DATAMATH  CALCULATOR  MUSEUM

Texas Instruments SR-56

Date of introduction:  May 21, 1976 Display technology:  LED-stick
New price:  $179.95, DM 598.00 Display size:  10 + 2
Size:  5.8" x 3.2" x 1.3"
 147 x 81 x 32 mm3
   
Weight:  8.5 ounces, 240 grams Serial No:  59452
Batteries:  BP1A Date of manufacture:  wk 49 year 1976
AC-Adapter:  AC9130A Origin of manufacture:  Italy (RCI)
Precision:  12/13 Integrated circuits:  TMC0501, TMC0537, TMC0538, TMC0599
Logic:  AOS - 7 Pending Operations, 9 () Displays:  DIS234G
Memories:  10    
Program steps:  100 Courtesy of:  Joerg Woerner
Download leaflet:   (US: 7.8M Bytes)
  (US: 3.5M Bytes)
Download manuals:   (US: 15.0M Bytes)
  (US: 13.1M Bytes)
  (US: 26.8M Bytes)

Texas Instruments formally introduced the SR-56 Programmable Calculator on May 21st, 1976 to fill the gap in its Portfolio of Scientific and Programmable Calculators:

SR-16-II:  Basic Scientific Calculator, Chain Logic
SR-50A: Scientific Calculator, Sum-of-Products Logic
SR-51A: Statistical Calculator, Sum-of-Products Logic
SR-56: Programmable Calculator, AOS
SR-52: High Programmable Calculator, AOS

The SR-56 not only shares the design with the SR-50A and SR-51A, even its internal construction is identical and the three calculators differ only in the population of the printed circuit board (PCB) used with all three designs:

Calculator Logic Arithmetic
Chip
SCOM
Chips
Multi-
Register Chip
Price
SR-50A (V2) SOP TMC0501 TMC0531   US$ 109.50
SR-51A (V2) SOP TMC0501 TMC0532
TMC0533
  US$ 224.95
SR-56 AOS TMC0501 TMC0537
TMC0538
TMC0599 US$ 179.95

The SR-50A and its sibling SR-51A were the result of a major redesign of the immaculate SR-50 design introduced already in January 1974 to reduce manufacturing costs but Texas Instruments hit during the redesign of the calculators a major roadblock with the TMC0530 Scanning Read-Only Memory (SCOM) Chip and introduced the first iteration of both the SR-50A and SR-51A with the TMC0520 SCOM Chips known from SR-50 and SR-51, respectively. When the SR-56 Programmable Calculator was finally launched with an Suggested Retail Price (SRP) of US$ 179.95, it was an immediate success and its price tag perfectly mirrored its capabilities compared to the SR-52:

Calculator Program
Steps
Memories External
Memory
Printer
Compatibilty
Price
SR-52 224 20 Integrated
Card Reader
PC-100,
PC-100A
US$ 395.00
SR-56 100 10 not available PC-100,
PC-100A
US$ 179.95

While the SR-56 Programmable works with both the PC-100 and PC-100A printer cradle, do the SR-50A (Version 2) and SR-51A (Version 2) not support an external printer.

Dismantling the featured SR-56 calculator with Date code 4976 RCI and manufactured in December 1976 in Rieti, Italy and comparing with an SR-50A (Version 1) calculator manufactured six months earlier in Italy reveals some unexpected changes. While the earlier calculator uses a SN97227 Clock Generator Chip in a small 8-pin DIP (Dual In-line Package with a 0.1” / 2.54 mm lead pitch) housing together with a TP4011A Clock Buffer Chip in a 14-pin DIP housing to reduce both real estate on the PCB and manufacturing costs compared to the original SR-50 introduced in January 1974, are these two Integrated Circuits (ICs) gone. And no, they are not hiding under the small power supply module on the right side of the PCB boosting the output of the rechargeable BP1A Battery Pack to the required voltages of the calculator electronics.

The secret sauce of the revised design is the new TMC0538 SCOM Chip replacing the TMC0521 Chip of the original SR-50A (Version 1) featuring an integrated Clock Generator for the TMC0501 Arithmetic Chip and the TMC0599 Multi-Register Chip used with the SR-56.

Other areas of the PCB didn't change that dramatically, we still identify the two SN27882 display drivers known from the previous designs of the calculator.

Comparing the PCBs of the three siblings SR-50A (Version 2), SR-51A (Version 2), and SR-56 (in TI internal documents often dubbed SR-51P for Programmable) reveals some very subtle differences, too. Right below the power supply module for the internal calculator voltages VDD (-10.0 Volts) and VGG (-15.8 Volts) you'll find a 50 and a 51 marking. Depending on the calculator model three configurations are populated:

SR-50A: A 150 kOhm resistor soldered into the left (50) position connects the CLK pin and VGG of the TMC0531 to enable its internal clock generator and providing the two
   non-overlapping clock signals with 180° phase difference and a frequency around 180 kHz to the TMC0501 Arithmetic Chip
SR-51A: A 150 kOhm resistor soldered into the right (51) position connects the CLK pin and VGG of the TMC0533 to enable its internal clock generator and providing the two
   non-overlapping clock signals with 180° phase difference and a frequency around 180 kHz to the TMC0501 Arithmetic Chip. The clock generator of the TMC0532 is disabled and it
   generates the D0 signal instead for possible PC-100 Printer Cradle compatibility
SR-56: A 30 kOhm soldered into the right (51) position connects the CLK pin and VGG of the TMC0538 to enable its internal clock generator, a 39 pF capacitor between the CLK pin
   and VSS greatly improves the stability of the clock frequency. The clock generator of the TMC0537 is disabled and it generates the D0 signal for PC-100 Printer Cradle compatibility

In the lower-left area of the PCBs you'll notice a small symbol for a diode but only the SR-56 has actually a diode soldered into the position, both the SR-50A and SR-51A are using a piece of wire, instead. From a technical point of view the diode is necessary for operation of the calculator on a PC-100 Printer Cradle. While the Key input matrix line KP of the TMC0501 Arithmetic Chip is used in stand-alone calculator mode for various keys (D1, D2, D3, D4, D6, D7, and D13), doubles it in the PC-100 Printer Cradle application to signal three additional conditions or actions:

D0: Presence detection of PC-100 Printer Cradle
D12: [PRINT] key detection
D15: [TRACE] switch detection

The SR-56 uses a second set of diodes and current limiting resistors for the charging circuitry of its battery pack to accommodate for the increased power consumption of the calculator due to the TMC0599 Multi-Register Chip compared to the SR-51.

Last but not least features only the SR-56 gold-plated contacts for the PC-100 Printer Cradle.

As of today we know two revisions of the consolidated PC used with the SR-50A (Version 2), SR-51A (Version 2) and SR-56 but noticed only one minor change in the "Clock Generator Patch Area". The unused wiring positions in the lower area of the PCB were removed to free up some space for the slightly larger power supply module. The picture on the right compares the relevant part of the PCB from two SR-51A calculators manufactured in April 1976 and November 1976.

There are two different external designs of the SR-56 known, one with and one without the word "Programmable" under the SR-56 logo. Comparing the internal design of the two SR-56 versions reveals no technical differences.

According to Texas Instruments the SR-56 was introduced May 21st, 1976 which corresponds to week 21 of the year. French collector Francis Martin was first reporting to the Datamath Calculator Museum that he discovered two SR-56 calculators with manufacturing Date codes of LTA 1176 and LTA 1276, a whooping 9 resp. 10 weeks before the date of the "official" introduction. Dismantling the calculators revealed Date codes of the two SCOM Chips of week 11, too for proof that the SR-56 were produced already in March and we assumed that Francis is the lucky owner of rare "pre-production run". We consequently started a Database with Serial Numbers and Date codes for SR-56 calculators and invited our fellow calculator aficionados to report their findings accordingly.

Next in line was Ken Kaplan reporting his SR-56 with Serial# 046479 and a production Date code LTA 0876 with SCOM Chips from week 5 before Lynn Shelley reported in March 2010 his SR-56 with Serial# 003594 and a production Date code 0476 DTA sporting SCOM Chips from weeks 02 and 03.

The discrepancy between SR-56 calculators manufactured as early as January 1976 and its "formal" introduction in May 1976 wasn't understood till we studied some notes from a former TI Quality Controls Engineer revealing that while the first member of the new TMC0530 SCOM Chip, the TMC0531 was up and running in March 1975 for a timely introduction of the SR-50A (Version 2), did the TMC0530 design not work properly and the rework of the Base Mask Design took more than 6 months. Texas Instruments consequently introduced an interims design for the SR-50A (Version 1) and SR-51A (Version 1) with the original TMC0520 SCOM Chips known from SR-50 and SR-51 and postponed the introduction of the SR-51P, later renamed to SR-56. Here at the Datamath Calculator Museum we label SR-56 calculators manufactured significantly before May 1976 as "SR-56 (Pre-Launch)" to study their differences (if any) to later SR-56 calculators.

Comparing the hardware of the SR-56 with its sibling SR-52, you'll notice some interesting differences:

Calculator Program
Steps
Memories SCOM
Chips
BROM
Chips
Multi-
Register Chips
SR-52 224 20 1 2 2
SR-56 100 10 2 0 1

While the SR-52 uses for its Instruction Memory a combination of one TMC0520 SCOM and two TMC0560 BROM Chips, is the SR-56 centered around two TMC0530 SCOM Chips. Utilizing two SCOM Chips obviously doubles the features provided by just one SCOM Chip as seen in the SR-50A or the SR-52 and we looked into the second SCOM Chip of the SR-56. According to the "Data Sheet" of the TMC0530, it provides four functionalities to calculators based on the TMS0500 Building Blocks:

KEYBOARD AND DISPLAY SCANNING: 16 Digit Times Output D0 to D15
INSTRUCTION MEMORY: Read-Only Memory (ROM) with 1,024*13 Bits for TMC0501/TMC0501E Arithmetic Chips
CONSTANT MEMORY: 16 Constants of up to 16 digits, each
DATA REGISTERS: 2 16-digit Data Registers for TMC0501/TMC0501E Arithmetic Chips

The TMC0560 BROM (Bare Read-Only Memory Chip provides just one functionality:

INSTRUCTION MEMORY: Read-Only Memory (ROM) with 1,024*13 Bits for TMC0501/TMC0501E Arithmetic Chips

And the TMC0599 Multi-Register Chip provides RAM (Random Access Memory) storing 240 program steps or 30 numbers of 16 digits, each and accessible through a 4-bit bidirectional I/O bus:

KEYCODE MEMORY: Up to 240 Program Steps for User Programs
DATA REGISTERS: Up to 30 16-digit Data Registers for TMC0501/TMC0501E Arithmetic Chips

Taking the different AOS Implementations with the SR-52 storing up to 10 pending operations and the SR-56 storing up to 7 pending operations into account, we have a good understanding of the Memory Partitioning of the two calculators:

SR-52:

3,096*13 Bits Instruction Memory in TMC0524, TMC0562 and TMC0563
224*8 Bits Keycode Memory in one TMC0599, leaving 2 Data Register available
20 16-digit Data Registers in the second TMC0599, leaving 10 Data Register available
2 16-digit Data Registers in TMC0524

SR-56:

2,048*13 Bits Instruction Memory in TMC0537 and TMC0538
100*8 Bits Keycode Memory in TMC0599, leaving 17 Data Register available
10 16-digit Data Registers in TMC0599, leaving 7 Data Register available
4 16-digit Data Registers in TMC0537 and TMC0538

The SR-52 uses up all but 14 and and the SR-56 all but 11 of their 16-digit Data Registers, exactly the difference in their AOS Implementations. None of the precious RAM left unused, leaving the final question about the extra Constant Memory available with the second TMC0538 used with the SR-56.

Comparing the Constant ROM Content with the programmed constants frequently used with computing algorithm of trigonometric functions like sine, cosine, or tangent of an SR-52 manufactured in April 1976 using the TMC0524 SCOM Chip with the TMC0537 SCOM Chip of the featured SR-56 with our TMS0500 Platform after recording their ROM Images showed as expected no differences. When we were looking into the constants programmed into the second SCOM Chip of an SR-51A (TMC0523A-5), we located as expected values like 2.54 (inches to centimeters), 0.3048 (feet to meters) and 0.9144 (yard to meters) used with its "Conversion Keys". But the SR-56 dropped these "Conversion Keys" in lieu of its blue "Special Function Keys".

We experienced a much bigger surprise when we were analyzing the Constant ROM Content of the TMC0538NL A7644 Chip and discovered Keycodes for these "Special Functions" of the SR-56 instead the Constants for the "Conversion Keys" of the SR-51A.

Analyzing the six programs totaling 127 program steps, we identified the routines for Polar/Rectangular Conversions [P→R], [R→P], Mean and Standard Deviation Calculation [Mean], [S.Dev.] and Data Entry [∑+], [∑−].

SR-56_Late_IC.jpg (247576 Byte)Texas Instruments introduced on May 24, 1977 the famous calculator trio TI-57, TI-58 and TI-59 replacing both the SR-52 and SR-56. German collector Stephan Feinen discovered recently a SR-56 with a production code of 2477 ACH - weeks after the introduction of the successors!

Don't miss a SR-56 manufactured in Brazil.



The SR-56 is featured in the Texas Instruments Incorporated bulletins CB-195A and SR-52_FL dated 1976 and in the Texas Instruments Deutschland GmbH leaflet ER-1976 dated 1976.

Fellow collectors - if you own a SR-56 please report us the serial number and date code on the back of the calculator for our SR-56 Database.

SR-56 Database

Serial Number Origin Date code Logo Owner
001202 USA ??? ??76   Enzo Messina
002030 USA ??? ??76   Dave Laffitte
003594 USA

DTA 0476

  Lynn Shelley
004257 USA DTA 0476   Scott Reynolds
004398 USA DTA 0476   Richard Berry
004403 USA DTA 0476   Joerg Woerner
004496 USA DTA 0476   Kirk B. Muri
006042 USA LTA 0676   Bill Kabelac
006468 USA LTA 0676   Bill Elliott
006902 USA LTA 0676   John Reichmann
007097 USA LTA 0676   Dr. Kevin Easley
007951 USA LTA 0876   Miroslav Krob
010946 USA LTA 1276   Paul Dadd
012794 USA LTA 0876   Luciano Bonfigli
012978 USA LTA 0876   Roberto Paoletti
014595 USA LTA 1276   Michael Klevickis
019040 USA LTA 1276   Carlos
019242 USA LTA 1276   Martin Ndzelen
021968 USA LTA 1276   Ivar Magnusson
026894 USA LTA 2476   Jayantilal M Patel
028275 USA LTA 0876   Joerg Woerner
028398 USA LTA 0876   Marie Lisa Collas
028531 USA LTA 0876   Coy Lam
028985 USA LTA 0876   Michael Mehlhorn
029118 USA LTA 0876   Osman Karaokcu
029747 USA LTA 0876   Marc-Eric Amstutz
029990 USA LTA 0876   Joerg Woerner
030952 USA LTA 4176   Bill Hastings
032022 USA LTA 0677   Skye Le
032431 USA LTA 4176   Kirk B. Muri
032705 USA LTA 4176   Palmer Hanson
035900 USA LTA 4176   Pat_man_pdo
037453 USA LTA 3876   James Doig
038477 USA LTA 1176   John M.
042489 USA LTA 0876   François Jacques
044120 USA LTA 0876   Giovanni Legnani
044311 USA LTA 0876   Kurt Pribil
044749 USA LTA 1176   Joăo Carlos do Rosário
045602 USA LTA 1176   Mike Parsons
046199 USA LTA 0876   Computer History Museum
046479 USA LTA 0876   Ken Kaplan
046644 USA LTA 0876   Clark Casale
048109 USA LTA 2076   Ken H. Meine
051730 USA LTA 2076   Ben Davis
053142 USA LTA 3076   Joerg Woerner
055273 USA LTA 3076   Wolfgang Kemper
055673 USA LTA 3076   Maite Urrutia
056731 USA LTA 2076   Jack Crafchick
056955 USA LTA 2076   Gabriel Baum
060538 USA LTA 1276   R.J. Legman
060685 USA LTA 1276   John Versluys
061649 USA LTA 1276   Ray Foulkrod
062625 USA LTA 1276   Joerg Woerner
065865 USA LTA 1276   George Nix
066174 USA LTA 1276   Kirk B. Muri
066311 USA LTA 1276   Hans-Peter Bieger
067219 USA LTA 4176   Al Paslow
069417 USA LTA 3276   Joerg Woerner
072261 USA LTA 3276   Kirk B. Muri
079905 USA LTA 2476   Jack Crafchick
080968 USA LTA 3076   Alain Gressier
083257 USA LTA 3076   Leo Wilkie
083301 USA LTA 3076   Joerg Woerner
088033 USA LTA 3076   Claus Buchholz
088661 USA LTA 3076   Dave
090418 USA LTA 3776   Walter Roberson
093896 USA LTA 3776   Edward Boyles
094013 USA LTA 3176   Hugh Wilkinson
094606 USA LTA 3176   BillPeacher
095464 USA LTA 3276   Kirk B. Muri
095984 USA LTA 3276   Randall Scheuerman
096720 USA LTA 3676   Kirk B. Muri
098184 USA LTA 3676   Glen Petersen
098537 USA LTA 3676   Computer History Museum
102519 USA LTA 3776 Programmable Bob Tessier
103493 USA LTA 3976   Lenny Tosto
103998 USA LTA 3976   David Balcaen
108461 USA LTA 3176   Stephanie Huang
109527 USA LTA 3276   Jim Murphy
112881 USA LTA 3576   Guenther Engelhart
113960 USA LTA 3576   Michael Young
114101 USA LTA 3576   Michael Shackelford
118534 USA LTA 3676   Paul Kowalski
118713 USA LTA 3676   Joerg Woerner
118822 USA LTA 3676   Gavin Wickham
121400 USA LTA 3276 Programmable Joerg Woerner
123276 USA LTA 4676   Ernest Orr
123480 USA LTA 4676   Joy Eberhardt
123831 USA LTA 3176   Mark Sherman
130278 USA LTA 5176   Ken H. Meine
130956 USA LTA 5176   Henry Gleizer
131439 USA LTA 5176   Marie Lisa Collas
131819 USA LTA 5176   Al Paslow
132929 USA LTA 4976   Vasiliy Tolstoy
134128 USA LTA 4976   Mario Cusenza
135621 USA LTA 0477   Javier Juncadella
137931 USA LTA 4776 Programmable Miroslav Krob
______ USA LTA 0577 Programmable Joerg Woerner
145936 USA LTA 4876   Victor Rollinger
146169 USA LTA 4876   n.a.
146241 USA LTA 4976   Joerg Woerner
146278 USA LTA 4976   Miroslav Krob
146512 USA LTA 4976   Uwe Stöcks
146619 USA LTA 4976   D. van der Neut
151773 USA LTA 0877 Programmable Kirk B. Muri
152051 USA LTA 0877 Programmable Joerg Woerner
154031 USA LTA 4576   S.Plavinski
154601 USA LTA 4676   Erik Polk
154605 USA LTA 4676   Roger Ogé
154880 USA LTA 4676 Programmable John Lambert
155114 USA LTA 4676   Marko Sokolich
156054 USA LTA 4876   Brian White
163274 USA LTA 0277 Programmable Jack Hummingbird
163654 USA LTA 0377 Programmable Klaus Boehm
164416 USA LTA 0277 Programmable Ken H. Meine
166016 USA LTA 0277 Programmable Don
167288 USA LTA 0377 Programmable Eric Schwarz
169517 USA LTA 0577 Programmable Dr Steve Weddell
170452 USA LTA 0577 Programmable Joerg Woerner
172394 USA LTA 5176   Kirk B. Muri
173341 USA LTA 5176   Dr. Gar Won Ko
173990 USA LTA 5176   Jake Gowans
176799 USA LTA 0677   Enrique Garcia Ortiz
177154 USA LTA 0677   David Ribera
177390 USA LTA 0677   Zbynek Hak
177787 USA LTA 0677   Thomas Kapper
182052 USA LTA 0677 Programmable Greg Kulp
182131 USA LTA 0677 Programmable William Ramsey
182550 USA LTA 0677 Programmable Sid Ellis
183757 USA LTA 0377 Programmable Kirk B. Muri
188872 USA LTA 0477 Programmable Joerg Woerner
190055 USA LTA 0277   Joerg Woerner
191052 USA LTA 0477 Programmable Dr. Jürgen Rodenkirchen
191156 USA LTA 0477   Lynda Charles Shelton
191372 USA LTA 0477   bennyboy6
193158 USA LTA 0477   Mark E. Berger
2497970 USA LTA 1577   John Jones
2498363 USA LTA 1577 Programmable Harry Shaw
2499159 USA LTA 1677   José López
3101291 USA LTA 1077   Bruce Kernes
          
051742 Brazil 5076 CIB    Joerg Woerner
054273 Brazil 1877 CIB    André Luis Trentin
054399 Brazil 2177 CIB    Roberlei Gentil Toniete
055816 Brazil ____ CIB    Romildo P. Módolo
          
9101370 Netherlands 1676 ACH   Erich Schikuta
9102216 Netherlands xxxx ACH   Luis Ametrans
9102853 Netherlands 1676 ACH   Alex Guerrazzi
9103424 Netherlands 1476 ACH   Gilbert Leray
9103776 Netherlands 1476 ACH   Tihomir Santek
9103817 Netherlands 1476 ACH   Matthias Hofer
9105502 Netherlands 3976 ACH   Karol Orlowski
9106757 Netherlands 1177 ACH   Maciej Wirkus
9107471 Netherlands 1976 ACH   Henrique Martins
9107752 Netherlands 0577 ACH   John Warman
9108417 Netherlands 2376 ACH   Rudolf Lovnički
9108764 Netherlands 2276 ACH   Juan Jose Romera
9108918 Netherlands 2376 ACH   Leen Boers
9108935 Netherlands 2376 ACH   Jeroen Gietema
9109964 Netherlands 1876 ACH   José Levon
9110392 Netherlands 2376 ACH   Rafael Sevilla
9111014 Netherlands 2276 ACH   Leo van Hoeken
9111387 Netherlands 2376 ACH   Josef Bém
9113462 Netherlands 2376 ACH   Erik Remander
9114429 Netherlands 2476 ACH   John Fletcher
9114697 Netherlands 2276 ACH   Gordon Johnston
9115309 Netherlands 2476 ACH   Bob Worsley
9116613 Netherlands 4776 ACH   Doug
9116904 Netherlands 4876 ACH   Rudi Verdoodt
9117455 Netherlands 4876 ACH   Joerg Woerner
9119154 Netherlands 4376 ACH   Lars Olejnik
9119233 Netherlands 4376 ACH   Sture Bloom
9119742 Netherlands 4376 ACH   Joerg Woerner
9120647 Netherlands 4876 ACH   Joerg Woerner
9121717 Netherlands 3477 ACH   Pierre Morisset
9121832 Netherlands 0377 ACH   Richard Kaye
9122526 Netherlands 5276 ACH   Joăo Carlos do Rosário
9122910 Netherlands 0177 ACH   Stuart of Blyth
9123166 Netherlands 4876 ACH   Thomas Ritschel
9126020 Netherlands 3477 ACH   Joerg Woerner
9126481 Netherlands 0477 ACH   Paul Hofbauer
9127791 Netherlands 0277 ACH   Giovanni Bellini
9______ Netherlands 1277 ACH   Hans Larson
9______ Netherlands 1377 ACH   Marie Lisa Collas
9______ Netherlands 1777 ACH   Erich A. Gindl
9______ Netherlands 1977 ACH   Kurt Pribil
9______ Netherlands 2377 ACH   Allan W B Stalker
9______ Netherlands 2477 ACH   André Wilhelmus
9136908 Netherlands 1977 ACH   Owen Savill
9138504 Netherlands 2477 ACH   Michael Behnsen
9143748 Netherlands 1877 ACH   Zbynek Hak
9145454 Netherlands 1877 ACH   Thomas Gill
9147826 Netherlands 2277 ACH   Tom Pereira
91486xx Netherlands 1277 ACH   Miroslav Krob
9153225 Netherlands 1377 ACH   Aron Barman
9154314 Netherlands 1577 ACH   Tiny Henst
9154587 Netherlands 1577 ACH   John Dale
9159914 Netherlands 1277 ACH   Thomas Gill
9______ Netherlands 2177 ACH   Marie Lisa Collas
9______ Netherlands 2477 ACH   Stephan Feinen
9______ Netherlands 2477 ACH   Marc van Lemmen
9______ Netherlands 2477 ACH   Christoph Kraft
9194747 Netherlands 2477 ACH   Ignacio Sánchez Reig
          
07287 Italy 1377 RCI   Joăo Ferreira do Rosário
10693 Italy 3876 RCI   Erik Waelchli
12140 Italy 3876 RCI   Thomas Fänge
13035 Italy 3276 RCI   Marcus von Cube
13062 Italy 3276 RCI   Lars Herold
13525 Italy 3276 RCI   Dieter Teuchert
13757 Italy 3276 RCI   Joerg Woerner
A12385 Italy 3176 RCI   Stephan van Radecke
A14708 Italy 3276 RCI   Leonardo Galeone
A15103 Italy 3676 RCI   Thorsten Gruschke
A16658 Italy ____ RCI   Tsjip de Leeuwentemmer
A17711 Italy 3276 RCI   Marie Lsia Collas
18150 Italy 4276 RCI   Zbynek Hak
19477 Italy 4076 RCI   Joerg Woerner
19818 Italy 4276 RCI   M. Door
19934 Italy 4276 RCI   isidoro
20485 Italy 1377 RCI   Tibor Cinkler
21480 Italy 4076 RCI   Monkey Nut
21502 Italy 4176 RCI   Bruno Studer
_____ Italy 4276 RCI   Varga Balázs
34793 Italy 4876 RCI   Enrico Vidale
34860 Italy 4976 RCI   Maximilian Hauser
35794 Italy 4976 RCI   Audun Mathisen
50861 Italy 4976 RCI   Iztok Robic
51377 Italy 4176 RCI   Miroslav Krob
51733 Italy 4976 RCI   Francis Massen
51717 Italy 4976 RCI   Michel Lahcem
51847 Italy 4976 RCI   Peter Engels
53206 Italy 4976 RCI   Dina Marian
53938 Italy 4976 RCI   Joerg Woerner
54020 Italy 4976 RCI   Joerg Woerner
54135 Italy 4976 RCI   Thomas Kapper
55196 Italy 4976 RCI   Marie Lisa Collas
55438 Italy 4976 RCI   Fedele Decandia
55527 Italy 4976 RCI   Jřrn Skoven Pedersen
57237 Italy 4976 RCI   Pierre Houbert
57913 Italy 4976 RCI   Bastian Schmelzer
59452 Italy 4976 RCI   Joerg Woerner
59728 Italy 4976 RCI   Ian Stirling
60300 Italy 4976 RCI   Juri Schauder
16949 Italy 0577 RCI  Programmable John Dale
20944 Italy 0577 RCI  Programmable Christoph Oertli
22102 Italy 1277 RCI  Programmable Angelo Elifani
30142 Italy 0577 RCI  Programmable Paul Debono
          

 

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

© Joerg Woerner, December 5, 2001. No reprints without written permission.