Same UX4 base, 5V directly heated full-wave rectifier — similar current rating (225 mA) but directly heated with different voltage drop characteristics
Same UX4 base and pin-compatible but mercury-vapour type — lower voltage drop (15V vs 23V), requires 30-60s warm-up before B+, temperature-sensitive. Not a true drop-in due to different characteristics
Electrical Specifications
Absolute Maximum
Anode Voltage (max)AC Voltage per Plate (max RMS, condenser input)375V
Rectifier
Peak Inverse VoltagePeak Inverse Voltage1,400V
Voltage Drop (typical)Voltage Drop (at 175 mA)23V
DC Output Current (max)DC Output Current (max)175mA
Notes
The Tung-Sol datasheet states: '5V4G and 83V are power rectifiers with low internal voltage drops. They are designed for service in AC operated receivers that require high currents. Their ratings and electrical characteristics are identical.' The 5V4G is the Octal-base version.
High-vacuum type — no warm-up delay required before applying B+ voltage, unlike the mercury-vapour type 83. Safe for immediate operation.
Indirectly heated with unipotential cathode — the 5V heater winding is isolated from the cathode, unlike directly heated rectifiers where the filament IS the cathode.
Voltage drop is approximately 23V at 175 mA (condenser input to filter). Higher than mercury-vapour 83 (~15V) but lower than many other vacuum rectifiers.
With choke input filter: max AC plate voltage increases to 500V RMS (vs 375V RMS with condenser input), same 175 mA DC output.
If filter condensers larger than 40 µF are used, additional plate supply impedance may be necessary.
TDSL confirms CV2547 as a close/identical substitute.
Pin Layout — UX4
1Anode 1 (Plate 1)
2Heater / Cathode common
3Anode 2 (Plate 2)
4Heater / Cathode common
Socket-Compatible Tubes ⚠ Not electrically compatible