NCR 4950

NCR 4950

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.<ref>geekhack — Hurricane Sandy Keyboard Sale</ref> 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<ref>Archive.org - April 2018 Snapshot of eBay listing</ref>.

Gallery

White Hi-Tek switch version

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.

• 
  Top
• 
  Bezel removed, showing ADDS or AT configuration
• 
  Bezel removed, showing location of chart
• 
  Locations of connector
• 
  Locations of links for conversion
• 
  Locations of links for conversion #2
• 
  Hi-Tek switch and keycap

SKCL green version

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.

• 
  Top view
• 
  SKCL green
• 
  timestamp
• 
  Sticker inside

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

<ref>Deskthority - [1]</ref>

References

<references />