Electronic Desktops Page

Last Update: January 22, 2003 -- THE CALCULATOR REFERENCE


1 Burroughs C3260 -- C-031992-101
This is one of my favorite desktops due to it's unique itron display. The itron tube uses eight segments to display it's numbers. The numbers are more curved than a seven-segment style display. They almost look handwritten. The "0" is the size of a lower case "o". The keyboard has 5 strange function keys, a divide/multiply key, a +/= key, an equal key with a dot above and below it -- it looks like a divide symbol with a double center line, a diamond key, and a plus key. Go figure!
8 digit plus sign -- vacuum fluorescent tubes (itron)
17 key keyboard
Four function plus memory
2 position Memory switch (MEM , 16)
2 position Clear memory momentary slide switch (CM)
6.2" wide x 3.5" high x 10.0" deep
Fixed line cord

2 Casio AS-L -- B 710214
The Casio is an unique desktop due to it's wide aspect ratio. The unit uses tiny nixie tube displays that are to the left of the keyboard.
12 digit plus sign -- nixie tubes
19 key reed switch keyboard
Four function plus memory
6 position Decimal slide switch (5 , 4 , 3 , 2 , 1 , 0)
3 position 5/4 slide switch (F , 5/4 , CUT)
13.3" wide x 3.5" high x 5.4" deep
Removable line cord

3 Commodore C108 -- L-65066 121
The C108 is in a sharp looking black case. This model uses individual 7-segment display tubes for it's display. It's keyboard is very simple with the + and - buttons including the ='s as well ("- =" & "+ =").
8 digit plus sign -- vacuum fluorescent tubes
17 key reed switch keyboard
Four function
6.8" wide x 2.5" high x 8.9" deep
Fixed line cord

4 Commodore C8 -- ELF3-05 - 019727
The C8 is a sharp unit in it's black case with bright glossy keys. It has a cool gas plasma display that glows orange due to it's neon gas.
9 digit -- 7-segment gas plasma panel
18 key keyboard
Four function plus constant
6.7" wide x 2.4" high x 9.0" deep
Fixed line cord

5 Compucorp 322G Scientist -- 4205472
The Compucorp units were scientific calculators that were ahead of their time. Their insides were packed with stacked circuit boards with many large 40 pin LSI chips all made by TI.
16 digit -- Burroughs Panaplex II BR16252 Gas Plasma Panel
42 key keyboard
Scientific plus memory and pi
2 position GRAD/DEG slide switch
5.4" wide x 2.8" high x 9.0" deep
Removable AC adapter or 4 "C" batteries

6 Compucorp 324G Scientist -- 5300909
This unit was a scientific programmable. Actually many of these models, including the 322G above were programmable. Compucorp simply removed the key tops and covered the programming keys with a keyboard overlay! In college we used to remove the keyboard overlays in order to access the more advanced (and expensive) functions.
16 digit -- Burroughs Panaplex II BR16252 Gas Plasma Panel
43 key keyboard
Scientific programmable plus memory and pi
2 position GRAD/DEG slide switch
2 position PROG1/PROG2 slide switch
2 position RUN/LOAD slide switch
5.4" wide x 2.8" high x 9.0" deep
Removable AC adapter or 4 "C" batteries

7 Denon DEC-521 -- 200421
This is a classic old nixie tube based unit with small scale integrated circuit logic and a ton of diodes.
12 digit plus sign -- nixie tubes
25 key reed switch keyboard
Four function plus memory and Constant
2 position T switch
2 position Constant switch
2 position 5/4 switch
10 position Decimal rotary switch (0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9)
10.4" wide x 4.0 " high x 13.0" deep
Removable line cord

8 Denon DEC-621 -- 0504390
This Denon, like the 521, is also a classic nixie tube unit. The circuitry is discrete enough to require a horizontal mother board with 7 vertical logic cards. I took this unit apart only to find that when I reassembled it that it was dead. This horrible event rarely happens to me so I knew there must be a reason (I'm always careful to use static procedures). I finally discovered the problem was the unit was so old that the connectors contacts had lost their springing function. I spent the next few hours carefully stuffing 1/32" strips of the pink polly foam behind each of the connector contacts (many hundred). The good news was the foam restored the connectors spring and the unit worked!
14 digit plus sign -- nixie tubes
24 key reed switch keyboard
Four function plus memory and Constant
2 position T switch
2 position Constant switch
4 position Decimal Function rotary switch (F , D , 5/4 , R)
4 position Decimal rotary switch (0 , 2 , 3 , 6)
11.3" wide x 4.1" high x 15.3" deep
Removable line cord

9 HP Model 46 -- 1314A00313
One of two large desktops that HP made. They were housed in a cast aluminum case and used a printer mechanism made by Shinshu Seiki Co. Ltd.. The printer was unique in that it housed a spinning drum behind the paper. On the drum were all of the numbers and letters required for each column. In front of the paper was the ribbon and then a row of hammers. The hammers would fire towards the paper just when the desired character was spinning by the back of the paper. The hammer would strike the ribbon pushing it into the paper and making an imprint of the character on the drum on the paper! When the printer was de-selected (display only) it would eventually power down and stop spinning the drum.

On dumb thing HP did was make the LED display an option. The only cost this saved was with the LED arrays. The LED driver chips, just like in the Classic series, were still populated on the display card because these chips were required to generate the two phase system clocks.
No display -- LED
41 key keyboard
Scientific plus memory
2 position Printer switch (On , Off)
18 column impact printer identical to Monroe 1330-1 printer
10.8" wide x 4.2" high x 15.4" deep
Removable line cord

10 MITS 816B -- 1629
Yes, this puppy was my first calculator. I built it from a kit in high school. I had to save for months for this kit by working in a hardware store assembling bikes and toys. In January of 1972 I purchased this unit for $184.00 including $5.00 for shipping, handling, and insurance. I "leased" it to my teachers my senior year for a higher grade! They in turn used it to average their grades! The unique thing the MITs did was display 16 digits of precision, eight digits at a time. There was a shift key that would flip the two banks of digits.
9 digit -- vacuum fluorescent tubes
20 key keyboard
Four function
2 position Constant switch
8.5" wide x 4.1" high x 12.7" deep
Fixed line cord

11 Monroe 1330-1 -- M212314
I picked this beast up at a great price. Even though it was large what attracted me was its small LED display. The display used digits about the size of those used in the HP Classic series. I was also surprised to find that it used the same printer that was used in the HP 46 and 81 models.
15 digit -- LED (~HP-35 style and size)
26 key keyboard
Four function plus memory and constant
11 position Decimal slide switch (+ , F , 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8)
2 position 5/4 switch (v , 5/4)
2 position math switch (x= , =/)
3 position Printer switch (Disp , Printer , GT)
18 column impact printer identical to HP-46 printer
11.0" wide x 4.6" high x 14.5" deep
Removable line cord

12 Monroe 2020 -- P882615
This guy came along for the ride when I bought a lot of calculators at a local state university surplus auction.
12 digits plus sign -- vacuum fluorescent panel
32 key keyboard
Four function plus memory, %, %Delta, Tax, Avg, #/Date
7 position decimal slide switch (+ , F , 0 , 2 , 3 , 4 , 6)
3 position 5/4 slide switch (^ , 5/4 , v)
2 position slide switch (. , GT)
2 position slide switch (D , PD)
18 column printer
8.2" wide x 2.9" high x 10.9" deep
Removable line cord

13 Panasonic -- Je-1801P
This unit is too large to be a handheld and too small to be a desktop.
10 digit plus sign -- vacuum fluorescent module
29 key keyboard
Four function plus memory and %
5 position Decimal slide switch (F , 0 , 2 , 3 , A)
2 position Printer slide switch (P/D , D)
2 position 5/4 slide switch (v , 5/4)
2 position IP slide switch (. , IP)
13 column Printer
4.4" wide x 2.3" high x 9.0" deep
Removable AC adapter

14 R/S EC-3007 (65-664A) -- DT 129469
A freebie. I don't throw out anything.
10 digit plus sign -- vacuum fluorescent module
31 key keyboard
Four function plus memory and %
3 position Decimal slide switch (F , 4 , ADD)
2 position 5/4 switch (5/4 , .)
2 position Printer slide switch (. , NP)
15 column Printer
7.7" wide x 2.3" high x 9.3" deep
Fixed line cord

15 Ricoh Ricomac 1217 -- 7551-80 R-11043
The Ricoh has internal batteries and a small charge meter on the upper right side of the case. 7-segment fluorescent tubes glow a bright green.
12 digits plus sign -- Vacuum Fluorescent tubes
25 key keyboard
Four function plus memory and %
2 position 5/4 switch (v , 5/4)
7 position Decimal slide switch (F , 0 , 1 , 2 , 3 , 4 , 6)
7.7" wide x 2.7" high x 9.6" deep
Removable line cord

16 Sears 12 -- 728-58050 100193
The Sears unit has a gas plasma display and glossy keyboard just like the Commodore C-8. I'll bet I know who made this unit for Sears!
12 digit plus sign -- gas plasma panel
22 key keyboard
Four function plus memory and constant
4 position Decimal slide switch (4 , 3 , 2 , F)
6.7" wide x 2.4" high x 8.9" deep
Fixed line cord

17 Sharp ELSI-803 -- 29783109
An interesting wedge shaped case like the 804.
9 digit -- vacuum fluorescent tubes
17 key keyboard
Four function
2 position Constant slide switch (K , N)
9.1" wide x 2.9" high x 7.6" deep
Fixed line cord

18 Sharp ELSI-804 -- 3020075
An interesting wedge shaped case like the 803.
9 digit -- vacuum fluorescent tubes
17 key keyboard
Four function
2 position Constant slide switch (K , N)
7.2" wide x 2.9" high x 8.8" deep
Fixed line cord

19 Sharp EL-1197S -- 38113539
This unit is another one of those state university auction tag-alongs.
10 digit plus sign -- vacuum fluorescent module
24 key keyboard
Four function plus memory and %
2 position Printer slide switch (On , Off)
3 position Constant switch (K , . , A)
4 position Decimal slide switch (F , 3 , 2 , 0)
12 column Printer
7.8" wide x 2.9" high x 10.3" deep
Fixed line cord

20 Sharp ZL-6100S -- 5900068Y
This unit was a real interesting find. Though it was huge and had a printer, I was attracted to the unique 5x7 dot matrix alphanumeric vacuum fluorescent display. The keyboard also includes a digit backspace key like that used on later HP models. I often wonder why all calculators don't include a digit backspace since they're so much easier to use opposed to pressing "CE".

The printer is a compact dot-matrix design.

I was surprised and delighted to find that the unit uses a Z80 microprocessor for it's CPU engine. It also allows an optional ROM cartridge (COMPET custom program cartridge) to be plugged into the top of the unit through a magnetic access door. The ROM cartridge plugged into mine had a series of saving and loan amortization programs programmed into it (Mortgage Package 1). This baby was probably some expensive machine in it's time.
20 digit -- 5x7 dot matrix vacuum fluorescent panel (alphanumeric)
39 key keyboard with 10 function keys w/ LEDs
Digit backspace entry key (like on later HPs)
Four function plus memory and constant and %
8 position Decimal slide switch (F , 8 , 6 , 4 , 3 , 2 , 1 , 0)
5 position Mode slide switch (5 , 4 , 3 , 2 , 1)
2 position Printer switch (Off , On)
3 position 5/4 slide switch (^ , 5/4 , v)
3 position Constant slide switch (K , . , A)
22 column dot matrix printer (alphanumeric)
11.3" wide x 4.6" high x 14.6" deep
Fixed line cord

21 Sharp CS-224V -- 27064509
This is a sleek little unit with a Burroughs Panaplex display. It has a strange raised toggle switch with a center resting position. The switch can be toggled momentarily up or down to two labels. . . "VM IN" and "VM OUT". What are these????
12 digits plus sign -- Burroughs Panaplex BR13401 Gas Plasma Panel
23 key reed switch keyboard
Four function plus memory and constant
VM IN/VM OUT toggle switch
7 position Decimal slide switch (0 , 1 , 2 , 3 , 4 , 6 , 11)
2 position 5/4 switch (v , 5/4)
8.8" wide x 3.5" high x 11.1" deep
Removable line cord

22 Tempest DC-I-600 -- 490636
The Tempest was described by a friend as "Star Trekie". It's hard to describe but it's something like a rectangular saucer shape. It's has a wide keyboard area that's shaped something like a duck bill. Inside the display uses individual and extremely rare 7-segment gas plasma tubes.
9 digit -- gas plasma tubes
18 key keyboard
Four function plus constant
2 position Constant slide switch (K , Off)
5 position Decimal slide switch (F , 2 , 3 , 4 , 5)
6.7" wide x 2.6" high x 9.9" deep
Fixed line cord

23 TI-5030 -- 084 T 927224
Another TI in another bargain.
10 digit plus sign -- vacuum fluorescent module
27 key keyboard
Four function plus memory and %
2 position Printer slide switch (On , Off)
5 position Decimal slide switch (+ , F , 0 , 2 , 4)
10 column Printer ??
7.3" wide x 1.6" high x 8.0" deep
Removable AC adapter

24 TI-5040 -- 1332567 ATA1181
1380847 ATA1681
One of the most popular TI desktops. I have two because once again I got them cheap.
10 digit -- vacuum fluorescent module
27 key keyboard
Four function plus memory
2 position Decimal slide switch (F , A)
12 column Thermal Printer
9.2" wide x 3.0" high x 9.4" deep
Fixed line cord

25 TI-5100 -- 7700099 MTA4177
Another popular TI desktop that uses an AC adaptor (wall wart) power source.
10 digit plus sign -- vacuum fluorescent panel
22 key keyboard
Four function plus memory, constant, and %
2 position Decimal slide switch (F , 2)
2 position Constant slide switch (K , C)
7.6" wide x 2.5" high x 7.8" deep
Removable AC adapter

26 TI-5130 -- 357343
A common later desktop that I picked up for the right price! It has a huge toggle power switch. It also has a digit backspace key like on later HPs.
10 digit plus sign -- vacuum fluorescent panel
28 key keyboard
Four function plus memory and %
2 position Printer slide switch (Off , On)
2 position 5/4 slide switch (Off , On)
6 position Decimal slide switch (+ , F , 0 , 2 , 3 , 4)
12 column printer
8.2" wide x 2.2" high x 9.4" deep
Fixed line cord

27 TI-5130 II -- 430481 Z-1089B
Another later common TI, another good price! The display is recessed back on the right hand side.
12 digit plus sign -- vacuum fluorescent panel
30 key keyboard
Four function plus memory and %
3 position Printer slide switch (Off , On , IC)
2 position 5/4 slide switch (Off , On)
6 position Decimal slide switch (+ , F , 0 , 2 , 3 , 4)
12 column printer
9.5" wide x 2.7" high x 9.8" deep
Fixed line cord

28 TI-5310 -- 259667
Another TI, another good price. This model was cool because of it's financial function. It even included a top compartment that holds a Quick Reference Guide.
12 digit plus sign -- vacuum fluorescent panel
38 key keyboard
Four function plus memory, %, and Financial functions
2 position Printer switch
2 position 5/4 slide switch (v , 5/4)
3 position Sigma/Off/Margin slide switch
6 position decimal slide switch (+ , F , 0 , 2 , 3 , 4)
18 column printer
9.0" wide x 2.4" high x 11.3" deep
Fixed line cord

29 Underwood 400aPD -- 6469735
An old unit with a very colorful keyboard.
13 digit -- vacuum fluorescent tubes
25 key keyboard
Four function plus %
2 position Print slide switch (Off , On)
2 position slide switch (Off , ACC)
3 position R/O slide switch (0 , 5 , 9)
8 position Decimal slide switch (+ , 0 , 2 , 3 , 4 , 5 , 6 , FL)
10.9" wide x 3.8" high x 9.3" deep
Removable line cord

30 Victor 180-- 19-1721 #4710-115
I found an ad for this calculator in an April 1973 Scientific American. I knew upon seeing the ad that I wanted to find one of these units. This is one of my most recent finds.
14 digit -- Burroughs Panaplex BR16401 Gas Plasma Panel
32 key keyboard
Scientific plus memory and pi
2 position Degree/Radian slide switch
2 position Common/Natural Log slide switch
10.0" wide x 5.0" high x 11.5" deep
Removable line cord


The Calculator Reference by Rick Furr (rfurr@vcalc.net)
Back to The Calculator Reference