PalmOS no more? :(

[Tony Duell]

> 
> 
> Tony Duell wrote:
> >
> >I've heard stories of HP Voyager series calculators (10C, 11C, 12C, 15C, 
> >16C) running for 15 years or more on the same set of 3 LR44 button cells. 
> >And being used fairly hard in that time.
> 
> I never get more than 2-3 year out of my 16C...  Maybe I'm using the
> wrong batteries? :-)
> 
> (if the damn thing ever dies I may freak out and need detox.  I just can't
> live without my 11c and 16c.  I use them *every* day.)

I wish I could afford a 16C -- they're truely beautiful machines, and 
probably the best handheld ever for bit-twiddling...

Anyway, I have repaired a couple. AFAIK all 16C used the 2-chip circuit,
the smaller chip being a Nut CPU (similar, but not identical, to the one
called, of course, R2D2. The CPU is the same in all Voyager machines of
that design (the 12C, in particular, was produced for so long that it went
through many different designs), the R2D2 is unique to the 16C. 

Early machines hat the chips and a few passives (clock LC tank circuit, 
memory-maintaing capacitor) on a flexible PCB that was clampled to the 
LCD display. That module comes out of the case, it's connected to the 
convnetional PCB used for the keyboard by a zebrastrip. The second 
version was, AFAIK, electrically the same, but had everything on one 
normal PCB heat-staked to the top caes. Fortunately the chips are on the 
side you can see.

I;ve had a fair amount of trouble with dry joints in Voyagers. I've got a 
couple going again just be resoldering everything. Tedious, but not too 
difficult. Alas the only serious failure I had was a dead R2D2 chip, and 
as I menitoned, that is specific to the particular type of machine.

-tony