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HP25, dead or alive?
01-16-2017, 06:48 PM
Post: #1
HP25, dead or alive?
Hello everyone, I know that it is a very general post, i'm sorry, but at least I will try to understand more about the HP25 calculator that was given to me by a friend of mine. So: when is ON and RUN, 0. appears on the right side of the display and pressing any button nothing happens. On PRGM it's 0, that's all.
Where should I start? Thank you all for your patience, and any replies.

Emanuele
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01-17-2017, 08:40 AM
Post: #2
RE: HP25, dead or alive?
Nice calculator!!

Maybe better to ask this on:
"HP Forums / HP calculators (and very old HP computers) / General Forum"
Success!

— Dirk Hartland
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01-17-2017, 09:46 AM
Post: #3
RE: HP25, dead or alive?
(01-16-2017 06:48 PM)Flayerty Wrote:  Where should I start? Thank you all for your patience, and any replies.

This indicates most likely a defective ACT (Arithmetic Control Timing) chip. It can be repaired. See: this thread.

Bernhard

That's one small step for a man - one giant leap for mankind.
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01-17-2017, 10:21 AM
Post: #4
RE: HP25, dead or alive?
(01-17-2017 08:40 AM)Dirk.nl Wrote:  Nice calculator!!

Maybe better to ask this on:
"HP Forums / HP calculators (and very old HP computers) / General Forum"
Success!

Thanks!
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01-17-2017, 10:21 AM
Post: #5
RE: HP25, dead or alive?
(01-17-2017 09:46 AM)PANAMATIK Wrote:  
(01-16-2017 06:48 PM)Flayerty Wrote:  Where should I start? Thank you all for your patience, and any replies.

This indicates most likely a defective ACT (Arithmetic Control Timing) chip. It can be repaired. See: this thread.

Bernhard

Thanks Bernard!
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