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Neighbor's house alarm triggers when I put my car in reverse

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Re: Neighbor's house alarm triggers when I put my car in reverse

#241

Post by infogulch »

mabbo wrote: post #229
DonHopkins wrote: post #209

I posted this before in the "My wife has complained that OpenOffice will never print on Tuesdays" discussion [1], but it's worth repeating: I heard a story about a terminal in a public terminal room that a user was able to consistently log in to if they were sitting down in a chair in front if the terminal, but never if they were standing up. They thought it might be static electricity, or some mechanical problem, or…

Had something like that over a decade ago doing tech support for a government reporting agency. Report: "If my secretary logs with our account, it works. If I do, the website logs in but then later shows me errors message when I try to submit a report".[0] Entirely repeatable. Screenshots sent showing it exactly. All of us scratching our heads. How could our web server know who was sitting in front of the keyboard? R…

I would take a different lesson: use internally generated ids, not user generated usernames when communicating between services in your backend.

Re: Neighbor's house alarm triggers when I put my car in reverse

#242

Post by wbl »

IndrekR wrote: post #154
mdip wrote: post #102

Earlier quoted context omitted.

Off topic to the discussion, but you hit on something that struck a nerve with me so I'm going to go with it . . . Oh good God, this happens to me every time one of my smoke alarm batteries starts to go. I have 6 smoke detectors and an older home where they're not all wired/battery back-up but rather all battery powered. The "chirp at 90 second interval" thing is the worst design in the universe and it bites me every…

(Un)fortunately there are things that are written down in standards, like the LED blinking behavior, that the manufacturers can not change if they want to legally sell the devices. You can get a smoke alarm with 10 year battery life to reduce the likelihood of this happening. When all are purchased in one batch, you can then pretty much replace them all at once -- if first battery goes, next ones are soon to follow.…

Can you seriously not add a "Change Battery" LED next to it?

Re: Neighbor's house alarm triggers when I put my car in reverse

#243

Post by logfromblammo »

azernik wrote: post #127
mdip wrote: post #102

Earlier quoted context omitted.

Off topic to the discussion, but you hit on something that struck a nerve with me so I'm going to go with it . . . Oh good God, this happens to me every time one of my smoke alarm batteries starts to go. I have 6 smoke detectors and an older home where they're not all wired/battery back-up but rather all battery powered. The "chirp at 90 second interval" thing is the worst design in the universe and it bites me every…

Vaguely related - I once met a parrot that had learned to imitate that exact chirp . Maddening.

I know a caique that learned how to imitate a ringing telephone. They had to replace all the phones in the house with a different model, because they were constantly looking at dark caller ID panels that didn't ever say "your parrot".

Re: Neighbor's house alarm triggers when I put my car in reverse

#244

Post by mabbo »

infogulch wrote: post #241
mabbo wrote: post #229

Earlier quoted context omitted.

Had something like that over a decade ago doing tech support for a government reporting agency. Report: "If my secretary logs with our account, it works. If I do, the website logs in but then later shows me errors message when I try to submit a report".[0] Entirely repeatable. Screenshots sent showing it exactly. All of us scratching our heads. How could our web server know who was sitting in front of the keyboard? R…

I would take a different lesson: use internally generated ids, not user generated usernames when communicating between services in your backend.

Well technically, the username the user had was generated by us when we signed them up. I honestly think this issue probably would have presented for 1/10 users whose IDs happened to have a leading 0-digit. Our software couldn't handle a situation we had setup for it.

But yes, I do agree with the general sentiment of "communicate via something internal, not something user-supplied".

Re: Neighbor's house alarm triggers when I put my car in reverse

#245

Post by IndrekR »

wbl wrote: post #242
IndrekR wrote: post #154

Earlier quoted context omitted.

(Un)fortunately there are things that are written down in standards, like the LED blinking behavior, that the manufacturers can not change if they want to legally sell the devices. You can get a smoke alarm with 10 year battery life to reduce the likelihood of this happening. When all are purchased in one batch, you can then pretty much replace them all at once -- if first battery goes, next ones are soon to follow.…

Can you seriously not add a "Change Battery" LED next to it?

In theory, you can. However, the standards also mandate that the "annoying" function has to work at least few months after the battery is low. Adding an extra LED there will consume too much power.

Re: Neighbor's house alarm triggers when I put my car in reverse

#246

Post by IndrekR »

kalleboo wrote: post #198
IndrekR wrote: post #154

Earlier quoted context omitted.

(Un)fortunately there are things that are written down in standards, like the LED blinking behavior, that the manufacturers can not change if they want to legally sell the devices. You can get a smoke alarm with 10 year battery life to reduce the likelihood of this happening. When all are purchased in one batch, you can then pretty much replace them all at once -- if first battery goes, next ones are soon to follow.…

You could also just buy the Lithium 9V batteries instead of Alkaline and put in your regular smoke detector - same result https://www.amazon.com/dp/B01684J7P0

If it runs on a standard 9V battery, then a very good option! Newer and smarter smoke detector chips are designed for 3V lithium-manganese dioxide batteries.

Re: Neighbor's house alarm triggers when I put my car in reverse

#247

Post by remyp »

joekrill wrote: post #224
remyp wrote: post #82

This reminds me of a “bug” I found when working for a company that sells package lockers to apartment buildings. We used iPads for the user interface and had monitoring in place to alert us if an iPad went offline. At only one location with two iPads one would go offline almost every day (but not every day) between 12pm and 1pm, for 10-20 minutes. Never the same time of day, and never the same length of time. It was…

Just curious, but what was the ultimate "fix" you landed on? Did you simply move the machine out of the path of the sun? Add a visor or something to the screen or window? Add something to cool the device down when it overheats? Switch to a different device entirely?

We added a $25 sun shade/hood type thing around it and the problem went away. Made the screen easier to see as well!

Re: Neighbor's house alarm triggers when I put my car in reverse

#249

Post by 13of40 »

remyp wrote: post #82

This reminds me of a “bug” I found when working for a company that sells package lockers to apartment buildings. We used iPads for the user interface and had monitoring in place to alert us if an iPad went offline. At only one location with two iPads one would go offline almost every day (but not every day) between 12pm and 1pm, for 10-20 minutes. Never the same time of day, and never the same length of time. It was…

In the 90s I was working a summer job as a forest fire fighter, and one morning the radio kept constantly beeping on one channel. Nobody could figure it out until a couple of hours later we got a call about a fire on a hillside on the other side of town. It turned out there was a radio repeater on the hill and the fire had burned through its power line, so it was beeping to tell us it was running on batteries.

Re: Neighbor's house alarm triggers when I put my car in reverse

#250

Post by BoorishBears »

to3m wrote: post #58
derekp7 wrote: post #3

Earlier quoted context omitted.

I don't know, I would tend to side with the theory that the car engine sound at the specific RPM and power output matches the resonance frequency of one of the house windows. Resonance can creep up in many phenomena.

But the engine speed doesn't change until you lift the clutch. So if this were due to the RPM, putting it in reverse while stationary surely wouldn't do anything in particular.

Fuel mixture changes as the engine heats up, changing the sound
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