the first model from hps new range of units manufactured by
kinpo in china.
it is apparent that the hp30s is one of hp's attempts to
compete in the scientific calculator budget market. build quality is low
compared to their older pioneer range like the 20s
and 32sii and it does not have that hp feel
about it. its a lot cheaper than the older hp offerings. it
is manufactured in china by kinpo who also make models for texas
instruments. compare it to the ti30xbii.
calculations are formula entry (rpn is long gone). the internal precision is
very good. it appears to perform all calculations to 24 digits of precision, but
only displays a ten digit answer. this appears true of all scientific
functions except for square root. i can only get a 10 digit accurate
square root out of the machine which makes the built in square root key less
accurate than performing the root using logs!
internally it appears to calculate in binary, this can be verified by
multiplying a number repeatedly by 2 and throwing away the integer part.
eventually the number sequence will end. not the case if 10 is used. note
that almost all other machines internally operate in decimal. it gets tan(355/226) radians correct
to 10 digits. see the torture test.
the purple faceplate is removable and you get two other colors in the
package for your amusement. in this series is also the 9s and 9g units which
are more expensive, but not especially more featured.
i've been trying to fool the internal binary, so far i've revealed
this: 2+1e-9-2=0 which it shouldnt be on a 10 digit machine. see also binary