Ron Wanttaja wrote:

A 7AC Champ doesn't have any stall warning device.

Its Type Certificate pre-dates the period when stall warning devices were
required.

Incorrect!

The phrase from CAR 3 under which it was certified is almost identical
to today's passage in Part 23:

3.120(f) A clear and distinctive stall warning shall precede the
stalling of the airplane, with the flaps and landing gear in any
position, both in straight and turning flight.

23.207(a) There must be a clear and distinctive stall warning, with the
flaps and landing gear in any normal position, in straight and turning
flight.

The only difference is 23.207 goes on to say that it can either be
accomplished via aerodynamic qualities or a by a device. A visual
indicator by itself, by the way, doesn't qualify.