A possible 43S case?

[walter b]

The announced dimensions of the 43S prototypes (66 mm × 155 mm × 14 mm for the mylar folded case) are quite similar to those of the "HP"-300S+ (84 mm × 156 mm × 20 mm). Its display window is wide enough for the announced LCD of the 43S; though will need a sharp knife and/or a file to make it sufficiently high. Please see here. Its precessor, the 300S, even featured slanted keys (the 300S+ doesn't anymore - see here).

Taking into account that good mechanical HW is neither easy nor cheap to manufacture, the 300S+ and/or 300S may be an affordable donor to start with. Just food for thoughts.

d:-)

[jebem]

(01-11-2015 09:56 AM)walter b Wrote:  Taking into account that good mechanical HW is neither easy nor cheap to manufacture, the 300S+ and/or 300S may be an affordable donor to start with.

Halo, Walter,

I have opened my new HP-300S+ NW277AA for inspection some time ago.
I didn't remove the PCB, though, as I didn't want to destroy the (in)famous plastic rivets that HP is so much found of on certain HP models since the 80's.

Maybe one of the other fellows here have totally dismantled his/her 300S+ and could to share it with us?





P.S. - The procedure I use here to link to images stored in external sites was kindlly explained to me by Dave (Thanks again, Dave!).

Code:


code:
[url=http://<url.jpg>][img=300x200]http://<url.jpg>[/img][/url]
Just replace the two strings "http://<url.jpg>" with the http url.

[Thomas Radtke]

Are the keys hinged somehow?

I dislike the arragement of the cursor keys. In case of the 35s those certainly weren't hinged and turned out to be less reliable (on my sample) than the other keys.

[Massimo Gnerucci]

Oooooh!

We finally settled for the arithmetic keys placement.

[jebem]

(01-11-2015 12:58 PM)Thomas Radtke Wrote:  Are the keys hinged somehow?

I dislike the arragement of the cursor keys. In case of the 35s those certainly weren't hinged and turned out to be less reliable (on my sample) than the other keys.

Halo, Thomas,

I like the HP-300S+ case.
It is made of resistant nice plastic in glossy black color except for the gray side frame, very compact and sturdy build, IMHO.

It is quite easy to open the case, and I can confirm that the materials and build is good.
No cracking plastics when separating the upper and lower sides!
There are 4 rubber feet on the back cover, hiding 4 fixing screws that fixes the case parts together.

The enclosure is made of 3 plastic parts:
- Glossy black back cover, where a small battery cover gives access to the LR44
1.5V cell receptacle;
- Glossy black front cover, where the keyboard assembly under the main pcb is fixed using plastic rivets;
- Grey frame to join front and back covers.
Additionally there is a dark grey plastic cover (with 4 rubber feet as well) to slide in and protect the display and keys when not in use.

However I am not happy about the 300S+ keys at all.
The keys are made in hard plastic with printed legends.
There is no mechanical click feedback when pressing them.
We just feel the rubber membrane underneath being pressed, and certainly they are not hinged.
The 300S+ keys works like any low end calculator, like the CASIO FX-991 series for instance.

And while we are at it, the LCD display quality has plenty of space for improvement, IMHO.
The viewing angle is limited and those kind of blue-green digits on a greenish background is something I used to see in low end equipment more than 20 years ago.

In the end, if we put these feature constrains against its cheap price, well, we get what we pay for.

[walter b]

(01-11-2015 12:58 PM)Thomas Radtke Wrote:  Are the keys hinged somehow?

I've got only a 300S. I opened it today, drilled up the heat stakes, and found (unexpectedly) individual keys; these keys aren't hinged in any way but sit on a common rubber mat. The rubber mat looks identical under the cursor block like under the other keys, just the diameters of the key contact circles differ. The (slightly rounded) rectangular key holes in the front plate are 11 mm wide and 7,9 mm long for the big keys and 9,2 mm wide and 6,2 mm long for the small keys.

If anybody has disassembled a 300S+ to that stage: it would be interesting to know if the keys of the 300S and 300S+ are interchangeable. If true, the keys of a 300S in a front plate of a 300S+ may combine the best of these two worlds.

To make my suggestion crystal clear: I don't recommend copying the 300S or 300S+ in any way for the 43S - I just think we may butcher these low cost calcs to get some parts we can re-use or repurpose as long as we can count the really existing 43Ss easily using zero, one, or two hands. Producing our own plastic parts may become economical significantly later.

d:-)

[Massimo Gnerucci]

(01-11-2015 03:10 PM)walter b Wrote:  Here you get the individually interchangeable keys you wanted.

d;-)

Well, I really hope not to have this at the mentioned price... ;)

[Thomas Radtke]

(01-11-2015 03:07 PM)walter b Wrote:  To make my suggestion crystal clear: I don't recommend copying the 300S or 300S+ in any way for the 43S - I just think we may butcher these low cost calcs to get some parts we can re-use or repurpose as long as we can count the really existing 43Ss easily using zero, one, or two hands. Producing our own plastic parts may become economical significantly later.

Instead of dismaying the target audience with a Frankensteins Taschenrechner like prototype, how about a kickstarter campaign?

[Thomas Radtke]

(01-11-2015 03:18 PM)Massimo Gnerucci Wrote:  Well, I really hope not to have this at the mentioned price...

Somehow I feel you'll have to pay twice as much to get even that :-P.

just joking

[Massimo Gnerucci]

(01-11-2015 06:33 PM)Thomas Radtke Wrote:  

(01-11-2015 03:18 PM)Massimo Gnerucci Wrote:  Well, I really hope not to have this at the mentioned price...

Somehow I feel you'll have to pay twice as much to get even that :-P.

just joking

I would be happy knowing there's something to be had...

[anetzer]

(01-11-2015 06:29 PM)Thomas Radtke Wrote:  Frankensteins Taschenrechner

The Team will be able to decide what solution is most usable for prototyping.

But I di sincerely hope and guess that there will be better solutions for the final product than gutting a, well, ugly! calculator with such keys...

[brouhaha]

It's an intriguing idea, but we can't make the electronics, LCD, and batteries fit in that. Neither the button cell nor the solar panel provide anywhere near enough power for a 43s (or even a 34s). It's really quite remarkable how much those are able to do with so little power. I don't know about the 300s or 300s+ specifically, but calculators in that market segment generally use a masked-ROM 8-bit low-voltage microcontroller that runs at a really low clock frequency.