Notes:

This is a scientific calculator with two memories, statistic
functions, angle conversions and parenthesis. Some of the
functions listed below are also found in other Commodore
calculators, such as the Commodore SR1800. A main difference between
the SR1800 and this one is the number of keys. Except for the
reverse trigonometric functions there's only one function per key
(no "INV"key required).
Some nice and some less nice features that are worth mentioning:

The "dr"key not only switches between "degrees" and
"radians" mode, but also converts the number currently in display
from one angle mode to the other. For example, when the
calculator is in "degrees" mode, and the number 180 is displayed,
pressing the "r"key will convert the angle to π
degrees. When the calculator is in "radians" mode, the rightmost
dot on the display is lit.

The "→P" and "→R" keys convert between
vector modes. The parameters need to be present as "x" and "y",
and can be entered using the "x↔y"key. The results
can be read using the same key.

The "EE↑"key and "EE↓"key shift left
and right in scientific notation. However, when the number shifts
out of display, the number is truncated. This can not be used to
round the number, because no rounding off takes place.

The "Σ1"key is what is nowadays usually denoted by
"M+", it adds the number displayed to the first of the two
memories.

This calculator feels quite fast.

This calculator as a builtin rechargeable battery. Most of the
time when I find a calculator with a builtin battery the battery
leaks and is often beyond repair because of that. This one
however is different, the battery is working fine at the time of
writing (September 2006) and still keeps its charge. Even so I
took them out as a precaution anyway.
The internal rechargeable battery exists of three AA
rechargeables made by BEREC.
Many thanks to Arnoud Helmantel for finding this calculator for me.
