These are the go-to cores for EFHW 1:49 type Broadband Transformers or Auto Transformers for 80m-10m End Feed Half Wave (EFHW) Antennas. Or, 80-10m Common Mode Chokes. Toroidal cores are used in a wide variety of applications such as power input filters, ground- fault interrupters, common- mode filters and in pulse and broadband transformers. Dimensions 61.00mm Wide 12.70mm Thick 35.55mm Hole
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