Friday, January 13, 2017

Retro Review: Sharp Compet CS-2302 Review

Retro Review:  Sharp Compet CS-2302 Review

I’m going for a little departure from the usual types of calculators I cover.

Sharp Compet CS-2302

Company:  Sharp
Type:  Adding Machine, Paperless
Years Made: 1970s
Batteries:  AC Plug

I purchased the Compet CS-2302 from a local thrift store in Glendora, CA back in the summer of 2016. 

Adding machine, but where’s the tape?

The CS-2302 is a paperless desktop calculator, but retains the characteristics of an adding machine.  That is to add numbers, enter your number and press [ + = ].  The total is immediately displayed.  Same with subtraction, press [ - = ] to subtract. 

What is unusual about the CS-2302 is a lack of a subtotal or total key (normally marked [ S ] and [ * T ], respectively).  Totals are cleared by pressing the clear button twice.

There is an exchange key [ ↕ ] on the CS-2302, something I don’t ever recall seeing on an adding machine.

The CS-2302 has two memories, M and I.  There are separate memory add and recall keys dedicated to both memories.

The keyboard is very solid.  The keys are responsive and it was well maintained. 

The Very Bright Display

The CS-2302 in a dark room

I think the CS-2302 wins the award for having the brightest display when it comes to calculators. 

The Red Negative Indicator

Even more amazing is the multi-color display.  Yes, in 2017 we live in a world where multi-color displays on calculators are close to common place:  HP Prime, TI-84 Plus CE, TI-nSpire CX, Casio Prizm, and Casio Classpad fx-CP400.  However, the CS-2302 is from the 1907s: a red negative sign indicator


The usual adding machine modes are present:  Constant Mode toggle (K), fix decimal selector complete with Add Mode, and automatic summation (Σ) toggle.

If you are not familiar with Add Mode, it is a mode where the all sums are rounded to 2 decimal places.  You are allowed to add and subtract numbers in dollars and cents without having to press the decimal point key [ . ].  Add Mode is a favorite of many office workers.

Item Counts, AVG, MU

The Item Count adds the number of addition and subtraction operations.  Pressing [IC] gives the item count and twice to clear it.

You can also use the item count to get the average of numbers added by one step with the average key ([AVG]).  Calculating the average clears the item count automatically.

Sharp called the [MU] the multiple use key in the 1970s.  Now the key is called the mark-up key.  It is true that [MU] serves multiple purposes.  Looking at the manual from similar desktop calculators from Sharp, the [MU] allows for cost, sell, markup, margin, and percent change calculations. For example:

Percent Change:  new [ + ] old [ - ] [ MU ]

Selling Price:  cost [ ÷ ] margin [ MU ]

Markup:  sell [ + ] cost [ - ] [ MU ]

Final Verdict

I love the display of the CS-2302 and the big size and steady keyboard.  I wish the CS-2302 had a totals key [ * T ] to complete calculations.  This desktop calculator, and others like it, would be a good ecological alternative for those who don’t want paper tape. 


This blog is property of Edward Shore, 2017

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