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Billesley Memories of the 1960's: strange sounds from the light fixtures

Seldon2k

Seldon2k

New Member
I hope that someone elso who lived nearby in the 1960's may also confirm my recollections of hearing
what sound like Morse code coming from the incandescent light bulbs.

The location was about halfway down Trittiford Road, between the Common and the Park.
The time was usually in the evening/night.
It sounded like a series of buzzings of varying duration, these coming from the filaments of the light bulbs.

My best guess is the house wiring picking up a strong morse code transmission from a local Radio Amateur.

Does anyone else recall hearing this or know of any Amateur opperating in the area from 1964 to 1972.
It may have been from 1966 to 1970 but memories fade.
 
When the filament gets really thin, it is also very flexible at that point and this let's the filament oscillate due to magnetic forces caused by the flow of current It tries to oscillate and causing buzzing at 120 Hz (or 100 Hz) because of the mains sinewave input.When it does this, it hits the filament supports and this produces the sound you hear. this oscillation in the filament. can be as much as a millimeter or so.This is more vigorous with more current, which is why lamps tend to destroy themselves at switch-on, when a large current flows for a few cycles.

incandescent bulbs can also buzz for a few different reasons. One common cause is a loose filament inside the bulb, which can vibrate and create a buzzing sound. Another cause could be a loose connection between the bulb and the fixture, or between the fixture and the electrical wiring. In some cases, the buzzing could be due to the bulb being incompatible with the fixture or voltage.



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Hi and welcome to Birmingham History Forum. I recall there were quite a few amateur radio operators, who worked under the radar because of the legality’s with the Post office. So, it’s a possibility there could have been one or in and around Billesley.
 
one member on here lives at that location and he is a ham.
ps i never worked under the Radar as a ham only as a cb operator i waited till i past my city and Guilds and got a licence to TX
:)
 
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