Speedy HP 67?

[Trent Moseley]

I loaded the exact same program which has a few trig functions into my 67 and 15C. Then I ran the programs simultaneously. I was shocked when the 67 finished considerably ahead of the 15. What goes?

tm

[james summers]

I don't know whether this is the reason but I recall reading somewhere that HP deliberately reduced the speed of the Voyagers in order to give a long battery life. They maybe were not too concerned with the battery life of the '67 as given the drain of the led's it was expected that they would be running (or being charged up) on the mains adapter pretty frequently anyway.

Having just got my hands on a '67 (my job for the weekend is to try and revive the card reader) I will need to give it a run against the 15C.

James

[Valentin Albillo]

Hi, Trent:

However, an HP-15C can invert a 5x5 matrix in 28 seconds and solve a 7x7 system of equations in 21 seconds, while an HP-67 takes "a little longer" indeed ! (though it certainly can carry out these computations) :-)

Also, as you know, the HP-15C can last many, many years on a single set of batteries, versus a couple of hours in the case of the HP-67.

I had one (an HP-67) long, long, long time ago and I loved it very much, but except for the card reader and the ability to read the display (and use the calculator) in total darkness, the HP-15C is by far the better machine.
Anyway, the card reader is such a tremendous advantage that if forced to chose between the one and the other to carry with me to the proverbial (AC-capable) island, it would be a hard choice indeed.

Best regards from V.

[Rodolfo Canet Castelló]

A few weeks ago I was also surprised watching how fast an HP-80 was compared to an HP-12C!

[Trent Moseley]

There is still the unanswered question --- why can the 67 compute faster, at least in most computations, than the 15C?

tm