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
TRAILER CLAMSHELL
I was interested in the design described in the article "Trailer-bedroom" ("M-K" № 9, 1984). The idea is to place in the trailer the whole living room is very tempting. However, the more...
BORING FOR RADIO
When faced with the need to drill numerous fine holes in printed circuit boards for electronic devices, it was found that a power drill in this case is not such a good assistant she is...