JCE Mark II

Even the most casual user of calculators of any era is likely to recognize common brand names such as Texas Instruments, Sharp, or Casio - but would be highly unlikely to recognize the brand of this calculator since the company responsible for it did not survive longer than perhaps a couple of years in the early 1970's.  Today, this is an unusual calculator.

At hand is the JCE Mark II, manufactured probably about 1972 by John Colling Enterprises.  This company, located in Palo Alto, California, seems to fit the pattern of dozens of small startups at that time which entered the calculator competition in that it purchased major components used in its calculators from other makers.  In fact, both the main chip and the keyboard in the Mark II are products of Texas Instruments.

As can be seen, this calculator has (as was common at the time) no dedicated "=" key.  Instead, the "=" sign appears on the "+" and the "-" keys.  Operation with a keyboard such as this is as follows:

Addition:  To add the numbers 15 and 20, the operator first clears the machine with the C key.  The key operations are then 1, 5 and +/=.  The display now shows 15.  Next, the operator presses 2, 0 and +/= with the final key stroke resulting in the machine adding the two stored numbers and displaying the result as 35.

Subtraction:  To subtract the operator must first enter the minuend or the number from which another is to be subtracted and depress +/= to enter that number into the calculator.  The operator then must enter the subtrahend, or the number to be subtracted from the minuend and then the operator will depress the -/= key to perform the actual operation and display the desired result.  For example, to perform 8-6=2 the operator presses 8 then +/=, followed by 6 and -/=.  The screen will then display the result, 2.

In multiplication the operation is more like that of what today's users would think is normal; the two factors (or, if you prefer, the multiplicand and the multiplier) are entered with only the "x" key between them.  However, to perform the multiplication operation the +/= key must be used.  As an example, to multiply 2x4=8, the operator would press 2, then "x", then 4, then +/=.  The display would show 8.

The JCE Mark II also has a K or Constant switch which is used to force the calculator into Constant mode.  After the K switch is moved to K position the next number entered will become the Constant.  Also, the calculator has a three position decimal control switch on the front edge of the case with positions "F 2 3" for floating decimal point, fixed 2-place decimal display and fixed 3-place decimal display.  The calculator displays eight digits; will display an E if any entry exceeds eight digits and a square if any calculational result yields more than eight digits to the left of the decimal point.

What's the D key, you say?  Many early calculators have a key such as this; on these machines the display shuts off automatically after a period of inactivity to save battery life.  Pressing the "D" key restores the display.  However, oddly, the Mark II instructions mention no auto display power off and in fact tell the operator that the operation of either the CE or D key simply clears the last entered number.  If we can get either of these in condition to operate, we'll test that out.

I actually have two JCE Mark II calculators.  On the left is a very early example, with serial number M06074.  JCE calculators of other models with low serials are known to have the code letter preceding the serial.  On the right is serial number 506494M.  It is assumed that the M identifies the Mark II model.

The newer of the two JCE Mark II examples came complete with its presentation case (whose red foam is rapidly crumbling) as well as instructions and warranty card.  

One of the interesting things about the JCE Mark II is that the calculator has what would appear to be a battery door on the back, but which is actually the top of a removable battery cartridge or tray.  This comes completely out of the calculator to accept five AA batteries; the tray has contacts which mate with other contacts inside the calculator when properly installed.  As with most early calculators an adapter was available - but it appears that with the JCE, at least, the adapter was an optional extra and not included with the basic purchase.  Below, the battery tray shown in detail.

The whole JCE calculator enterprise appears to have lasted only 1972-1973 or so, from what little can be discerned from the extant materials and advertisements.  In January 1973 the JCE Mark II was being sold mail-order by JS&A for $75.00 with the AC adapter included; by sometime later in 1973 the price had plummeted to $39.95 from the same retailer, again with adapter.  This reflects the incredible pace downward that calculator prices were making and also, not surprisingly, easily shows why many manufacturers could not survive the drops in prices that the truly huge and integrated makers like Texas Instruments could weather.

"Integrated", you say?  That's right.  JCE didn't make any of the really truly important parts of this calculator - the chip, the keyboard, the display.  Possibly not even the circuit board.  Many companies just like this sprang up - with enough new engineering talent, venture capital, some connections and know-how, some marketing and a supply of expensive-to-develop parts made by much bigger companies, dozens of startups flashed briefly on the scene and failed.  Big corporations like TI could weather the temporary losses on calculators until their manufacturing costs were brought in line by sapping profit from other lines; little companies that just made calculators would die soon in deficit.  Others, not integrated, tried to spend money they didn't really have to do things like start making displays or even integrated circuit chips.  Some made it, some failed.  And a couple got in, made money, and got out safely.  JCE?  Well, this company appears to have died as quickly as it started - and today, collectors should keep an eye out for JCE calculators.

   (Above, front and rear print details from instructions found with JCE Mark II s/n 506494M.)