Shown here are the three tubes under test. The upper and lower tubes are filled with a mix of 90/10% Argon/Neon gas. The center tube is filled with 100% Hydrogen gas. The power level to each of the argon tubes is about 18 watts per tube, and the power level to the Hydrogen tube is about 180 watts. Notice the concentrated discharge and greatly increased brightness in the center of the lower Argon tube compared to the upper Argon tube.