Texas Instruments TI-73 Explorer ViewScreen™

Date of introduction:  July 2006 Display technology:  LCD dot matrix
New price:  $150.00 (SRP 2008) Display size:  8 * 16 characters
Size:  7.2" x 3.2" x 0.95"
 182 x 81 x 24 mm3
Weight:  6.6 ounces, 186 grams Serial No:  2111000254
Batteries:  4*AAA + CR1620 (35mA) Date of manufacture:  mth 03 year 2007 (F)
AC-Adapter:   Origin of manufacture:  China (S)
Precision:  14 Integrated circuits:  ASIC: TI REF TI-738X
 Flash: 29LV400
 Display: Novatek NT7564H
Program steps:  25k Bytes, 128k Bytes Flash ROM Courtesy of:  Joerg Woerner

The TI-73 Explorer ViewScreen Calculator (VSC) is the teacher version of the standard TI-73 Explorer. It connects with a special port to a ViewScreen panel via a cable. Placing the panel on the overhead projector enlarges the image of the handheld screen so that each student can follow along.

Four ViewScreen panels were available in 2008:

Panel 1: TI-73 VSC, TI-73 Explorer VSC, TI-80 VSC, TI-82 VSC, TI-83 VSC,
   TI-83 Plus VSC, TI-83 Plus Silver Edition VSC, TI-84 Plus VSC,
   TI-84 Plus Silver Edition VSC
Panel 2: TI-89 VSC, TI-89 Titanium VSC, TI-92, TI-92 Plus, Voyage 200
Panel 3: TI-85 VSC (2nd design), TI-86 VSC
Panel 4: TI-Nspire, TI-Nspire CAS, TI-Nspire Touchpad, TI-Nspire CAS Touchpad

As an alternative the TI-Presenter video adapter connects to a TV or other projection device with a video input port. 

From a technical point of view the TI-73 Explorer VSC is almost identical with the students TI-73 Explorer. The main difference you notice is a bulgier bottom shell of the calculator housing to accommodate the ViewScreen electronics and connector.

Dismantling this TI-73 Explorer VSC with the Date code S-0307F manufactured in March 2007 by Inventec Corporation in Shanghai,China reveals a small printed circuit board (PCB) with two LVXC3245 driver chips connected with a flexible cable to the display PCB of the calculator.

Comparing this calculator with the original TI-73 VSC design reveals a lot of internal differences.

The original design of the TI-73 VSC made use of 5 main Integrated Circuits:

Zilog Z84C00 microprocessor
TI REF 9815455 ASIC
512k Bytes Flash ROM
32k Bytes Static RAM
Toshiba T6A04: Single-chip 64*120 pixel display driver

The new designed printed circuit board (PCB) needs just 3 Integrated Circuits:

ASIC: Z80 microprocessor, RAM and supporting logic
Macronix  29LV400 512k Bytes Flash ROM
Novatek NT7564H: Single-chip 64*120 pixel display driver

The picture on the right gives an enhanced view of the ASIC "TI REF TI-738X" that clocks the Z80 microprocessor with 6 MHz and incorporates the 32k Byte RAM and some supporting logic. Learn more about the Hardware Architecture of TI’s Graphing Calculators. The ASIC was probably manufactured by Toshiba and recalls us the TI-83 Plus Silver Edition with the "TI-REF 83PL2M/TA2" ASIC and the early TI-84 Plus with its "TI-REF 83PLUSB/TA2" ASIC. This ASIC "TI-REF TI-738X" was used in the revised TI-83 Plus, too.

Texas Instruments introduced with the original TI-73 already in March 1998 a groundbreaking architecture based Flash ROM technology to the students and this TI-73 Explorer ViewScreen calculator makes use of a Macronix MX29V400 chip with a capacity of 512k Bytes - about 128k Bytes of the device is available for the user.

The driver circuit of the LC-Display was traditionally manufactured by Toshiba for Texas Instruments' graphing calculators. This TI-73 Explorer VSC manufactured in March 2007 shows with the Novatek NT7564H a one-by-one replacement. It is just a bare chip mounted on a flexible piece of circuit board attached between the display and the main PCB.

A serial port of the calculators allows the connection to the Calculator-Based Laboratory system CBL, its successor CBL 2, the Calculator-Based Ranger CBR and its successor CBR 2.

Don't miss the colorful slide cases developed for the TI-83 Plus, they fit on the TI-73 ViewScreen, too.


TI-73_P0803G_OS.jpg (60011 Byte)1.90 (February 6, 2006)
1.91 (March 20, 2008, actual in February 2009) 

You can check the ROM version of your TI-73 Explorer using the following key sequence and reading the number on your screen:

[2nd] [MEM] [1]

Information provided by and Xavier Andréani.

Exam acceptance:

The TI-73 Explorer VSC is permitted (as of September 27, 2007) for use on SAT, ACT, PSAT and AP exams but is not recommended for the AP exam.

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If you have additions to the above article please email:

© Joerg Woerner, August 1, 2020. No reprints without written permission.