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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

#191

When we were kids (dating myself here), my friend had a TV with a remote control back when almost nobody had a TV with a remote. You would push the channel-change button on it and the channel knob (!!!) on the TV would mechanically turn and the channel would change. Well, apparently, the remote used an almost-audible high frequency to signal a channel change and when his dog ran through the living room, the dog's tag…

When working on plain old telephone system (POTS) multiplexers, I came up with the following story which a service engineer insisted was true:

An elderly lady with several pets called the operator to say that her telephone failed to ring when her friends called; and that when it did ring, her dog usually barked first. The engineer went to investigate.

He climbed a telephone pole next to the house, connected his test set, and rang the line to subscriber's house. The phone didn't ring, but the dog barked loudly. He tried again, now the phone rang.

Climbing down from the pole, the engineer found:

- This was in a country where the ringing was done from one of the wires against ground (not across the pair) (I think it was England).

- A dog was tied to the telephone system's ground post via an iron chain and collar.

- The ground post was in dry, poorly conducting ground.

- The dog was receiving >50 V of ringing voltage when the phone rang.

- With this torturous treatment, the dog would start barking and urinating on the ground.

- The wet ground now completed the circuit and the phone would ring.

OK, this story has a definite "urban legend" ring to it. Mythbusters wouldn't have tested it with a real dog, I guess.

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

#192
post #141

Earlier quoted context omitted.

My smoke detectors made a boast on the packaging they featured a fool-proof low battery indication, without going into any details. I bought half a dozen of them to install in our new house years ago, thinking the nightly find-the-beeping- ^+=¥€ games were finally a thing of the past. When one started beeping, I did the rounds, figuring I'd be back in bed in minutes. Well, I wasn't. Turned out the fool-proof indicati…

Unfortunately as some who isn't colour blind and doesn't have any close friends who are, it's easy to forget about these concerns. I think attention to accessibility issues like this is one of the things that separates great designers from good ones.

Oh, it isn't all bad - now I get to kick my wife out of bed to find the offender, instead.

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

#193

Reminds me of "story of a car that wouldn’t start every time its owner bought vanilla ice cream". http://www.kepner-tregoe.com/blog/help-my-car-is-allergic-to...

That story is so incredibly far-fetched, and further comprised by the not-so-subtle product plugs liberally sprinkled at every turn.

It sounds like it was written or told by an engineering person and then mangled into this BusinessExecutive™-speak by some marketing person.

And the story doesn't have that big a payoff to justify that either.

All the plugging did was make me slightly annoyed and averse towards the brand and that bloody catchphrase.

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

#194
post #83

Earlier quoted context omitted.

Why would someone microwave blueberries?

Making sauce or heating up a muffin, I guess? Or frozen blueberries, but why would anyone buy frozen blueberries.

Maybe they had the kind that grows in the wood and not in the shop? ;) When you pick berries it is normal to store them frozen to have through the winter

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

#195

Earlier quoted context omitted.

The timing sounds like RF interference. I worked in TV a while back, and we were not allowed to have any cell phones (even silenced) on set - they would introduce this crackling sound into lightly-shielded cables near them. The interference would kick in about a second or two before the ringing started, because there's probably some handshake/setup before the receiving phone decides it's actually an incoming call. In…

My layman understanding of the old GSM network is that cells have a control channel that is used to set up calls (and initially also transfer SMS, before it became popular enough to DOS the cells) and then a bunch of channels for handling the actual calls. It may well be that the control channel's initial "wakeup" transmission is done at a very high power to ensure the phone receives it clearly, and then after some b…

Interesting! Would explain why sending a call doesn't push out as much power.

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

#197

Earlier quoted context omitted.

I've heard stories of unplugged loudspeakers turning into AM radios with enough power pumped into the air, so there's that too.

AM radio has all kinds of "fun" properties. https://www.youtube.com/watch?v=GHSuInSkHtA Listening to the tranmission using the arc the tower generates to ground!

Nice! But I like the Russian (or Ukrainian?) approach better:

https://www.youtube.com/watch?v=lMuJKsUjD_o

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

#198
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.…

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

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

#199

When we were kids (dating myself here), my friend had a TV with a remote control back when almost nobody had a TV with a remote. You would push the channel-change button on it and the channel knob (!!!) on the TV would mechanically turn and the channel would change. Well, apparently, the remote used an almost-audible high frequency to signal a channel change and when his dog ran through the living room, the dog's tag…

When working on plain old telephone system (POTS) multiplexers, I came up with the following story which a service engineer insisted was true: An elderly lady with several pets called the operator to say that her telephone failed to ring when her friends called; and that when it did ring, her dog usually barked first. The engineer went to investigate. He climbed a telephone pole next to the house, connected his test…

> OK, this story has a definite "urban legend" ring to it. Mythbusters wouldn't have tested it with a real dog, I guess.

It would be easy enough to test without involving a dog. They've done plenty of electric-shock myths with ballistic gel dummies.

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

#200
post #11

Is it just me who'd love something like this to happen to me? Would be great fun tracking down the source of the problem (if it was my car; probably less so if I was in the house...) There's a lot of options to try to isolate the problem, just thinking out loud here - a) Back into the driveway returning from work. See if alarm goes off. Next morning, see if alarm goes off as you drive out. b) Remove fuse for reverse…

0) Ask neighbor if they have any idea what's going on. Modern alarms usually at least indicate which sensor triggered.

> What does your neighbor think of this lmao

> > I don't have time to stay around because I tend to lag for work and have to leave as soon as I do get to my car.

How ... convenient.

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