Solve the Mystery of the Alarm Signal: Duncan's Story

[duncan108]

TL;DR Summary

A phantom broadcast signal taking over the electrics

Hello,

When I tell this story, I usually get brushed aside for being senile but people who know about physics might be more useful.

About a week ago I was woken up with an alarm from my clock-radio. That was odd as I had never used the alarm function. Unable to find the cause, I assumed the electronics had gone hay-wire.
I swopped the radio for a standard FM/DAB, with no clock or alarm. The radio was off at night but still plugged in. That night the alarm signal came out of the radio; it was a continuous beep beep.
I unplugged and switch off all power in the bedroom. Next night, the alarm went off again. This time, it was coming out of the light hanging from the hall ceiling. Stay with it.

The following night, I filmed the event and recorded the sound.
The signal started at 23.59. The alarm sounded for precisely 60 seconds and when it stopped the time was 00.00, midnight.
This reminded me of the Speaking Clock. “At the third stroke, it will be precisely, etc . . . .”
I know all radio-controlled clocks are not exactly the same and standard clocks can be all over the place.

Is this a synchronising signal broadcast so that people can align their clocks super accurately?
If so, where might it be coming from. I’ve written to the radio-controlled clock people in Cumbria but not had a reply yet.
How can it penetrate my electrical devices, and how can it turn them into a sort of cat’s whiskers radio?

And how can I stop it?

.mov or .aiff files are not supported for attachment so I cannot send the recording.
Duncan

 

[jedishrfu]

So its either a timing signal from the power company or a smoke detector with a low battery.

The BBC has a signal called the Greenwich Time Signal aka pips:

https://en.wikipedia.org/wiki/Greenwich_Time_Signal

 

[sophiecentaur]

Three independent sources of these 'disturbances'? Are you sure that it's not just one source and the illusion is that it's three? Basically I have no idea but I would definitely stick at it until you get a solution.
If you want to offer sounds and videos, I think it may be necessary to use an account on YouTube or some other service. If you already have one then it is easy - go to the "Insert ,,," tab and go to Insert Media. There is a vast list of alternatives and, if you can find one you are familiar with then off you go and use it as your source. That may be an easier one to solve than your original problem,

 

[jedishrfu]

That's why I mentioned the smoke alarm. I had that happen to me once. I'd hear a chirp and thought it was the radio, then another alarm and finally located the smoke alarm doing it.

 

[jedishrfu]

Another possible source is a wristwatch or alarm clock stashed in a drawer somewhere with a default alarm at 11:59.

 

[russ_watters]

That's why I mentioned the smoke alarm. I had that happen to me once. I'd hear a chirp and thought it was the radio, then another alarm and finally located the smoke alarm doing it.

When I have a smoke alarm chirping I have a lot of trouble figuring out which one. Something about the sound makes it hard to locate.

 

[jedishrfu]

I think its due to reverb issues inside a home. The sound is such that you can't echolocate it easily.

 

[duncan108]

The signal can be heard here:-
www.vitalitywinners.com/alarm480.mov

It’s not a smoke alarm, nor a digital watch nearby, nor anything from another radio, nor an alarm coming through the wall from next door, nor a smart meter having a tantrum, nor an echo bouncing around.
I even brought in a witness at midnight to verify it.
If anyone wants to make any comments, they have to start off with the premise that everything I wrote in that first posting is correct and is how it happened.

 

[Vanadium 50]

If anyone wants to make any comments, they have to start off with the premise that everything I wrote in that first posting is correct and is how it happened.

Clearly aliens.

Seriously, you might be a little more gentle on people trying to help, rather than starting off gunning for bear.

 

[russ_watters]

The signal can be heard here:-
www.vitalitywinners.com/alarm480.mov

It’s not a smoke alarm, nor a digital watch nearby, nor anything from another radio, nor an alarm coming through the wall from next door, nor a smart meter having a tantrum, nor an echo bouncing around.
I even brought in a witness at midnight to verify it.

I recognize the sound. It's a digital alarm clock or watch or modern device copying it with a stock sound. I've owned ones that make exactly that sound. What I suspect happened is a power failure reset the alarm to midnight and it's the type with a physical switch. You'll have to look harder to find it.

A light fixture is incapable of producing such a sound. But the worst case scenario here is someone is playing a prank on you and has hidden the alarm in the room.

If anyone wants to make any comments, they have to start off with the premise that everything I wrote in that first posting is correct and is how it happened.

That isn't reasonable. If you had a complete and accurate explanation you wouldn't be here asking for one. Every potential explanation starts with you having missed or been mistaken about something.

 

[berkeman]

I even brought in a witness at midnight to verify it.

Were the two of you able to track it down to a room in the minute you had? If not, could you get them back and maybe one other person, and all be stationed in the house in different places to start localizing it? I'd also open up the attic access and all of the closed/pantry doors for this search.

With enough people, you should be able to track down the source of the sound, at least to within a couple of meters, hopefully.

 

[DaveC426913]

Every potential explanation starts with you having missed or been mistaken about something.

I'm with Russ on this.

Electronic sounds like this - high-pitched and pure - are notoriously difficult to locate. Many times, I have torn a room apart, trying to find a source because every time I think I'm nose-to-nose with the culprit, it's just not there - and is now coming from a completely different part of the room. Sometimes it can take days to track a source down.

While it is not impossible your devices are somehow emitting alarms, I suggest that - if you're hearing hoof beats - you should look for horses before zebras.

 

[jedishrfu]

I agree with Russ, its definitely a digital alarm going off and the notion of a power outage causing it to be reset to midnight is highly likely. It would have to have been an outage of short duration to keep the time at around midnight or you had fixed the time on the device but didn't know it had a built in alarm feature too.

You should check if your TV or other appliances like phones, digital photo displays, microwave or stove or radios of any kind that are electronic and that may have an alarm feature.

Have you had any work done at your home recently? Perhaps a worker left something behind or your kids/grandkids have some sort of toy with an alarm they left behind.

 

[A.T.]

When I have a smoke alarm chirping I have a lot of trouble figuring out which one. Something about the sound makes it hard to locate.

This video explains nicely why sounds with a single high frequency are difficult to locate:

 

[berkeman]

If anyone wants to make any comments, they have to start off with the premise that everything I wrote in that first posting is correct and is how it happened.

When I was in undergrad, I lived in a 2-bedroom townhouse for a year with another EE student, a ChemE student and a Physics major. It got a bit rowdy sometimes, including some times when I wanted to study.

I got home one time after they had just left, and settled down at the living room table to study. They had left the stereo on, blasting through a set of headphones on the other end of the couch away from me, so I reached over to the stereo next to me and shut off the power switch.

But the music kept blaring out of the headphones, which I could clearly see were connected to the stereo with a long cord running across the couch. This was a bit strange, so I pulled the jack for the headphone cord out of the front of the stereo, and still the headphones kept blaring!

I could not take it anymore, so I walked over the the headphones and started tracing their cord. Turns out they were plugged into a clock radio on the other end of the couch on a side table, not into the long extension cord from the stereo.

So I try to keep an open mind on stuff like this, but I never assume that I understand what could be going on until I have the solution actually in hand.

And I second the pranking possibility. Especially if it turns out that you track the sound down through the attic and it's some battery-powered something that got dropped between walls...

Let us know what you find please.

 

[jedishrfu]

That's a nice video on echolocating and for me, it was a duh moment as it took the stuff I knew but never connected together to explain why it's hard to track these high-pitched sounds.

It also brought out the fact that bird calls have evolved in a way to thwart some predators but not necessarily other birds.

 

[anorlunda]

A stethoscope is an inexpensive and simple device useful for locating sounds.

I would try it while the beeping is ongoing. Try all the furniture, 4 walls, ceiling, floor

Then keep the stethoscope. It is also very useful for strange sounds in cars and trucks.

 

[Vanadium 50]

My postdoc experiment had a half-dozen or dozen "sonalerts". These are buzzers - beepers really - that give off a tone when something goes wrong. We ordered them with different sounds, pitch, fast or slow beep, etc. Purchasing, however, saved a dollar - maybe two - by getting them all the same.

When one went off, the shift crew went into a mode I called "laying on of hands" - covering the sonalerts to try and figure out which one was going off.

 

[duncan108]

Thank you everyone for your attention, suggestions and effort.
The thing is I am very low on technical equipment - no television, aerial or satellite dish; no mobile; only one clock radio; no hi-fi; no microwave; no smart meter; cameras always off and never on charge overnight; computer connected with ethernet and shut down at night; no pranksters or workmen near the place. An electrician came and checked everything and found nothing strange. I have had a lot of aggressive troll-type comments from other sources in the past week, such as, “You’ve obviously got another alarm clock in a cupboard, you moron”.

 

[Dullard]

Wristwatch. Casio, I think.

 

[anorlunda]

Take my hint about the stethoscope. Your first priority should be to find where the noise is coming from, not to guess what the source is.

 

[phinds]

Just listened to you sound MOV and I absolutely agree w/ everyone else - - - definitely a digital device of some kind.

 

[Nik_2213]

We tracked something similar to a travel-clock in a 'weekender' bag. Given the skew time, we reckoned it had been reset by a jolt shifting batteries, defaulted to midnight...

Another such was reset thus by one of our 'poltercats' knocking it aside...

Usual perp is a smoke alarm demanding a new battery when lowest ebb of house temperature sapped voltage output. As widget had come in a multi-pack, there were four suspects. And, no, even from inches away, I could not identify the source with confidence. Exasperated, I had to remove batteries from each in turn until I silenced the 'Peep !' With great sigh of relief, I replaced battery by spare held for this specific task, staggered back to bed...

( 'Poltercats' is apt description, given our hyper-mischievous spotty moggins will steal USB drives and adaptor cables, empty 'pending' tray onto floor, un-latch network cables etc etc. Once, I glimpsed BossCat & 'Minion du jour' dragging away USB corded mouse they'd un-plugged, followed them to stash... )

 

[berkeman]

Were the two of you able to track it down to a room in the minute you had? If not, could you get them back and maybe one other person, and all be stationed in the house in different places to start localizing it? I'd also open up the attic access and all of the closed/pantry doors for this search.

With enough people, you should be able to track down the source of the sound, at least to within a couple of meters, hopefully.

Thank you everyone for your attention, suggestions and effort.

Hopefully you can get enough helping hands, er, ears to track down the source. If you would rather not buy an inexpensive stethoscope, another option is to use a simple drinking glass to listen to the walls. Our ears are hard to press flat on walls (don't ask me how I know this), but a drinking glass helps to couple the sound inside the wall or in the next room to your ear. I work part-time in EMS so I have my stethoscope and have used it to track down unusual noises several times.

https://previews.123rf.com/images/s...listening-through-the-wall-with-the-glass.jpg

 

[sophiecentaur]

Our ears are hard to press flat on walls (don't ask me how I know this), but a drinking glass helps to couple the sound inside the wall or in the next room to your ear.

This is highly suspect information as it a well known way of snooping on the activities of the neighbours in your typical seedy No-tell Motel. (So they tell me).

 

[A.T.]

This is highly suspect information as it a well known way of snooping on the activities of the neighbours in your typical seedy No-tell Motel. (So they tell me).

@duncan108 Speaking of neighbours, are there any? Could the alarm come from a different house/flat?

 

[berkeman]

This is highly suspect information as it a well known way of snooping on the activities of the neighbours in your typical seedy No-tell Motel.

Hey! I'm a medical professional.

 

[sophiecentaur]

Hey! I'm a medical professional.

So why were you in that motel room when I saw you last?

 

[sophiecentaur]

but a drinking glass helps to couple the sound inside the wall or in the next room to your ear.

Imagine the labels in hardware stores, describing their drinking tumblers as "acoustic impedance matching units".

 

[duncan108]

That video is useful, explaining how different tones can be deception for position and direction of travel.
I’ll try the stethoscope option and get extra witnesses as listeners. I am rather poorly at the moment so midnight escapades aren’t a good idea, but as soon as poss . . . . . . Thank you

 

[omega_minus]

One thing you could try to see if it’s battery powered or coming from the mains is to kill your main incoming circuit breaker right when it starts or possibly a bit earlier. If it doesn’t go off it could be something plugged in somewhere.

 

[russ_watters]

 

[jedishrfu]

Wow that’s a great video. He should’ve stretched it out a bit and uncovered Al Capones secret vault.

 

[A.T.]

That's great, but uses a lot of equipment.

I wonder if one could use some simple listening cone and point it in different directions, to estimate the source direction based on the volume changes.

 

[jedishrfu]

I think the video would be too long if he used one mic at a time with a cone. :-)

Also, this guy was clearly rather impatient to find the source of the beep.