I had tested the set in my own workshop at home in Holland and everything seemed all right, but I had no time to arrange to actually dive it in water. Two weeks later in France I dressed up in my old Admiralty AVON suit, strapped the regulator on my back, set the pressure to one atmosphere over ambient pressure (we dived in shallow water of 5 to 8 meters, just for the pictures ) and in I went. Cameras were all around me, but something was wrong. As soon as I descended the regulator started to breath with great difficulty and also it made a buzzing sound each time I tried to inhale. I returned to the surface and asked for a little more pressure on the air hose. I descended again, but the problem was not solved. I kept descending, and started acting for the cameras but felt like I was drowning because I had to fight for each sip of air from the regulator. The Italians did not seem to notice and they happily filmed three types of diving apparatus that were there, The first was mine, the 'Aerophora' as they called my regulator, then two standard dress divers and a French Navy combat diver with an oxygen rebreather. They were very pleased with the results.