Same Rimlock base, higher current rating (90 mA vs 60 mA, 2x350 Vrms vs 2x250 Vrms) — not a substitute in circuits designed for EZ41's lower ratings
Electrical Specifications
Absolute Maximum
Anode Voltage (max)Max AC Voltage per Plate (Vrms)250V
Heater-to-Cathode Voltage (max)Peak Voltage between Heater and Cathode (max)350V
Rectifier
Peak Inverse VoltagePeak Inverse Voltage (calculated)707V
Voltage Drop (typical)Tube Voltage Drop (estimate)15V
Notes
Designed specifically for vibrator-powered car radio receivers with low current consumption (max 60 mA). The EZ40 is the higher-current sibling (90 mA, 2x350 Vrms max) but is not a direct substitute due to different maximum ratings.
A series resistor must be included in each anode lead to prevent sputtering (momentary flash-over between anode and cathode). Minimum values depend on filter capacitor size: 2x150 ohms with 8 uF, 2x250 ohms with 16 uF, 2x300 ohms with 32 uF.
Since the heater voltage is obtained from the same source as other valves in the set (typically an accumulator), the heater and cathode must be well insulated from each other. Maximum permissible heater-to-cathode voltage is 350 V.
Warm-up time is approximately 22 seconds — shorter than the EZ40 (35 seconds) but still ensures HT is delayed until other valves are ready.
PIV is not explicitly stated in the Philips datasheet; the value of 707 V is calculated from the maximum transformer voltage (2 x 250 Vrms x sqrt(2)).
Voltage drop (Vdrop) is not stated as a single figure in the datasheet — only load characteristic curves are provided (Fig. 3). At 2x250 Vrms with 32 uF / 2x300 ohm, DC output is approximately 260 V at 60 mA.
Vdrop ≈ 15V estimated from the Philips Miniwatt EZ41 Load characteristic (Fig 3, Cfilt=8µF, Rt=150Ω, Vtr=2×250V, Io=60mA → Vo=255V; derivation includes regulation losses so pure tube drop is lower — cross-checked against the 6.3V/60mA car-radio rectifier class (EZ40/EZ80 series: Vdrop=17V). Source: Philips EZ41 datasheet.
Pin Layout — Rimlock
1Heater
2Anode 1
3Internal Connection
4
Socket-Compatible Tubes ⚠ Not electrically compatible