The Transformer,audio Frequency, cataloged under National Stock Number 5950-01-138-1815, is classified within Federal Supply Class 5950 (Coils and Transformers) of the Electrical and Electronic Equipment Components group. The manufacturer of record is Magnetika Inc. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5950-01-138-1815 |
| Primary Part Number | BSB-531 |
| Item Name | Transformer,audio Frequency |
| FSC / FSG | 5950 / 59 — Coils and Transformers |
| Manufacturer | Magnetika Inc |
| Status | ACTIVE |
| Mounting Facility Quantity | 4 SINGLE GROUP |
| Inclosure Type | FULLY INCLOSED |
| Center to Center Distance Between Mounting Facilities Parallel to Length | 1.156 INCHES NOMINAL SINGLE MOUNTING FACILITY SINGLE CENTER GROUP IN |
| Mounting Method | THREADED HOLE(S) SINGLE GROUP |
| Body Width | 1.531 INCHES MAXIMUM IN |
| Body Height | 2.031 INCHES MAXIMUM IN |
| Maximum Transformer Power Rating | 30.0 MILLIWATTS SINGLE COMPONENT |
| Winding Function and Quantity | 2 PRIMARY AND 2 SECONDARY SINGLE COMPONENT |
| Impedance Rating in Ohms | 125.0 MINIMUM AND 150.0 MAXIMUM SINGLE COMPONENT ALL PRIMARY |
| Impedance Rating in Ohms | 125.0 MINIMUM AND 150.0 MAXIMUM SINGLE COMPONENT ALL SECONDARY |
| Winding Shielding Method | INTERNAL SHIELD GROUNDED TO CORE SINGLE COMPONENT |
| Nominal Thread Size | 0.112 INCHES SINGLE GROUP IN |
| Maximum Operating Temp | 105.0 CELSIUS DEGC |
| Body Length | 1.531 INCHES MAXIMUM IN |
| Reliability Indicator | NOT ESTABLISHED |
| Frequency Rating | 10.0 HERTZ MINIMUM AND 50.0 KILOHERTZ MAXIMUM SINGLE COMPONENT |
| Center to Center Distance Between Mounting Facilities Parallel to Width | 1.156 INCHES NOMINAL SINGLE MOUNTING FACILITY SINGLE CENTER GROUP IN |
| Terminal Type and Quantity | 13 WIRE HOOK |
| Thread Series Designator | UNF SINGLE GROUP |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| BSB-531 PRIMARY | Magnetika Inc (USA) |
| Reference | Meaning |
|---|---|
| BSB-531 | 5/9 Secondary reference U.S. Government activity |
NSN 5950-01-138-1815 is a Transformer,audio Frequency, manufactured by Magnetika Inc, classified under FSC 5950, Coils and Transformers. Status: active.
NSN 5950-01-138-1815 has 1 manufacturer part number on file: BSB-531 (Magnetika Inc).
Key specifications for BSB-531: Mounting Facility Quantity: 4 SINGLE GROUP; Inclosure Type: FULLY INCLOSED; Center to Center Distance Between Mounting Facilities Parallel to Length: 1.156 INCHES NOMINAL SINGLE MOUNTING FACILITY SINGLE CENTER GROUP IN; Mounting Method: THREADED HOLE(S) SINGLE GROUP. 19 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.