So now I look at Montagnier's apparatus, which looks even more rinky-tink than my old gadget, and what I see is a sensitive noise detector.

Heat is generated via an air-water-heating pump whereby the blast apparatus, which causes a noise, is placed outside together with the heat exchanger.

The design solves the problem of the overload resistance torque which can lead to the apparatus using inertia and producing noise when training and it can lead to the muscles fatigue too.