DM42- clock losing time

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rprosperi
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Re: DM42- clock losing time

Post by rprosperi » Mon May 13, 2019 2:38 am

Walter wrote:
Sun May 12, 2019 10:55 pm
rprosperi wrote:
Sun May 12, 2019 10:37 pm
All the original 41 versions (CX or module) included a crystal, were reasonably accurate ...
What does this mean in numbers?
Every machine was different (I guess due to the other components in the 41 as well as mfg. variations) but as I recall, for my 41CX drift was about 1 minute in a month or so, but only as compared to other time sources which were not absolute either. In the military, I occasionally had access to 'official' clocks, but being official did not mean they were necessarily accurate.

Before PCs had access to time servers, NIS-managed cesium clocks, etc. all clocks varied, we just never knew. Or cared.

Leaving obsession and other personality quirks aside, I can't think of a reason the clock in a calculator would ever need to be more accurate than the levels being reported here. 6 minutes in a month does seem like it could be noticeable, but only if you compare it to some other time source you know is better, in which case you have access to a time source you know is better, and can adjust the DM42. So, no problem, right?
--bob p

DM42: β00071 & 00282

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rkf
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Re: DM42- clock losing time

Post by rkf » Mon May 13, 2019 4:13 am

Hans S. wrote:
Sun May 12, 2019 12:01 pm
Jebem wrote:
Sat May 11, 2019 7:03 pm
the worst case scenario for the reported clock issues should be around 6 minutes after 6 months.
Should... I could throw in the ring 38 minutes loss after 14 months.

Hans
8 seconds after 3 days for me, which extrapolates to about 8 minutes after 6 months.
DM42 S/N 00761

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ijabbott
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Re: DM42- clock losing time

Post by ijabbott » Mon May 13, 2019 4:55 pm

I'm pretty sure the last time I set mine was sometime on 31st March (when the clocks went forward in the EU), and it is currently running 86 seconds fast after 43 days, so that's about 2 seconds per day in my case.

DA74254
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Re: DM42- clock losing time

Post by DA74254 » Mon May 13, 2019 7:20 pm

I set my clock on the DM42 when I received it. The first batch in December 2017 (I think).
As H2X, I've never bothered about an accurate time on my calc. I have a smartphone and several PC's for that, in addition to several GPSr's as well.

Anyway, it is now, after abt a year and a half, 3-4 minutes ahead of my internet/satellite adjusted devices.
Esben
DM42 SN: 00245

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rkf
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Re: DM42- clock losing time

Post by rkf » Tue May 14, 2019 8:37 am

rkf wrote:
Mon May 13, 2019 4:13 am
...
8 seconds after 3 days for me, which extrapolates to about 8 minutes after 6 months.
By the way, let's not forget about other (HP) hardware. E.g. the clock of my HP50g was adjusted last time 31st of March (switch to DST), and is now 91 seconds slow. That's (circa 6 minutes after 6 months) only a tiny bit better than my DM42, but has the same order of magnitude. Thus, no need to worry.
DM42 S/N 00761

Logan
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Re: DM42- clock losing time

Post by Logan » Tue May 14, 2019 12:15 pm

Mine is from Dec 2017 as well. I set the clock initially but then realized I really didn't care to see it displayed and haven't looked at it since. Currently about 6 minutes fast.

It doesn't bother me. Not even sure why there needs to be a clock on the calculator. I'll use my calculator for calculations and my atomic radio-watch for keeping time :)
DM42 SN 210

Joe Horn
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Re: DM42- clock losing time

Post by Joe Horn » Tue May 14, 2019 6:34 pm

One more data point: 1 week after setting it exactly, my DM42 (SN: 00609) is 5.25 seconds fast. So that's about 22 seconds fast per month, which is better than some quartz crystal watches I've owned.

keithdalby
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Re: DM42- clock losing time

Post by keithdalby » Tue May 14, 2019 7:09 pm

Ah yes, but what was the average temperature? Humidity? Where in the lunar cycle are we? What was the background radiation during this period? These are all important to know as well.

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TwoWeims
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Re: DM42- clock losing time

Post by TwoWeims » Tue May 14, 2019 9:51 pm

Mine keeps perfect time until I put it in the case. Then the pendulum stops swinging. :oops:
DM42 SN: 3682
HP-15C and HP-16C (Bought originally by me in the 80's)
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RNav
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Re: DM42- clock losing time

Post by RNav » Wed May 15, 2019 1:31 am

keithdalby wrote:
Tue May 14, 2019 7:09 pm
Ah yes, but what was the average temperature? Humidity? Where in the lunar cycle are we? What was the background radiation during this period? These are all important to know as well.
:lol: :lol: :lol:
28c, 28s, 48sx, 17bii, 32s, 33s, 35s, Prime, WP-34s, DM42 (daily user)

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