6S2S

Electron tube 6S2S (6С2С rus.) is an octal-base single triode produced in the USSR for low-frequency voltage amplification and HF front-end use. It is commonly listed as equivalent to the 6J5 / VT-94 and was made in both glass and metal-base variants.

Socket / base: Octal (8-pin)

6S2S is a direct equivalent of the 6J5 / VT-94 (American) tubes.

When substituting, confirm pinout and heater spec (6.3V) — the 6S2S shares many application circuits with half of a 6N8S (per some references) but is a single-triode device.

Technical specifications (at In 6.3 V, Ua 250 V, Uc=-8 V):

• Filament current: 300 ± 25mA
• Anode current: 9 ± 3.5mA
• The same at the beginning of the characteristic (at U=-24V): 20μA
• Cathode emission current: > 40mA
• Reverse grid current: <1.5μA
• Leakage current between the cathode and the heater: <20μA
• Slope characteristics:
• at U=6.3V : 2.6 ± 0.6mA/V
• at U=5.7V : >1.65mA/V
• at U=90V , Us=0 : 3 ± 0.6mA/V
• Gain: 20.5 ± 2.5
• Vibration noise voltage (at Ra-2 kOhm): <150mV
• Slope of characteristic: >1.55mA/V

Maximum performance data:

• Filament voltage: 5,7 – 6,9V
• Anode voltage: 330V
• Grid voltage: 0V
• Voltage between cathode and heater: 100V
• Cathode current: 20mA
• Power dissipated by the anode: 2.75W
• Operating ambient temperature range: from -60°С up to +70°С
• Weight 40 g.

The minimum operating time is not less than 2000 hours.