The low-power radio reference, built by homebrewers.

Calculators, core data, and build notes for homebrew QRP operators.

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Tools & Calculators

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Tool. Gain, noise figure, IIP3, MDS and dynamic range of a receiver chain.

Tool. L, Pi and Tee networks for real or complex loads.

Reference. Where QRPers gather, 160 m to 2 m.

Reference. Every iron powder and ferrite core in the calculators.

Tool. Butterworth and Chebyshev low-pass and high-pass filters.

Tool. Fair-Rite toroids (43, 61) and BN-61 binoculars.

Tool. Turns for a target inductance.