1941 — Current Regulator Tube

Overview

The 1941 is a current regulator (also designated as r gulateur de courant or Stromregler) designed to maintain a stable current flow across a wide range of applied voltages. Operating with a nominal regulated current of 0.3 A (300 mA), the device is engineered to absorb voltage fluctuations in electrical circuits, providing a constant current output. The 1941 is constructed in a glass bulb envelope and is available in multiple base configurations, including a specialized four-pin base and a standard Edison screw base, to suit different mounting and equipment requirements.

Mechanical Construction and Base Options

The 1941 features a glass bulb envelope with a maximum diameter of 53 mm. Depending on the installation requirements, the device is supplied with one of two distinct base configurations:

• Base A (Type 40465): This is a four-pin base configuration. When equipped with this base, the device has a maximum overall length of 162 mm. This total length corresponds to a maximum height of 144 mm (excluding the pins) combined with a maximum pin length of 18 mm. The active regulating filament is connected between the top and bottom pins (marked as f). The base also includes two auxiliary side pins, identified as pin 1 (left, also labeled 10) and pin 4 (right, also labeled 04).
• Edison Base: This is a standard screw base configuration. When fitted with the Edison base, the device has a maximum overall length of 154 mm.

Electrical Characteristics and Regulation Performance

The primary function of the 1941 is to regulate current to a nominal value of 0.3 A over a specified regulating voltage range of 80 V to 200 V.

To ensure quality and consistency, the device is tested at a reference voltage of 140 V. At this test point, the current is held within tight tolerances:

• Minimum Current ($I_{min}$): 289 mA (0.289 A)
• Maximum Current ($I_{max}$): 311 mA (0.311 A)

Curve and Regulation Behavior

The current-versus-voltage characteristic (associated with curve reference 7R01410) demonstrates the highly stable and flat regulation performance of the 1941.

• Within the Regulating Range (80 V to 200 V): The current remains exceptionally flat and constant at exactly 0.3 A.
• Extended Range and Roll-off: The stable regulation characteristic is maintained at approximately 0.29 A to 0.30 A even down to an applied voltage of 50 V. Below the official 80 V threshold, the current begins to roll off, dropping slightly to approximately 0.29 A at 70 V.

Technical Summary

The 1941 is a glass-envelope current regulator designed to stabilize current at a nominal 0.3 A over an operating voltage range of 80 V to 200 V. Featuring a maximum diameter of 53 mm, it is available in a 154 mm Edison screw base configuration or a 162 mm four-pin Base A (Type 40465) configuration. With a strict current tolerance of 289 mA to 311 mA at a 140 V test point, the 1941 provides reliable, flat current regulation, maintaining a stable current of 0.29 A to 0.30 A across its active operating region.