DC41W

The Lorenz DC41w is a driver triode, Treiberröhre in the original title, with a directly heated oxide cathode. The provisional sheet is dated 2 March 1942 and refers binding military-development specifications to technical directives for Lorenz D tubes. That establishes development context, not use in a particular set or production scale. Its low, broad pressed-glass foot differs from common cylindrical pin bases.

The filament may connect directly to one dry cell. Nominal voltage 1.2 V, minimum 0.9 V, maximum 1.4 V; specified current range 22–28 mA. Secondary 20 mA is not substituted. Approximate capacitances: grid-cathode 0.6 pF, grid-plate 2 pF, plate-cathode 0.8 pF. Filament consumption retains the stated voltage and range, without inventing battery life.

Both operating points give amplification factor 13, transconductance 0.85 mA/V and internal resistance 15 kΩ. At plate 120 V, grid −5 V: plate current 2 mA; at 90 V, grid −3.5 V: 1.5 mA. Alternative conditions, not mixed values. Maxima: plate 135 V, dissipation 0.4 W, cathode current 3 mA, grid resistance 3 MΩ. Grid-current onset −0.4 V uses 0.3 µA criterion, not cutoff. No audio power, distortion or particular driver transformer is specified.

The pressed-glass foot drawing is viewed from below; socket 024 bD 4021. Labels: A plate, G grid, +H positive filament, two −H contacts; others are unlabelled. No pin numbers or unlabelled-contact functions are invented. Clear maximum dimensions: overall height 36 mm and foot outer diameter 39 mm, the latter not upper-bulb diameter. The specific drawing remains the connection reference even where another type uses the same socket designation. Documentation: Lorenz, DC41w, Triode, Treiberröhre, Vorläufige Angaben vom 2.3.42, one page.