EL32

Power Pentode — Octal

Mullard

Known Equivalents & Substitutes

CV1052CV9961637VT52OM9

Similar Tubes (Not Drop-In Compatible)

Electrically identical predecessor but uses a different base (side-contact B8B), not pin-compatible

Electrical Specifications

Section 1 — Pentode

Absolute Maximum

Anode Voltage (max)Anode Voltage (max)250V

Screen Voltage (max)Screen Voltage (max)250V

Anode Dissipation (max)Anode Dissipation (max)8W

Screen Dissipation (max)Screen Dissipation (max)1.6W

Cathode Current (max)Cathode Current (max)

Section 2 — Triode Strapped

Typical Operating

Anode Voltage (typical)Anode Voltage250V

Grid 1 Bias VoltageGrid 1 Bias Voltage-20V

Anode CurrentAnode Current30mA

Anode ResistanceAnode Resistance3,100Ω

TransconductanceTransconductance

Heater

Heater VoltageHeater Voltage6.3V

Heater CurrentHeater Current0.2A

Notes

Control grid (g1) is connected via a top cap, not a base pin. Requires a top-cap clip connector.
Suppressor grid (g3) is internally connected to the cathode.
The VT52 designation (RAF) refers to this tube and is NOT the same as the American VT-52 (type 45 power triode). Take care to avoid confusion.
Designed for low-power output stages in AC/DC and car radio receivers. The 200mA heater current allows series-string heater operation.
Maximum grid resistor is only 100 kOhm for self-bias and 600 kOhm for fixed-bias operation — unusually restrictive for a pentode.
Widely used in WWII British military radio equipment including the T1143 transmitter, TR1196 transceiver, and B2 spy set (clandestine radio).

Pin Layout — Octal

1No Connection

2Heater

3Anode

4

References