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+--- Thread: HP 15C CE key bounce (/thread-21635.html)
HP 15C CE key bounce - Rick314 - 04-22-2024 01:12 AM
(09-03-2023 09:09 AM)ijabbott Wrote: The key bounce on my 15C CE (Lot number 9CJ323) is still really annoying*. I'm planning to return it for replacement under warranty.
* I've tried to clear the problem by pressing each key hundreds of times, which seems to have a temporary effect of reducing key bounce, but the problem recurs after leaving the calculator for a while.
Thank you for your post and I have the same situation. I received a new 15C CE yesterday and encountered key bounce over 10 times in 6 hours of use -- a double-registration of a single key press and release, for several different keys. My unit is the same lot number as yours ("L/NO. 9CJ323"). I have serial number ("Collector's Edition Number") 03528.
After seeing the problem several times without trying, I found I can replicate it by pressing the 9 key 10 times (varying angle, direction, delay, and force), then x<>y to clear the display, then repeat. It happens often enough in normal operation that I too plan to return the calculator for an in-warranty refund and order another from a different supplier.
RE: HP 15C CE key bounce - Uwe-001 - 05-05-2024 12:47 PM
Same problem here, i got a 15C CE via Amazon in February 2024. Keys 8, 9 and 6 bounced nearly at each key press. I have tried pressing the affected buttons many times, perhaps to solve a contact problem. However, this was unsuccessful. As the basic functionality of the calculator is therefore not fulfilled, namely to reliably process key inputs, I have exchanged the device and received my money back.
Some time later I ordered again, this time I received L/NO. 9CJ323, CE No. 06506. This device works well. Maybe I've just been lucky now.
On Amazon, other buyers have also complained about the bouncing buttons. The manufacturer obviously has a quality problem.
RE: HP 15C CE key bounce - Johnh - Yesterday 06:45 AM
I get a double bounce maybe once every 3 or 4 days, and Im using it often each day. It's borderline annoying. It helps to be deliberate and consistent in getting a firm key click. But when it does happen it's never clear why and I can never reproduce it! If I had the means to extend the tolerance between second clicks I'd do it. I'd never need to repeatedly click a key more than say 3 per second and that would be very rare.
RE: HP 15C CE key bounce - Steve Simpkin - Yesterday 11:06 AM
There was some discussion on changing the keyboard debounce time in the firmware of the HP-15C CE to potentially help with this issue. I do not know the results of this change though.
https://www.hpmuseum.org/forum/thread-19886-post-185697.html?highlight=bounce#pid185697
Edit: I would still recommend pursuing a warranty replacement for any unit that exhibits multiple entries with a keypress. The firmware change mentioned above *may* help units that can't be replaced under warranty.
RE: HP 15C CE key bounce - Rick314 - Yesterday 06:07 PM
(04-22-2024 01:12 AM)Rick314 Wrote: My unit is the same lot number as yours ("L/NO. 9CJ323"). I have serial number ("Collector's Edition Number") 03528.
I exchanged that unit for another from the same supplier and received lot number 9CJ323 (same), serial number 03553 (25 later). It had the same problem so this time I requested a refund. The problem was easy to replicate by keying 1 ENTER ENTER ENTER + + + ... and watching the display count by 1. Frequently it counted by 1 on both the key press and release.