Strange noise from alarm clock

We recently replaced an alarm clock because it would throughout the day make this noise (dah duh -- dah duh -- -- dah duh duh duh) all the time.

We replaced it with another radio alarm clock from a different manufacture., but this one does the exact same thing. This one has the time preset you just set the time zone., the lithium battery keeps the clock going.

Anyway, every hour at 45 minutes after the hour, this sound happens. Two alarm clocks from different manufactures both doing the same thing.

Could this be electrical noise? My UPS plugged into the other wall doesn't kick in at these times. And it's every 45 minutes after the hour. It's not real loud, but it is noticable. Doesn't sound anything like the actual alarm, and the radio is NOT on.

Ideas?

Thanks!

Reply to
Edwin Davidson
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Reply to
Art

Cellphone nearby?

kim. xxx

Reply to
kimble

Or an airport.

Ken

Reply to
Ken Taylor

Unlikely to be radar (only once an hour).

How about a water works, water pumping station or storage facility (telemetry).

Reply to
CWatters

I was thinking beacon rather than radar, but you're still right, I was forgetting the time constraint. Nearby telemetry for industrial gear is a good candidate, as is signaling on the mains for control of off-peak water heating, or similar control.

Ken

Reply to
Ken Taylor

AH!!! I think that is it. I will play with this idea more.

The problem did start when we *upgraded* (ha) to GSM.

The radio in my wifes car makes a noise right before her phone rings. Simular, but not identical.

I bet it is communications between the cell phone and the tower. The cell phone is about 4 feet away.

I'll post back what I find out.

Reply to
Edwin Davidson

Turned the volume of the alarm clocks speakers down and then moved the CELL PHONE closer to a TV in the same room and the TV started to make this noise. So the CELL PHONE must once an hour talk to the cell tower. It's a Siemens M56, AT&T, and the tower is less than a mile out my backdoor.

Thanks! The old clock has a new life, and the middle of the night wakeups are gone!

Edwin Davidson.

Reply to
Edwin Davidson

Try putting the phone directly ONTOP of the radio, then ring it, see what a noise it makes then ;-))

Reply to
exxos

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