How to open a 49G?

[mfleming]

I've thought about upgrading the display on a 48SX I have with a newer black LCD. I've seen the 49G mentioned as a donor, so I recently bought a cheap one on TAS. Trouble is of course I have no idea how to open it and remove the LCD. It doesn't appear to have any visible or hidden screws, and I don't want to just start prying at it to see if it will pop open somehow.

I've looked for but haven't found any teardown description, so I was hoping someone could point to such a post, or tell me how they did it themselves. Any experts out there?

Thanks!
~Mark

[Massimo Gnerucci]

(11-08-2018 01:29 AM)mfleming Wrote:  I've thought about upgrading the display on a 48SX I have with a newer black LCD. I've seen the 49G mentioned as a donor, so I recently bought a cheap one on TAS. Trouble is of course I have no idea how to open it and remove the LCD. It doesn't appear to have any visible or hidden screws, and I don't want to just start prying at it to see if it will pop open somehow.

I've looked for but haven't found any teardown description, so I was hoping someone could point to such a post, or tell me how they did it themselves. Any experts out there?

Thanks!
~Mark

Start from Randy's how-to.

But a 49G is still valuable: why not a 39/40? ;)

[mfleming]

Thanks Massimo! Big mistake on my part. The potential donor is a 39G, not 49G. I do have a 49G that I bought years ago and, despite the rubber keys, I still use all the time in the shop.

~Mark

[Massimo Gnerucci]

(11-08-2018 03:27 PM)mfleming Wrote:  Thanks Massimo! Big mistake on my part. The potential donor is a 39G, not 49G. I do have a 49G that I bought years ago and, despite the rubber keys, I still use all the time in the shop.

~Mark

Well, a 39G is much simpler: just smash it against the wall grabbing it by its screen! ;)

Seriously: I think they are quite similar hardware-wise to a 49G.

[mfleming]

(11-08-2018 03:47 PM)Massimo Gnerucci Wrote:  Seriously: I think they are quite similar hardware-wise to a 49G.

Well Massimo, you were correct. Somewhat like opening a Pioneer. So here's my live 48SX and dead 39G donor. The first time I assembled the 48 I was missing two rows of pixels, so I returned and cleaned the LCD connector strips with DeoxIT Red. Reassembled it and all was well.



I do like those old 48SX calculators!
~Mark

[Massimo Gnerucci]

Yep!
The 48SX with a black display is the sexiest.

[rprosperi]

(11-16-2018 07:42 AM)Massimo Gnerucci Wrote:  Yep!
The 48SX with a black display is the sexiest.

1 +

Best looking HP machine ever! (even for non-RPL fans, hehe...)

[Maximilian Hohmann]

Hello!

(11-16-2018 02:49 PM)rprosperi Wrote:  Best looking HP machine ever! (even for non-RPL fans, hehe...)

I think for that we need a poll... Unfortunateley the poll function of this forum allows only 10 options which is short by a factor of ten.

In my list the HP-48 would not rank within the top 10 for best looks alone. I guess I am biased a little by the industrial design paradigms of the last 10 years, but for me the prettiest HP calculator ever is the 20B. Streamlined, clean, shiny, uncluttered and a beautiful color scheme. Of the classics it would be the HP-21 for the same reasons. A clean black, white and blue keybord below a red-glowing display in a cute little package.

Regards
Max

[Thomas Klemm]

(11-17-2018 09:41 PM)Maximilian Hohmann Wrote:  … for me the prettiest HP calculator ever is the 20B. Streamlined, clean, shiny, uncluttered and a beautiful color scheme. Of the classics it would be the HP-21 for the same reasons. A clean black, white and blue keyboard below a red-glowing display in a cute little package.

If you like the HP-20b:


and the HP-21:


What do you think about the HP-10C:


and the HP-22S:


Even the HP-42S isn't much cluttered:


Kind regards
Thomas

[Jlouis]

The 10c is almost perfect.

Perfection is found in the 15c

[Massimo Gnerucci]

Hardly beatable, if we talk about uncluttered.

[aurelio]

but if we are talking about colors....

[Maximilian Hohmann]

Hello!

(11-17-2018 10:25 PM)Thomas Klemm Wrote:  If you like the HP-20b ... and the HP-21
What do you think about the HP-10C ... and the HP-22S...

They are equally pleasing shape-wise (as is the HP-70 which was one of the first HP calculators that camt to mind when thinking "pretty"). But I am the blue kind of person. When as children we ware asked what their favorite colour is, I would always say "blue". And this has not changed. So eveything else being equal I always prefer the blue model. (Wanna guess what colour my car is ;-) ? )

Regards
Max

[Thomas Okken]

I agree there is a lot to be said for a clean and uncluttered design -- I do like the 42S and 10C a lot -- but despite that, my choice for best-looking HP calculator ever made is the 67, no contest:



I don't consider myself a collector but I do own one each of these three.

[Zaphod]

I don’t think I could dislike any of the HP rpn calcs , they’re all beautiful

Well maybe I’m in the minority if I say I don’t like the 20 keyboard , I want a tilting click, not a push.

[Maximilian Hohmann]

Hello!

(11-18-2018 11:18 AM)Zaphod Wrote:  I don’t think I could dislike any of the HP rpn calcs , they’re all beautiful

Well maybe I’m in the minority if I say I don’t like the 20 keyboard , I want a tilting click, not a push.

This is just about "beautiful" from the looks, not the functions or keyboard feel. If you wanted to include those as well it will be very difficult to decide upon a winner... (e.g. I also very much like the HP-67 as an overall package. All the functions I ever need are there, the keyboard is about the best of any calculator ever made and it has a red glowing display. But it would not be my winner because I don't like the brownish colour scheme much. Why couldn't they stick with the black scheme of the HP-65?).

Regards
Max

[Thomas Okken]

(11-18-2018 12:30 PM)Maximilian Hohmann Wrote:  I also very much like the HP-67 as an overall package. All the functions I ever need are there, the keyboard is about the best of any calculator ever made and it has a red glowing display. But it would not be my winner because I don't like the brownish colour scheme much. Why couldn't they stick with the black scheme of the HP-65?

I'll venture a guess: the shift key scheme used on the 65, with f, f^-1, and g keys, wasn't flexible enough for the 67, so they needed three different shift keys, and therefore three different colors. The yellow and blue legends could be printed on the faceplate, but what color to use for the legends on the keys? You need something that contrasts with both the white number keys and all the other non-white keys. Black was an obvious choice because using any other color would have made the calculator look too gaudy / visually busy, but to use black, you need even the dark keys to be somewhat light, in order to get sufficient contrast.

I don't think this was a design choice they made lightly (OK, I don't think HP ever made calculator design choices lightly!), and they must have been pleased with the result, because three years later, they did the same thing with the 34C: gray keys where all the other Spice models had black ones.