DATAMATH  CALCULATOR  MUSEUM

Texas Instruments Spelling B

Date of introduction:  1980 Display technology:  Fluorescent
New price:  $30.00 Display size:  8 alphanumeric
Size:  6.2" x 3.4" x 1.1"
 157 x 86 x 29 mm3
   
Weight:  5.7 ounces, 163 grams Serial No:  
Batteries:  9V  Date of manufacture:  wk 15 year 1980
AC-Adapter:   Origin of manufacture:  USA (ATA)
Precision:   Integrated circuits:  TMC0274, TMC0355 (CD2602)
Memories:      
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (EU: 6.6M Bytes)
  (EU: 3.9M Bytes)

About two years after the introduction of the original Spelling B appeared this slightly enhanced version. At first glance you'll notice the note symbol printed on the display bezel as a short hint to the added buzzer.

Dismantling this Spelling B manufactured in April 1980 by Texas Instruments in their Abilene, TX facility reveals a very clean design based on a double-sided printed circuit board (PCB) and powered by a 9V alkaline battery. Compared with the original design you'll notice the already mentioned additional piezo buzzer connected with two red wires to the PCB.

A closer inspection of the 2nd generation of the Spelling B reveals a big surprise!

The original design based on two TMS1000 series microcontrollers was replaced with a TMC0274 microcontroller and a TMC0355 Voice Synthesis Memory (VSM), known as " 128kBit Speech-ROM" of the Speak & Spell family.

An identical product was sold in United Kingdom with the Spelling ABC, while the Spelling ABC introduced in Germany makes use of another language ROM.

All models were later replaced with a product using a LC-display. View it here.



horizontal rule

If you have additions to the above article please email: joerg@datamath.org.

Joerg Woerner, June 6, 2008. No reprints without written permission.