Overview
The Ohmite B12J50R is a heavy-duty wirewound ceramic resistor rated for 12 watts at 50 ohms. Supplied as a bulk box of 25 units, this resistor features robust axial leads and a vitreous enamel coating designed for reliable performance in high-temperature industrial environments. Ohmite’s “Brown Devil” 200 Series represents decades of proven power resistor engineering, making it an excellent choice for telecommunications, RF impedance matching, and energy harvesting applications.
Key Features
- 12W Power Rating: Wirewound construction with flame retardant coating
- Precise Resistance: 50Ω ±5% tolerance
- High Voltage Rated: 625V voltage rating
- Rugged Construction: High temperature vitreous enamel coating, flame resistant, all-welded construction
- Axial Leads: Axial leads for standard board mounting
- Temperature Coefficient: ±260ppm/°C
Technical Specifications
These resistors are engineered for applications where stable impedance and high reliability are non-negotiable. All-welded construction ensures minimal failure risk under continuous thermal cycling, while the ceramic core provides excellent heat dissipation for sustained operation.
Typical Applications
- RF and microwave impedance matching networks
- Tuning and load circuits in broadcast equipment
- High-power test and measurement systems
- Industrial frequency converters and power supplies
- Telecommunications and signal distribution
- Dummy loads and power absorption circuits
Compatibility & Replacements
Compatible With
- Printed circuit boards with 0.1″ pitch axial lead spacing
- Breadboard and prototype layouts using standard through-hole footprints
- Potted and conformal-coated assemblies (ceramic core is solvent-resistant)
- Any circuit requiring a stable 50Ω impedance reference
Replaces / Drop-In Replacement For
The B12J50R is a direct replacement for other Ohmite 200 Series 12W 50Ω wirewound models. Verify compatibility with your system integrator before ordering to confirm mechanical and electrical fit for legacy designs.
Works With
- RF network analyzers and impedance measurement equipment
- Power supply design and prototyping tools
- Standard soldering and assembly processes (RoHS-compliant)
- Thermal imaging during high-power testing (visible ceramic body)














