How did they know back when the credit card machines were manual that the card was still good?

Question

I know that for really big amounts they called the credit card company. But did they also do it for small amounts of $10-$20? And if so how did it work in a Taxi when there were no mobile phones?

In: 1

Answer 1

>How did it work in a Taxi when there were no mobile phones?

New York City didn’t force cabs to accept credit cards until 2007: https://www.nytimes.com/2009/11/08/nyregion/08taxi.html

>Although New York was late to bring credit cards to cabs, it leapfrogged ahead by pioneering a customer-friendly system that required no signed receipts, no minimum payment, and an interactive device that let passengers swipe the card and add tips themselves.