6021

6021 has no equivalent designation confirmed by the archive. Completed sales put the typical price at $14.99 per tube.

Description

The Type 6021 is a premium subminiature medium-mu double triode with separate cathode connections for each section, manufactured and inspected to meet the applicable MIL-E-1 specification. It is intended for operation under severe conditions of vibration, shock, high temperature, and high altitude.

Construction and Ratings

The 6021 uses a subminiature envelope and provides separate cathode connections for each triode section. The heater is rated at 6.3 V, with a maximum heater voltage of 6.6 V. Typical operating conditions include a plate voltage of 100 Vdc and a grid voltage of 0 V. The cathode resistance per cathode is 150 ohms, and the heater-cathode voltage is 0 V. The amplification factor is 35 (within a range of 30 to 40), and the transconductance is 5400 micromhos. The grid voltage for a plate current of 100 microamperes dc maximum is -6.5 Vdc. The heater-cathode construction is designed to withstand intermittent operation, and the tube exhibits freedom from the development of interface resistance under conditions common to on-off control applications.

Applications

The 6021 is a general-purpose tube, particularly useful in oscillator and amplifier applications where power requirements permit the use of two tubes in one envelope. It may also be used as a UHF amplifier. Among its many uses are a number of low-frequency amplifier and oscillator configurations. The tube is subjected to a pulse emission test to ensure optimum performance in pulse applications; this test is performed with a heater voltage of 6.0 V, a pulse voltage of 50 V, a pulse duration of 25 microseconds, and a pulse repetition rate of 200 pulses per second.

Performance Characteristics

Capacitance values with no shield are as follows: grid-to-plate (Cgp) between 1.2 and 1.8 picofarads; input (Cin) between 1.8 and 3.0 picofarads; output (Cout) between 0.20 and 0.36 picofarads for Section 1 and between 0.22 and 0.42 picofarads for Section 2; grid-to-grid (Cgg) 0.013 picofarads; and plate-to-plate (Cpp) 0.52 picofarads. Vibrational noise output is controlled by a "white noise test," which subjects the tubes to a white noise vibration spectrum covering 100 to 5000 cycles per second at a root-mean-square level of 2.3 g's per octave and a peak level of 15 g's. The transconductance change with heater voltage from 5.7 V is limited to 15%. Input resistance is plotted as a function of frequency. Instability may be noted with cascode arrangements at frequencies above approximately 100 megacycles.

Testing and Inspection

The 6021 is manufactured and inspected to meet the applicable MIL-E-1 specification for reliability. In addition to the pulse emission test, a grid emission test is performed with a heater voltage of 7.5 V, a grid voltage of -7.5 Vdc, a plate voltage of 150 Vdc, a cathode resistance of 0 ohms, and a grid resistance of 1.0 megohm. An AF noise test uses a signal voltage of 65 mVac, a grid resistance of 0.1 megohm, a plate resistance of 0.01 megohm, a cathode resistance of 75 ohms, and a cathode capacitance of 1000 microfarads. Envelope temperature is defined as the highest temperature indicated when using a thermocouple of 40 BS or smaller diameter elements welded to a ring of 0.025 inch diameter phosphor bronze placed in contact with the envelope. The datasheet was prepared and released by the Technical Publications Section, Emporium, Pennsylvania, in February 1957.

Per-tube prices from completed sales, 2026-07-11 to 2026-09-11. Matched pairs and quads are divided out. See the price index for how these move over time.

Original manufacturer datasheets for 6021, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• engineering data service

1 further designation appears alongside 6021 in the literature but below the evidence threshold used here, so it is not listed as equivalent.