5943011101 - Fair-Rite Mix 43 ferrite toroidal core – 5943011101 (FT-290-43)

The Fair-Rite Mix 43 5943011101 (FT-290-43) ferrite toroidal core is designed for broadband RF applications requiring magnetic stability, low loss, and controlled permeability. Mix 43 is widely used for baluns, RF chokes, EMI/RFI suppression (20–250 MHz), and RF transformers.

Thanks to its magnetic properties, it performs excellently in the HF range, with an ideal operating window between 0.5 and 10 MHz and extended usability up to 25 MHz for broadband transformers and baluns. It handles induced currents efficiently and offers predictable behavior, making it suitable for professional RF designers, radio amateurs, and advanced hobbyists.

Main Features

• Material: Fair-Rite Mix 43 Ferrite
• Toroidal geometry for optimal flux containment and EMI reduction
• Initial permeability: μi ≈ 800
• Optimized for EMI/RFI suppression 20–250 MHz
• Ideal for RF baluns and transformers in 0.5–25 MHz (best performance below 10 MHz)
• Excellent behavior in RF broadband circuits
• Stable performance across wide temperature ranges
• Original Fair-Rite component meeting international standards
• High parameter repeatability for production and prototyping

Typical Applications

• Baluns 1:1, 1:4, 1:9 for HF antennas
• Common-mode chokes for amateur radio
• EMI/RFI filters for 20–250 MHz
• Broadband RF transformers (0.5–25 MHz)
• Noise suppression on signal lines and RF cables
• Educational projects, RF kits, and prototyping
• Improving signal-to-noise ratio in radio systems

Advantages in RF Applications

• High attenuation of unwanted currents
• Noise reduction on power and signal lines
• Improved efficiency in filters and impedance-matching networks
• Good linearity in HF transformers
• Stable parameters under temperature variations

Why Choose Mix 43

The Mix 43 ferrite is versatile, covering EMI/RFI suppression from 20–250 MHz and RF transformer/balun applications from 0.5–25 MHz. It is optimized for RF chokes, broadband transformers, and HF amateur radio applications.