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33C key not working
03-23-2020, 10:24 AM
Post: #1
33C key not working
My recently acquired 33C works great except the SST key does not work at all. The key can be pressed normally and "clicks" as it should but it does nothing. This prevents me from reviewing programs (SST/BST) and changing the decimal display (FIX).

I am very reluctant to open the calculator as the Spice case is very brittle and the screw posts break very easily (ask me how I know).

Except for this the calculator in in great shape but I'd love to have it work as it should.

Any ideas?


11C 12C 15C 17BII 18C 19BII 21 25 27S 28S 32E 32S 32SII 33C 33S 34S 35S 38C 39gs 39GII 40gs 41C 41CV 41CX 42S 45 48G+ 48GII 49G 49G+ 50 67 71B 97
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03-23-2020, 06:25 PM (This post was last modified: 03-23-2020 06:25 PM by aurelio.)
Post: #2
RE: 33C key not working
(03-23-2020 10:24 AM)Moggul Wrote:  My recently acquired 33C works great except the SST key does not work at all. The key can be pressed normally and "clicks" as it should but it does nothing. This prevents me from reviewing programs (SST/BST) and changing the decimal display (FIX).

I am very reluctant to open the calculator as the Spice case is very brittle and the screw posts break very easily (ask me how I know).

Except for this the calculator in in great shape but I'd love to have it work as it should.

Any ideas?

Hi Moggul, may I know please if, performing the selftest, you get an error message ?
If you break the posts (I hope not so), it'easyer, anyway, to fix them and of course you should not worry, at least, to compromise the calculator's functionality like it could happen with other machines (41), don't be scared of that... maybe the contact of that key is just dirty and just needs to be cleaned...
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03-24-2020, 08:48 AM
Post: #3
RE: 33C key not working
(03-23-2020 06:25 PM)aurelio Wrote:  Hi Moggul, may I know please if, performing the selftest, you get an error message ?
If you break the posts (I hope not so), it'easyer, anyway, to fix them and of course you should not worry, at least, to compromise the calculator's functionality like it could happen with other machines (41), don't be scared of that... maybe the contact of that key is just dirty and just needs to be cleaned...

Thank you Aurelio.

The self test comes as full 8's and the calculator operates normally.

I have opened a couple of 32Es and the posts are very brittle so I am quite reluctant to open this fine unit. Also when opened, series 3 machines tend to show display errors as the LCD contacts come a bit loose.


11C 12C 15C 17BII 18C 19BII 21 25 27S 28S 32E 32S 32SII 33C 33S 34S 35S 38C 39gs 39GII 40gs 41C 41CV 41CX 42S 45 48G+ 48GII 49G 49G+ 50 67 71B 97
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03-24-2020, 11:59 AM (This post was last modified: 03-24-2020 12:02 PM by aurelio.)
Post: #4
RE: 33C key not working
(03-24-2020 08:48 AM)Moggul Wrote:  Thank you Aurelio.
The self test comes as full 8's and the calculator operates normally.

I have opened a couple of 32Es and the posts are very brittle so I am quite reluctant to open this fine unit. Also when opened, series 3 machines tend to show display errors as the LCD contacts come a bit loose.
thank you for the feedback, it seems to be a mechanical/contact issue. I've not other advices, you should check inside, I guess, under the keyboard, although I understand your reluctance in opening the calculator: if not absolutely required I never do it.
I opened in past times some of those spices with soldered and un soldered component, to solve problems due to ribbon corroded by batteries' leakage, once only successfully, but you won't believe me.. I've been always very lucky with posts and screws.
If you had a mint calculator, I mean cosmetically very nice, but defective, would you swap it with a worn one, full of scrapes but perfectly working? Smile
This is the question...
Also for this reason sometimes collectors own duplicates
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