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Do you still use stand-alone ("pocket") calculators?
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SiliconWizard:

--- Quote from: johnboxall on May 21, 2023, 12:25:24 pm ---Yes. I spend a few hours a day in an environment where we can't have any radio signals, static, etc. So I take in a HP 35s.

--- End quote ---

That would be a good reason. What kind of environment is it, if not too personal?
DrGeoff:

--- Quote from: rsjsouza on January 31, 2020, 05:14:21 pm ---
--- Quote from: george.b on January 21, 2020, 06:53:41 am ---
--- Quote from: Mortymore on January 19, 2020, 12:03:23 am ---Integral of ln(x^2)dx, from -5 to 99 (EDIT: as can be seen in the photo, on Casio FX-991ES display)

Casio FX-991ES -------- 3m15s -------------- 717.9281095
HP 39G II ---------------- 7s ------------------- 717.928109451
HP 49G+ ----------------- 25m 38s ----------- 717.928325369
HP 40GS ----------------- 20m48s ------------ 717.928325369
HP 49G ------------------ 54m54s ------------- 717.928325369
HP 48G -------------- was not able to solve
Microsoft Mathematics on a i5 ---- 0s ------ 717.9281094509898

--- End quote ---

My HP 48G+ finished it, took a long time (sorry, didn't measure it), but it arrived to a result of 717.928325369.

--- End quote ---
My HP35S failed to compute due to the discontinuity, but the 48G emulated on my Galaxy S8 (Droid48) finished in about 45s with the same result of 717.928325369.  :-+

--- End quote ---

Just to add to the numbers. On an old (1980/81) HP15C this took 10m35s and evaluated as 718.0021.
Benta:

--- Quote from: DrGeoff on May 21, 2023, 11:33:25 pm ---Just to add to the numbers. On an old (1980/81) HP15C this took 10m35s and evaluated as 718.0021.

--- End quote ---
And it took you over three years to work that out?
DrGeoff:

--- Quote from: Benta on May 22, 2023, 12:12:40 am ---
--- Quote from: DrGeoff on May 21, 2023, 11:33:25 pm ---Just to add to the numbers. On an old (1980/81) HP15C this took 10m35s and evaluated as 718.0021.

--- End quote ---
And it took you over three years to work that out?

--- End quote ---

And it took you just a little bit longer to see the post...
RoGeorge:

--- Quote from: johnboxall on May 21, 2023, 12:25:24 pm ---Yes. I spend a few hours a day in an environment where we can't have any radio signals, static, etc. So I take in a HP 35s.

--- End quote ---

That's an interesting aspect.  I wonder what would produce most RF leaks, a HP35s, or a smartphone (any model that has a metallic enclosure, on airplane mode, of course).

Asking because I remember a trick from an old magazine, where an AM radio was taped back-to-back with a pocket calculator, so to improvise a detector for pipes/wires position in walls.

The pocket calculator was acting as a source of RF noises, and the audio hissing and squeaking noises produced by the AM radio were changing their amplitude when the two devices taped together were swept across a metal in the walls.

Anybody measured which one would produce more spurious RF, a metal case smartphone in airplane mode, or a HP35s?
Is HP35s in a metal enclosure, or do you just turn it off during measurements?
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