$1 scientific calculator

[Rick314]

I got my first $1 scientific calculator from a local Dollar Tree Store in 2009. A 2011 closed HP Forum thread discusses it, and it is very impressive for the price. I thought these notes I compiled about it might be useful to others.

Code:

* Look carefully for the dark red key legends, used only in special
  calculator modes: A B C D E F for HEX mode entry.  n <mean> <s> DATA
  for STAT mode entry (DATA) and results.
* Complex example 1+j2 * 4+j8 = -12+j16: CPLX 1 a 2 b X 4 a 8 b = (-12)
  b (16).  Only + - * / are available, not exp, log, trig, sqrt, etc.
* Polar <-> Rectangular example: 3 a 4 b ->r<theta> (5) b (53.1 deg)
  ->xy (3) b (4).
* Statistics example: STAT 3 DATA 2 DATA 1 DATA n (3) <avg> (2) s (1)
  <sum_x> (6) <sum_x^2> (14) <sigma> 0.816.  Clear last entry by CD.
  Clear all by STAT (exit the mode).
* Working Register (x <-> y) example: 3 / 6 <up/down arrow =
  2nd ( keys> = (2, 6/3 instead of 3/6).
* Working Register ("constants") example: 2 * = (4) = (8) = (16) =
  (32) / 2 = (16) = (8) = (4) ...
* HEX mode appears to be 40 bit 2's comp ("0 - 1 =" shows FFFFFFFFFF)
  but it isn't 40 bits.  HEX Mode arithmetic is limited to +/- 1e10-1
  (10 decimal digits) -- Do this: 9999999999 (10 9s) HEX (= 2540bE3FF)
  +/- (= FdAbF41C01), good.  "- 1 =" shows "E" error.  Guess: HEX is
  converted to DEC, 10-digit integer math done, then back to HEX.
  log2(2e10) = 34.2 bits.  So the HEX is limited to 34-bit 2s
  complement operations, ~= +/- 2^33 ~= +/- 8.6e9.
* BIN mode seems to be limited to 10-bit 2s complement (-512 to +511
  decimal). BIN 111111111 (9 1s) can +/- OK, but adding 1 to it results
  in Error (overflow).  Similarly, 1000000000 (-512 decimal) - 1 =
  Error.
* Base Conversion Ranges
   Binary    1000000000 to 0111111111 (10-bit 2s comp, -512 to 511)
   Octal     4000000000 to 3777777777 (10-digit 2s comp octal)
   Decimal  -9999999999 to 9999999999 (+/- 10 digits)
   Hex       FdAbF41C01 to 02540bE3ff (same as the Decimal range)
* Display mode: TAB 0-9 (# of decimal places), TAB . (default general
  display), F<->E (floating point vs exponential toggle, only applies
  to the range 1e-9 to 1e10-1).
* An extra digit is kept in addition to the 10 displayed.  1 + 1e-10 =
  (1) - 1 = (1e-10).  Doing the same with 1e-11 doesn't work.
   * Application: 1 + 1e-10 = x^2 x^2 x^2... (41 times) ~= 3.2e95 and
     is still in range.  This is x^(2^41).  1 + 1e-10 = y^x (2 y^x 41)
     = (the same result).

[Steve Simpkin]

Recently I saw a 2-line scientific calculator similar to the one below selling for $1.99 at the local 99 cent store near me.

https://www.ebay.com/p/Student-Multi-fun...9004734154

[grsbanks]

(03-21-2019 03:05 AM)Rick314 Wrote:  A 2011 closed HP Forum thread discusses it […]

Quoting a post in that thread:

Martin Pinkney Wrote:Reminds me of the '60s when we we actually could purchase Japanese-made electronics. We used to get a kick out of some of the grammar in the instruction books. At the time I remember thinking, they have an American distributor for their products, why can't they cough up a few bucks for a technical writer? But then we would not have had the enjoyment.

Even today I still get a chuckle out of the Casio fx-8000G and fx-8500G when you type an unrecognised command into the text editor. It shows you an "Irregal Command" error...

[toml_12953]

(03-21-2019 03:05 AM)Rick314 Wrote:  I got my first $1 scientific calculator from a local Dollar Tree Store in 2009. A 2011 closed HP Forum thread discusses it, and it is very impressive for the price.

I have one of the same model shown in that thread also and it works fine. All the ones I see in the store now, though, have an inoperative STAT mode. When you press 2nd then STAT, nothing happens. The STAT indicator doesn't come on and the stat functions don't work.

[Eddie W. Shore]

This particular calculator has a decent keyboard.

I bought another 99¢ calculator, not this particular model, and the keys were too soft.

Eddie

[Rick314]

(03-21-2019 07:30 AM)toml_12953 Wrote:  All the ones I see in the store now, though, have an inoperative STAT mode. When you press 2nd then STAT, nothing happens. The STAT indicator doesn't come on and the stat functions don't work.

Today I bought another $1 scientific calculator at a Dollar Tree store here in Spokane, WA. It is in a cellophane wrapper from the "Jot" company. The STAT functions work well, tested by the "Statistics example:" in my original post. This one is actually improved over my prior models -- The hard-to-read dark red labels (A B C D E F n <mean> S DATA) are now white and easy to read. But it no longer includes a separate cover to protect the keys. Everything else looks and feels the same.

[Dave Britten]

(03-21-2019 07:03 AM)grsbanks Wrote:  Even today I still get a chuckle out of the Casio fx-8000G and fx-8500G when you type an unrecognised command into the text editor. It shows you an "Irregal Command" error...

That cracks me up, especially because the manual tries to say it stands for "Irregular Algorithm".