Hi Jules,
Still interested to find out about powering the Melcor SC-635?
I got one and succeeded to power it from 2.2 to 3.0V
There is a switching regulator on the PCB (AS1930 from Astec International)
that generates negative voltages (as referred to the negative side of the
battery: -12.4V ,
On 07/22/2018 02:35 PM, Paul Berger via cctalk wrote:
These calculators all have 3 NiCd
cells in them if the batteries where already removed, you may get a clue
from the shell how many cells it was designed for.
Oh, fun... so, I'd found this snippet of info online the other day:
<<<
I have
On 2018-07-22 4:17 PM, Jules Richardson via cctalk wrote:
On 07/20/2018 10:57 PM, Tony Duell wrote:
It is not uncommon for the NiCd cells to act as a shunt regulator in
such
calculators. The charger is of relatively high voltage (say around
9V), it is
applied to the cells through a current
On 07/20/2018 10:57 PM, Tony Duell wrote:
It is not uncommon for the NiCd cells to act as a shunt regulator in such
calculators. The charger is of relatively high voltage (say around 9V), it is
applied to the cells through a current limiter (often just a simple resistor as
you say), and the fact
Here's a link to the instruction manual.
http://www.wass.net/manuals/Melcor%20SC-635.pdf
Note that it says to have the battery in place if you want to run it off the
external ac adaptor.
Sent from my iPhone
On Jul 20, 2018, at 14:06, Brent Hilpert via cctalk
mailto:cctalk@classiccmp.org>>
On Fri, Jul 20, 2018 at 7:40 PM, Brent Hilpert via cctalk
wrote:
> If you want to power it through the charger jack, then you need to assess
> whether there is any internal charging circuitry (rectification,
> aforementioned
> current-limiting R, etc.) sitting between the jack and the cells.
On 2018-Jul-20, at 10:18 AM, Jules Richardson via cctalk wrote:
> Anyone got pinout/spec information for a MOS MCS2529? In particular, I'm
> curious about operating voltage. I acquired a Melcor SC-635 calculator
> yesterday and there seems to be some uncertainty about the output voltage of
>
Anyone got pinout/spec information for a MOS MCS2529? In particular, I'm
curious about operating voltage. I acquired a Melcor SC-635 calculator
yesterday and there seems to be some uncertainty about the output voltage
of its (rechargeable) battery pack; some places say 2.4V, i.e. the pack is
