tek Series 725 switches

The controller chip is marked "9308" and one of the support chips (from Hitachi) is marked "3B16" (February in a year ending 3), so this appears to be a early 1993 production.

ADDS ASCII with Hi-Tek Series 725 switches

NCR 4950 with Alps SKCL Green switches

The timestamp on the bottom cases suggested that this keyboard was made in August 1987. No meaningful conclusion about the manufacturer of this board can be drawn at the moment.

Converter

Switching the board to PC/AT mode can be done via jumpers being installed only in the following locations: JP1-JP4. Soarer's converter can be used with either a Teensy or Pro Micro to internally convert the board to USB. The variant with SKCL green has not been tested with this approach.

pin# Top
6 Reset Red
5 Data Green
4 Case GND
3 Clock Yellow
2 SG GND Black
1 VCC +5V White

References

  1. Geekhack — Hurricane Sandy Keyboard Sale Posted 2012-11-17. Retrieved 2024-04-21.
  2. ebay — Vintage NCR Workstation Keyboard K150V040 (Wayback Machine) Last updated 2018-01-27. Archived 2018-04-17.

External links