6DQ5 — Beam Tetrode, Octal | Tubeofile | Tubeofile

6DQ5

Beam Tetrode — Octal

Data: HighHigh quality — base, heater, all universal parameters present, and ≥50% of desirable parameters filled in. Safe to use for design decisions.

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Known Equivalents & Substitutes

6CD66EX66HD5

Similar Tubes (Not Drop-In Compatible)

21EX6

Same tube family but 21V/0.6A series heater — not compatible with 6.3V parallel heater circuits

21HD5

Same tube family but 21V/0.6A series heater — not compatible with 6.3V parallel heater circuits

26DQ5

Same tube but 26.5V/0.45A series heater — not compatible with 6.3V parallel heater circuits

Electrical Specifications

Section 1 — Beam Tetrode

Absolute Maximum

Anode Voltage (max)DC Plate-Supply Voltage (max)990V

Screen Voltage (max)DC Screen Grid Voltage (max)190V

Anode Dissipation (max)Plate Dissipation (max)24W

Screen Dissipation (max)Screen Dissipation (max)3.2W

Notes

The plate (anode) connection is via a top cap (small cap, JEDEC No. C1-1), not a base pin.
Pins 1 and 5 are both Grid No.1; pins 3 and 6 are both Cathode/Suppressor Grid (G3); pins 4 and 8 are both Screen Grid (G2). These dual connections are for low-inductance paths in horizontal-deflection service.
Maximum ratings are specified for horizontal-deflection amplifier service in a 525-line, 30-frame TV system. Peak positive-pulse plate voltage of 6500 V is applicable only when the pulse duration does not exceed 15% of one horizontal scanning cycle (10 µs).
Plate dissipation must be limited in the event of loss of grid signal; a cathode resistor of suitable value should be employed as protective means.
The 26DQ5 is a heater-voltage variant (26.5 V) with identical characteristics otherwise; it is not pin-compatible without a heater supply change.
The DC component of heater-cathode voltage must not exceed 100 V.
Triode-connection data (g2 strapped to anode) is from the RCA manufacturer datasheet. Only µ is stated; gm and ra are not specified for triode mode.

Pin Layout — Octal

1Control Grid (G1)

2Heater

3Cathode

Socket-Compatible Tubes ⚠ Not electrically compatible

21EX6 21HD5 26DQ5

References