Yes you can be saved by the bell.
I was wearing bell bottoms ( we used to call them flares ) in the 70,s.
There are LOTS of terms used in boxing.
A call bell is most often used to get the attention of someone, give an alarm or notice a person about something. They can be used at railroad crossings, fire alarms, school bells and doorbells.
"Saved by the bell" came about as a boxing term. When someone was in danger of loosing the match, but the bell rang before he was counted out, it was said he was saved by the bell.
Saved by the bell is boxing slang from the 19th century, a boxer can be saved from defeat by the 'end of round bell'