VALVE SOCKETS
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TECHNICAL ARCHIVE · VALVE SOCKETS
← Find a valve socketSylvania 1B46/1B47 polarised bayonet base, offset lugs
Mechanical data, images and references from the EnryLab archive.
Key specifications
- Reference code
- SYLVANIA-B15-STAGGERED
- Contact positions
- 2
Mechanical dimensions
All linear dimensions are in millimetres and describe the valve base and its pins. They are not socket-hole diameters.
The pin circle passes through the pin centres. Pin spacing is the straight-line distance between adjacent centres. ≈ denotes a value calculated from nominal geometry; ± denotes a tolerance, parentheses show limits and ≤ denotes a maximum.
| Dimension | Value (mm) | Detail |
|---|---|---|
| Valve base | ||
| Base-body diameter | ≤ 16.002 | Dimension shown in the drawingView detail |
| Lateral-pair centre spacing | 6.7818 | Dimension shown in the drawingView detail |
| Axial offset between bayonet pins | 3.175 | Dimension shown in the drawingView detail |
In depth
Sylvania 1B46 and 1B47 use a bayonet with two bottom contacts and side pins at different heights. This axial offset polarises insertion and is a decisive socket-identification feature.
The pin levels are separated by 3.175 mm and the bottom contacts by 6.7818 mm. Maximum base-shell diameter is 16.002 mm, whereas the 14.986 mm limit concerns the tube's upper envelope. These male dimensions remain separate from female-socket tolerances.
Two bottom contacts are insufficient to identify a bayonet with pins at the same height. The modern designation BAY15d is not assigned from resemblance alone; specifications and tolerances would need comparison. The offset remains explicit in the family description.
The height difference between the side pins prevents describing the shell as an ordinary symmetric bayonet. The bottom contacts remain separate from the retainer, while orientation determines which terminal reaches each opening.
In 1B46, the bottom connections are identified as anode and cathode; 1B47 retains its double-contact bayonet qualification. Upper-envelope and lower-cap dimensions must be distinguished when comparing valves or sockets.
Technical drawings
The drawings show orientation and geometry. Links beside the dimensions open the available detail.
Photos and examples
No photos are available for this socket yet.
Related valves in the archive
Total linked designations: 2