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
“COMBINE” SOLDERING IRON
A good soldering iron stand is necessary for the radio Amateurs and all those who deal with soldering. Description of just such a fixture and is offered to attention of readers. The...
BURNER WITHOUT FIRE…
By analogy with existing devices for welding and brazing working "with the light", this device is also called a burner. However, it acts on the mating parts do not flame, and hot air...
