31A3
31A3 is also designated UY41.
Description
The 31A3 is an indirectly heated half-wave rectifier with a coated unipotential cathode and a glass bulb. It has an E8-30 base.
Ratings
The heater is rated at 31 volts and 0.1 amps. The maximum peak voltage between heater and cathode is 550 volts.
Physical Characteristics
The tube has a maximum overall length of 2-5/8 inches (67 mm), a maximum seated height of 2-3/8 inches (60 mm), and a maximum diameter of 7/8 inch (22 mm).
Base Connections
Pin 1 is the heater, pin 2 is the plate, pin 7 is the cathode, and pin 8 is the heater. Pins 3, 4, 5, and 6 are internal connections.
| Designation | Evidence | Confidence |
|---|---|---|
| UY41 | 44 independent documents | confirmed |
Equivalence is asserted only where the archive's own literature states it directly, in at least 40 separate documents. Tubes that merely substitute in some circuits are not listed here.
Original manufacturer datasheets for 31A3, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Philips | 31A3 | PDF (101 KB) |
| Philips | UY41 | PDF (235 KB) |
| Philips | UY41 | PDF (171 KB) |
Documents held here and used to write this page.
- UY 41 Half-wave rectifying valve (filed under UY41)
- TUBE TYPE 31A3
2 further designations appear alongside 31A3 in the literature but below the evidence threshold used here, so they are not listed as equivalent.