Re: Replacement for No-Slot Clock

[david@uow.edu.au (David Wilson)]

buggie@callisto.unm.edu (stephen e buggie) writes:
>About six weeks ago, there was a thread on this topic ---- rejuvenating
>the NS Clock.   There _are_ two points on the green daughterboard on the
>"chip" at which an external batter could be attached.  Check with DAVID
>EPSON (New Zealand).  It looks like the external battery is feasible, but
>a trace should be cut somewhere so that the exterenal battery is not
>drained by the dead internal unit.....   [David --- please supply
>details!]     Steve Buggie

I think you may be getting David Empson (of New Zealand) mixed up with me
[David Wilson (of Australia)].

I certainly posted information about the battery in a NSC.

If you remove the ROM chip from the NSC you will be able to see a chip,
PC board and a large letter (A/B/C/D/E/F depending on model of SmartWatch).

Placing the clock chip so that the letter is the right way up (and to the
right hand end of the chip, look for two small terminals to the right of
the letter (above and below). They should be marked - (the top one) and +
(the bottom one). You will see a trace leading from the -ve terminal to
the top righthand corner of the chip inside the SmartWatch. This goes to
both pins at the rh end of the chip then goes past the + terminal to the
external pin on the SmartWatch package (pin 12 or 14 depending on the model).

It looks like the +ve terminal is connected on the other side of the PC board.

If you were to cut the connection between the -ve terminal and the chip,
this would disconnect it. Then you could connect an external battery +ve
wire to the +ve internal battery terminal and the external battery -ve
wire to the chip side of the cut you made in the -ve PC board trace then
the external battery would be used and the internal disconnected.

To see the board layout in more detail, download the file app04.pdf from
the Dallas web site. It is a 4 page document with descriptions of the
Smartwatch options that can be changed by cutting traces and joining jumpers
on the PC board. I think there is an error in this document as it has
the DS1216D diagram twice and no picture of the DS1216E.
--
David Wilson  School of IT & CS, Uni of Wollongong, Australia  david@uow.edu.au