Low battery indicator
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From: D Yuniskis on 22 Jun 2010 16:07 Hi, Last night, kept hearing a short little "tune" (1-2 seconds) throughout the night. Eventually convinced myself it was *not* part of a bizarre dream sequence. Come morning, I actively sought it out. This proved difficult as it would only occur every 4 or 5 minutes and was just a second or two in duration (so hard to localize). Turned out to be a cell phone complaining of low battery (?) [I don't use a cell phone, so would never have considered this possibility]. Phone was "off" so obviously something is waking itself from deep sleep, periodically, to test the battery and then complain that it is low. (presumably, there is some value to this feature?) Of course, we all know smoke/CO detectors like to chirp interminably as their batteries fail. Lacking any real smarts, it is understandable why a smoke detector will chirp *every* "minute" since it basically sits dormant most of the time and just wakes up to "sniff the air" (and the battery!) before going back to sleep. But, what's the rationale in having a *smart* device (e.g., cell phone) take the same sort of uninspired approach? I.e., assuming there is some value in warning the user WHILE THE PHONE IS OFF that the battery needs a charge, why such a naive implementation? Wouldn;t it make more sense to backoff (exponentially?) with the notifications? I assume if the user *used* the phone in this time, he would be more directly notified of the "low battery" status. So, why waste battery playing silly little songs every 5 minutes indefinitely? And, how does this rationale apply to other "persistent" indicators? E.g., the "fasten seat belt", "door open", "headlights are still on", "you forgot your keys, dummy", etc.
From: kelly on 23 Jun 2010 00:27 "D Yuniskis" <not.going.to.be(a)seen.com> wrote in message news:hvr543$k9c$1(a)speranza.aioe.org... > Hi, > > Last night, kept hearing a short little "tune" (1-2 seconds) > throughout the night. Eventually convinced myself it was > *not* part of a bizarre dream sequence. Come morning, I > actively sought it out. > > This proved difficult as it would only occur every 4 or 5 > minutes and was just a second or two in duration (so hard to > localize). > > Turned out to be a cell phone complaining of low battery (?) > [I don't use a cell phone, so would never have considered > this possibility]. > > Phone was "off" so obviously something is waking itself > from deep sleep, periodically, to test the battery and > then complain that it is low. (presumably, there is > some value to this feature?) > > Of course, we all know smoke/CO detectors like to chirp > interminably as their batteries fail. Lacking any real > smarts, it is understandable why a smoke detector will > chirp *every* "minute" since it basically sits dormant > most of the time and just wakes up to "sniff the air" > (and the battery!) before going back to sleep. > > But, what's the rationale in having a *smart* device > (e.g., cell phone) take the same sort of uninspired > approach? I.e., assuming there is some value in > warning the user WHILE THE PHONE IS OFF that the battery > needs a charge, why such a naive implementation? Wouldn;t > it make more sense to backoff (exponentially?) with the > notifications? > > I assume if the user *used* the phone in this time, he > would be more directly notified of the "low battery" > status. So, why waste battery playing silly little songs > every 5 minutes indefinitely? > > And, how does this rationale apply to other "persistent" > indicators? E.g., the "fasten seat belt", "door open", > "headlights are still on", "you forgot your keys, dummy", > etc. I guess the value of the alarm is in letting the user know self discharge has flattened the battery and that it's time to charge it up so it will be usable when you need it. It could be a lot more frustrating to find if the warning inteval was too long (speaking from the experience of having 4 battery powered smoke detectors @ home).
From: d_s_klein on 23 Jun 2010 17:08 On Jun 22, 1:07 pm, D Yuniskis <not.going.to...(a)seen.com> wrote: > Hi, > > Last night, kept hearing a short little "tune" (1-2 seconds) > throughout the night. Eventually convinced myself it was > *not* part of a bizarre dream sequence. Come morning, I > actively sought it out. > > This proved difficult as it would only occur every 4 or 5 > minutes and was just a second or two in duration (so hard to > localize). > > Turned out to be a cell phone complaining of low battery (?) > [I don't use a cell phone, so would never have considered > this possibility]. > > Phone was "off" so obviously something is waking itself > from deep sleep, periodically, to test the battery and > then complain that it is low. (presumably, there is > some value to this feature?) > > Of course, we all know smoke/CO detectors like to chirp > interminably as their batteries fail. Lacking any real > smarts, it is understandable why a smoke detector will > chirp *every* "minute" since it basically sits dormant > most of the time and just wakes up to "sniff the air" > (and the battery!) before going back to sleep. > > But, what's the rationale in having a *smart* device > (e.g., cell phone) take the same sort of uninspired > approach? I.e., assuming there is some value in > warning the user WHILE THE PHONE IS OFF that the battery > needs a charge, why such a naive implementation? Wouldn;t > it make more sense to backoff (exponentially?) with the > notifications? > > I assume if the user *used* the phone in this time, he > would be more directly notified of the "low battery" > status. So, why waste battery playing silly little songs > every 5 minutes indefinitely? > > And, how does this rationale apply to other "persistent" > indicators? E.g., the "fasten seat belt", "door open", > "headlights are still on", "you forgot your keys, dummy", > etc. Stanley tools makes a tool just for silencing cell-phone alarms. Their part number is 57-550 - about $US 60 RK
From: D Yuniskis on 24 Jun 2010 11:40 d_s_klein wrote: > On Jun 22, 1:07 pm, D Yuniskis <not.going.to...(a)seen.com> wrote: >> And, how does this rationale apply to other "persistent" >> indicators? E.g., the "fasten seat belt", "door open", >> "headlights are still on", "you forgot your keys, dummy", >> etc. > > Stanley tools makes a tool just for silencing cell-phone alarms. > > Their part number is 57-550 - about $US 60 No, the fixture used to test these would be more appropriate (hint: the test terminates when the *handle* -- typically hickory -- snaps!) :>
From: D Yuniskis on 24 Jun 2010 11:46
kelly wrote: > "D Yuniskis" <not.going.to.be(a)seen.com> wrote in message > news:hvr543$k9c$1(a)speranza.aioe.org... >> Hi, >> >> Last night, kept hearing a short little "tune" (1-2 seconds) >> throughout the night. Eventually convinced myself it was >> *not* part of a bizarre dream sequence. Come morning, I >> actively sought it out. >> >> This proved difficult as it would only occur every 4 or 5 >> minutes and was just a second or two in duration (so hard to >> localize). >> >> Turned out to be a cell phone complaining of low battery (?) >> [I don't use a cell phone, so would never have considered >> this possibility]. >> >> Phone was "off" so obviously something is waking itself >> from deep sleep, periodically, to test the battery and >> then complain that it is low. (presumably, there is >> some value to this feature?) >> >> Of course, we all know smoke/CO detectors like to chirp >> interminably as their batteries fail. Lacking any real >> smarts, it is understandable why a smoke detector will >> chirp *every* "minute" since it basically sits dormant >> most of the time and just wakes up to "sniff the air" >> (and the battery!) before going back to sleep. >> >> But, what's the rationale in having a *smart* device >> (e.g., cell phone) take the same sort of uninspired >> approach? I.e., assuming there is some value in >> warning the user WHILE THE PHONE IS OFF that the battery >> needs a charge, why such a naive implementation? Wouldn;t >> it make more sense to backoff (exponentially?) with the >> notifications? >> >> I assume if the user *used* the phone in this time, he >> would be more directly notified of the "low battery" >> status. So, why waste battery playing silly little songs >> every 5 minutes indefinitely? >> >> And, how does this rationale apply to other "persistent" >> indicators? E.g., the "fasten seat belt", "door open", >> "headlights are still on", "you forgot your keys, dummy", >> etc. > > I guess the value of the alarm is in letting the user know self discharge > has flattened the battery and that it's time to charge it up so it will be > usable when you need it. But there is no way to *acknowledge* these alarms OTHER THAN to recharge (in the case of the phone) or replace (in the case of the smoke detector) the battery. I.e., it is an incredibly naive "alert" in both the way it announces itself *and* the way it is acknowledged by the user. E.g., the last time my AC/DC smoke detectors (both, simultaneously) started chirping, the only remedy I had was to *unplug* them! Mind you, they are operating on AC *despite* the fact that they have *detected* their backup batteries to be low. So, I have to opt to disable them completely until the stores open in the morning (and, hopefully *remember* to buy replacement batteries now that they have *no* possibility of reminding me!) or listen to them chirp through the night. > It could be a lot more frustrating to find if the warning inteval was too > long (speaking from the experience of having 4 battery powered smoke > detectors @ home). |