DATAMATH CALCULATOR MUSEUM
Montgomery Ward P8M aka TXI-8646A
|Date of introduction:||August 20, 1973||Display technology:||LED-modules + lens|
|New price:||$99.50||Display size:||8|
|Size:|| 5.7" x 3.1" x 1.6"
146 x 79 x 41 mm3
|Weight:||5.1 ounces, 144 grams||Serial No:||47F-0023467|
|Batteries:||4*AA||Date of manufacture:||wk 20 year 1974|
|AC-Adapter:||Origin of manufacture:||USA|
|Precision:||Integrated circuits:||WD LC1552B|
|Program steps:||Courtesy of:||David Smith|
This neat calculator does not look like a Texas Instruments product. To identify it, you have to know more about the coding used by Montgomery Ward:
Models starting with
• TXI were produced by Texas Instruments
• DAN were produced by APF
• DNS were produced by National Semiconductors (later Novus)
• GLE by Lloyd's
If you remember the famous Texas Instruments Datamath (TI-2500) and add a 4-key memory you would get a similar calculator to this wonderful find. There are only few calculators reported which have no direct counterpart of existing TI-products. With the P8F alias TXI-8644A and the P8P alias TXI-8645A two similar calculator without memory were sold, too.
dismantle this calculator, one question will arise immediately:
Was this calculator really manufactured by Texas Instruments?
The integrated circuit inside is not manufactured by Texas Instruments and one step ahead the TI chips of that era. The TI-2550 with similar complexity (%-key and 4-key memory) was introduced almost 6 month later. Maybe TI had a delay in the development of the TMS0601, the direct counterpart of the Western Digital LC1552 used with this P8M.
The keyboard of the calculator is a mixture of the TI-1500 keys and the grid of the Datamath. The display board was manufactured by Texas Instruments, too. And we could proof easily: This cutie IS a Texas Instruments calculator. The answer is found in the magic number 13-04-709-478 on the printed circuit board. Read more here. With the Radio Shack EC-300 Texas Instruments used the LC1552 a second time.
Don't miss the rare TXI-8661A based on the Exactra 23 calculator.
Datamath™ is a trademark
of Texas Instruments.
If you have additions to the above article please email: email@example.com.
© Joerg Woerner, December 5, 2001. No reprints without written permission.