Third Generation
Overview
The external appearance of the NMB third generation more resembles the IBM Model M with a similar wedge shape case. The third generation is a 101 key layout.
The Third generation has an AT/XT switch that can be accessed through the bottom case and protocol selection is marked with a sticker. Molded feet are flush when collapsed into the back of the lower case. When extended they raise the back of the keyboard slightly. Four rubber feet help the keyboard from moving.
The third generation of NMB Hi-Tek 725 series keyboards have the following seven main components introduced:
Switches
Keycaps
Upper Case
Mounting Plate
PCB
Back Plate
Cable
Switches
Keycaps
The keycaps are made out of PBT with dye-sublimated legends. The keycaps for the third generation include clips on the sides of the keycaps to secure them properly to the switch.
The keycaps on generation three boards contain rod stabs similar to IBM and Alps stab rods.
This generation introduced is the IBM sublegends on the number pad of this generation of keyboards. Later on in the generation, the keycaps changed the side of keycaps from smooth to rough plastic.
Upper Case
The upper case is made out of a single piece of beige ABS plastic. The plastic is textured due to the molding process that is used to create the upper case.
Lower Case
The lower case is molded from the same ABS plastic as the upper case. A set of slots are located in the lower case that joins the two halves together. The feet that are integrated into the lower case are flush with the lower case when retracted.
Switch Plate
The switch plate is made out of stamped steel. The plate is bent on either so that it can be mounted to the upper case. The plate is painted with a thin layer of black paint. The paint is then protected by a thin layer of oil to prevent rust.
PCB
The PCB is a double-sided PCB with all traces on the backside of the PCB. Some of these keyboards contain diodes which enables the keyboard to have n-key rollover.
Cable
The cable is approximately 1 meter long for the coiled variant and stretches up to 2 meters easily. It contains a molded 5 pin din connector with 6 pin headers using a molex connector on the PCB.
Variants
Top
PCB
Cable
Cable
Back
Switches
PCB