|How many versions of the HP-35 are there?|
Message #1 Posted by Michael de Estrada on 9 Mar 2011, 12:05 p.m.
According to this museum and many other sources there are 4 production versions of the HP-35, to wit:
1) Version 1, aka Red Dot
2) Version 2, no red dot
3) Version 3, front label with 35
4) Version 4, wider top keys with legends and raised OFF/ON legends
However, there appear to be two variations of the Version 2:
Version 2a - very similar to Version 1 with s/n label outside case, OFF/ON switch nearly flush with case, same bridge contact etc.
Version 2b - very similar to Version 3 with s/n inside battery compartment, tall OFF/ON switch, still has bump on 5 key and buggy ROM, but otherwise same as Version 3.
It's the Version 2a that has been used to create fake Red Dots in the past, although it has been stated that there are significant internal differences in construction between a true Version 1 Red Dot and any subsequent versions.
I offer this for academic discussion and otherwise no particular purpose.