6S45P

Small Signal Triode — Noval

Known Equivalents & Substitutes

6C45Pi6S45P-E6S45P-EV

Similar Tubes (Not Drop-In Compatible)

Western Electric single noval triode with similar high-gm low-ra design philosophy (mu=43, gm=25 mA/V, ra=1700Ω); different pinout

Philips/Mullard single triode with high gm and low ra (mu=60, Pa_max=4.2W); lower dissipation, different base

WE437A

Western Electric single triode (mu=41, Pa_max=7W); similar dissipation class but different base and pinout

Electrical Specifications

Absolute Maximum

Anode Voltage (max)Anode Voltage (max)150V

Anode Dissipation (max)Anode Dissipation (max)7.8W

Cathode Current (max)Cathode Current (max)52mA

Heater-to-Cathode Voltage (max)Heater-Cathode Voltage (max)100V

Max Grid Resistor

Notes

Cyrillic designation: 6С45П. Western transliteration 6C45Pi (or 6C45P) is used by Sovtek and Electro-Harmonix.
Frame-grid construction provides very high transconductance and low transit-time effects for wideband use.
Four cathode pins (1, 3, 6, 9) and two grid pins (2, 8) — all must be connected to avoid parasitic oscillation.
Grid stopper resistors (100–500Ω) recommended at the socket to suppress UHF oscillation.
Heater potential should be elevated (~75–80 Vdc) to minimise hum and buzz in audio applications.
The -E and -EV suffixes denote enhanced reliability/military quality grades of the same tube.
Sovtek datasheet dated from EHX/New Sensor Corporation production.

Pin Layout — Noval

1Cathode

2Grid

3Cathode

References