On the Space Saving Model M, you can get a number keypad on some letter keys by using shift - numlk. For that mode, I see all the numbers and plus, minus, times and divide but I don't see an equals sign. Where is that?
There is no equals sign as part of the numeric keypad on the IBM PC keyboard. There are the ten digits, the decimal point, Enter, +, -, *, and /, and Num Lock.
So, to type an equals sign, one would have to use the +/= key on the regular keyboard. Some calculator applications might use the Enter key either for an equals sign, as noted, or even as the RPN Enter key.
A different rationale was used for the numeric keypad on the 122-key keyboard, or on IBM terminal keyboards. There, there is a - key, but no other arithmetic operator keys, so it is intended to change the sign of a number to negative rather than as the subtraction operator. There's also a tab key, a space key, and a comma; keys relevant to entering numbers, not calculating with them. There is still an Enter key, and two unused keys, in the positions occupied by Num Lock and / on the numeric keypad on the PC. (* becomes , and - becomes space; the + key is split into two keys, the top one being the Tab key, and the bottom one being -.)
