6S19P

The 6S19P, written in Cyrillic as 6С19П, is a triode designed as a regulating element in electronic voltage stabilizers. This purpose is stated explicitly in the available bilingual Russian-English sheet. The device has an indirectly heated oxide-coated cathode and a miniature envelope with a nine-contact base. Its heater requires 6.3 V at about 1 A. The number of contacts does not mean it contains several amplifier sections: the 6S19P has a single triode, with the plate connected to several pins as shown in the sheet's base diagram.

The table gives 110 V at the plate, −7 V for the grid supply, a 130 Ω cathode resistor, 95 ± 15 mA plate current, and transconductance of 7.5 ± 1.5 mA/V. Its note relates the −7 V to the grid supply; it should not be read directly as the grid-to-cathode voltage. In the base diagram the plate is on pins 1, 3, 6 and 8, the grid on 2 and 7, the heater on 4 and 5, and the cathode on 9. When selecting or checking a circuit, these connections matter as much as the designation printed on the envelope. The stated limits include 200 V for plate voltage and 140 mA for plate current. The same table allows 500 V on the plate only when switching on with the tube cold; this is not a continuous operating limit.

The document also discusses environmental robustness: operation from −60 to +70 °C, relative humidity of 95–98% at +40 °C, vibration up to 2.5 g and repeated impacts up to 12 g. It gives a guaranteed service life of 2,000 hours, a specification of the sheet rather than a prediction for every specimen or circuit. The second page's curves show how plate current varies with plate and grid voltages and mark the dissipation limit to observe in regulator service. The sheet documents neither a specific audio application nor an introduction year. Documentary source: bilingual 6С19П / Triode sheet, pp. 123–124.