Old alarm clocks and many doorbells and telephones emit a signal due to the blows of “hammer” metal hemisphere of the bell.
If you are annoying it’s pretty sharp rattling, stick a bell in place of hitting it square of adhesive tape or medical adhesive tape device will beep “whisper”.
.
Recommend to read
HOUSE FOUR-LEGGED FRIEND
A roof over my head and need a four-legged friend that's guarding your house. It does not require much, but shelter from the weather is necessary and the dog. And to build a kennel is...
AN UNUSUAL BUT SIMPLE
For many years he was a subscriber to "Modeller-designer", learned from your magazine a lot of useful and thanks to him "crush" on the bike (velomobile) theme. But to make own design was...