EC806S

EC806S has no equivalent designation confirmed by the archive.

The EC806S is a UHF-triode on a Pico 9 (Noval) base with gilded base pins, intended for operation as an RF amplifier and as a self-excited mixer.

Construction

Maximum dimensions conform to DIN 41 539, nominal size 40, form A, and the maximum weight is 14 g. The maximum bulb temperature is 165 °C. The special cathode prevents the formation of a disturbing interface layer even when operated with the heater on and no plate current for lengthy periods. Tolerances of electrical ratings are reduced in comparison with receiving tubes.

Ratings

The heater requires 6.3 V at 165 ± 10 mA. Maximum ratings include an anode voltage of 440 V, anode dissipation of 2.4 W, cathode current of 20 mA, grid voltage of −50 V, grid dissipation of 20 mW, and grid resistor (for automatic grid bias) of 1.2 MΩ. The maximum voltage between filament and cathode is 100 V, with a maximum resistance between filament and cathode of 20 kΩ. The maximum frequency for operation as an RF amplifier is 800 MHz.

Capacitances

Capacitances include a grid-to-cathode capacitance of 3.6 ± 0.6 pF, an anode-to-cathode capacitance of 0.2 ± 0.04 pF, a grid-to-anode capacitance of 2.0 ± 0.3 pF, and a grid-to-filament capacitance of less than 0.3 pF. Additional values are a filament-plus-grid-to-cathode capacitance of 6.6 ± 1.1 pF, a grid-to-cathode-plus-filament capacitance of 3.9 ± 0.6 pF, an anode-to-cathode-plus-filament capacitance of 0.3 ± 0.05 pF, and an anode-to-grid-plus-filament capacitance of 2.1 ± 0.35 pF. With external screening (shield 22.5 mm internal diameter, length 49 mm), the anode-to-grid-plus-shield capacitance is 3.1 ± 0.3 pF, the cathode-plus-filament-to-grid-plus-shield capacitance is 4.2 ± 0.6 pF, and the anode-to-cathode-plus-filament capacitance is 0.25 ± 0.05 pF.

Characteristics

At an anode voltage of 175 V and a cathode resistor of 125 Ω, the tube has an amplification factor of 14 mA/V, a transconductance of 14 mA/V, and an anode current of 12 mA. Negative grid current is less than or equal to 0.5 μA, and grid voltage (at Ia = 0.1 mA) is less than or equal to −5 V. The anode-to-rest insulation resistance is at least 100 MΩ at an isolation voltage of 300 V, the grid-to-rest insulation resistance is at least 100 MΩ at an isolation voltage of 100 V, and the filament-to-cathode insulation resistance is at least 10 MΩ at an isolation voltage of 100 V.

Life and Mechanical Limits

The guaranteed life is 10,000 hours, averaged over 100 tubes, provided the filament voltage is kept within ±5% (absolute limits); the failure rate is approximately 1.5% per 1,000 hours. At end of life, anode current reduces from its initial value to 10.5 mA, mutual conductance reduces to 9.5 mA/V, and negative grid current increases to greater than 1 μA. The tube can withstand accelerations of 2.5 g at 50 Hz for lengthy periods and momentary shocks of 500 g for short periods. Operation with a high cathode resistance and positive grid bias is recommended to keep electrical values constant during life.

Original manufacturer datasheets for EC806S, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

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