DATAMATH CALCULATOR MUSEUM
Texas Instruments TI-2550 (1st design)
|Date of introduction:||January 10, 1974||Display technology:||LED-stick|
|New price:||$99.95, DM 298.00||Display size:||8|
|Size:|| 6.5" x 3.2" x
165 x 80 x 45 mm3
|Weight:||7.8 ounces, 220 grams||Serial No:||2550149705|
|Batteries:||3*AA NiCd or 4*AA Alkaline||Date of manufacture:||wk 29 year 1974|
|AC-Adapter:||AC9130 or AC9120||Origin of manufacture:||USA|
|Program steps:||Courtesy of:||Joerg Woerner|
|Download manual:||(US: 1.8M Bytes)|
year [or later - continue here] after the introduction of the famous
TI-2500 alias Datamath
the engineers at Texas Instruments added a full memory onto the calculator chip.
Integrated into a housing similar to the wedge shape of the SR-11
it was named TI-2550.
Today we know two different versions of the TI-2550:
The first calculators used a display module without magnification lenses (actually a Bowmar Opto-stick), later TI-2550 calculators got the bubble lenses known from the TI-1200 and TI-30.
A close relative of the TI-2550 was sold through the American department store Montgomery Ward. Compare the TI-2550 with the P200.
The same housing and a very similar keyboard was used by the TI-150.
Datamath™ is a trademark of Texas Instruments.
received from a fellow engineer of a Dallas based company a parcel with some
One of the surprises was a very early TI-2550 with a Date code on the calculator chip indicating end of June 1974 as manufacturing date. This prototype makes use of 9 single LED-modules known from the TI-2500 Version 3. Two explanations:
|• The TI-2550 was introduced later in 1974 as we assumed.
• This particular calculator was repaired and the first series
used the single LED-modules instead the Bowmar Opto-stick.
The TI-2550 is featured in the Texas Instruments
Deutschland GmbH leaflet
ER-1975 dated 1975.
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© Joerg Woerner, October 23, 2003. No reprints without written permission.