Novus & NSC
National Semiconductor (NSC) sold calculators both under their own name and as the Novus brand. I never had any experience with them until I collected a few. In spite of being good looking calculators with great looking functionality (on the face of things) they underwhelm in actual operation.
Novus International Computer
A pretty good looking calculator with really mushy buttons subject to misses and bounces. Its main purpose is converting between different units. If you ever needed to convert acres to hectares (below the = key), this baby was for you!
The two gold buttons determine whether the subsequent press of a conversion key goes left to right or right to left. You enter or calculate a number, press a gold key and then press the key denoting the conversion. Confusingly, the conversion keys may be labeled either above or below, and in gold (if the key has a non-conversion function) or grey (if it is dedicated to conversions.)
National Semiconductor Mathematician
Some people hate RPN calculators, but I find they work the way I think. (Not a lot of people hate me.)
Again, an awful mushy keyboard. The red C button actually drops the 3-level stack. Accuracy is bad:
2 ^ 3 is 7.999994
and
10 ^ (3 * log (2)) is 7.999995
It has an interesting feature: M+ x^2 (the alternate function on the key above 8) adds the square of the display to the memory. This makes it possible to build a sum of a set of points at the same time as building the sum of their squares. Just repeat the sequence:
<point> F [M=X^2] +
When done, the sum of the squares is in M and the sum is in the display. These are the basic ingredients for calculating the variance and standard deviation of the points.
Of note, I found a reference on page 171 of the Sept 1976 issue of "Popular Mechanics" to this calculator selling for $17.88. (Though you had to buy a minimum of 2 to get that price.)
Compare this to the original selling price of the Novus 650, shown below. 21 months earlier, the same money bought way, way, way less machine. Nothing else in history had ever so rapidly advanced in ability and fallen in price.
Novus 3500 "Sliderule"
Spartan to a fault, I just can't find anything to like about this RPN calculator with another mushy keyboard. No exponential notation, and only 7 digits for negative numbers. Blah.
Novus 650 - aka "Mathbox"
Maybe the worst calculator ever! Full RPN logic, but only 6 digits and only integer calculation. As in "look Ma, there's no decimal key!"
Does that look like a decimal point in the photo? Wrong. It's just a permanently lit dot in the 3rd LED element from the right. The manual calls it a "guide" for addition/subtraction of dollars and cents.
In other words, if you want 1 / 3 don't try:
1 ENT 3 /
This yields 0 because it's doing integer division. Instead try:
1 0 0 ENT 3 /
to see .33 in the display. It's still doing 100/3 = 33 but the extra 2 zeroes entered served to align your work with the calculator's display, such that you can pretend you entered 1.00.
Add in a bad keyboard that skips and bounces, a negative zero bug or two, and you've got a truly bad (but small) device.
I just can't ding this calculator enough! Here's what you see when you turn it on. But it's OK. Just press the C/CE key to get started.
This is in mint condition, with the box and instructions.
Almost all others I've found on the internet seem to be made in Malaysia, but this one is marked "Made in USA" on the rear-mounted label, as well as on the box and both instruction sheets. Inside the battery compartment, the case is marked U517, which may indicate US manufacture in the 17th week of 1975 - which would be about right.
A sticker on the box, above, shows that this calculator sold for $9.97 at discount.
This jibes pretty well with a reference I found in the December 1974 issue of Popular Mechanics, in an article titled "Calculators get smaller, smarter and cheaper", saying that the Novus 650 Mathbox was the "Cheapest calculator - at least as we go to press" at $16.95.
The article illustrates how quickly the pace of technology was growing and how rapidly and surprisingly prices were coming down. It begins:
"Everything else may be going up in price, but calculators aren't - they're coming down, dramatically. Hand-held calculators, news when the first appeared for about $400 each, have now come down to $16.95, with rumors flying of $10 calculators to come.
That's probably rock-bottom, though."
Amusing, no?
The Novus 650 was clearly an attempt to build/sell as cheaply as possible. It didn't have to be good to reach that goal.
Novus 750
Strongly resembling the 650 above, the 750 is a much better calculator. It abandoned RPN and gained a decimal point button along with floating point calculation. It remained a 6-digit machine, but grew a leftmost LED to display the minus sign of 6-digit negative results.
In addition, it has a much better keyboard with keys that register a clear click when pressed.
It's performance is slightly marred by a common bug that allows calculations to produce a result of "-0", e.g. 1-2+1.
In addition, it powers on to an error state.
On 12/14/1975 the Bangor, ME, Daily News ran an ad for the 750 with a price of $9.66.
An ad in the 9/9/1976 issue of the Spartanburg, SC, Herald offered it at discount for $4.99 (regularly priced at $8.95).
Novus 823
A simple calculator from around 1974, strongly similar to the first few Commodores and Bowmars. Very unusually, it ran on 6 type N batteries.
Alas, this one is dead.
NS 600
Just about the same machine as the 650, above, in a different case. The little "Decimal" switch at upper left just turns the fixed decimal point on and off.
NSC 100A
A thin calculator not much larger than a credit card. Note the negative sign on the right!
