PhilipsData: HighHigh quality — base, heater, all universal parameters present, and ≥50% of desirable parameters filled in. Safe to use for design decisions.
Anode Voltage (typical)Anode Voltage (typical)100V
Grid 1 Bias VoltageGrid Voltage-1
Notes
The triode and heptode sections share a common cathode.
ECH81 and ECH83 are reportedly equal — not even tested differently, only stamped differently. They show different performance values depending on anode voltage application.
Triode section: Va_max 250 V, Pa_max 0.8 W. Used as local oscillator.
Heptode section: Va_max 300 V, Vg2_max 125 V, Pa_max 1.7 W. Used as mixer.