National WE-F451
This page was last modified 14:25, 10 July 2021 by Mars2000you.



The National WE-F451 is a CALL device that was used in many Japanese high schools to learn English. CALL is the abbreviation for Computer Assisted Language Learning.

It helps the students to practice English pronunciation by comparing their pronunciation with the "model" pronunciation. The system shows the result in a graphic display. The official name is "Speech Training Unit".

Besides the device, the package contains

  • the WE-F450 cartridge interface for connection to a MSX2 or MSX2+ computer
  • a National or Panasonic WE-5950 headset (headphone with microphone)
  • software for rhythm and intonation practice on the AS-202B floppy disk
  • two manuals, one about the unit, one about the software

The Speech Trainer could be used in a classroom with many computers + units connected to a console on the teacher's desk and the teacher was playing a tape recorder or speaking.

The unit includes analog-to-digital and digital-to-analog converters, and a speech-signal amplifier. The signal processing is done by the Z80A central processing unit of the computer.

Dials in front allow to adjust the volume of headset output and MIC/LINE input. Switches at the back allow to select the headset microphone or the line input, and to enable/disable the outputting of the headset microphone input signal to the line output (must be disabled when the unit is connected to teacher's console).

This product was not sold in shops or advertised in catalogs, as it was reserved for some schools.

Several optional software were available separately:

  • WE-AS201B - Creation of model voice for rhythm and intonation practice
  • WE-AS203A - Vowels practice
  • WE-AS204A - Hearing practice (creation)
  • WE-AS20SA - Hearing practice (quiz)


National WE-F451 with WE-F450
WE-F451 software manual
National WE-F451 back
National WE-F451 label on box
National WE-F451 floppy disk
WE-5950 headset
WE-5950 detail


  • Headset input connector
  • Line output connector (for PA system or a tape recorder)
  • Line output connector (for tape recorder)
  • Interface connector (with fixed cable)