@lzcontest/digital

Amateur-radio DSP and modem primitives for RTTY, PSK, and MFSK.

Install

npm install @lzcontest/digital

Encode text

import { encodeMfskVaricode } from '@lzcontest/digital/mfsk';
import { encodePskVaricode } from '@lzcontest/digital/psk';
import { encodeIta2 } from '@lzcontest/digital/rtty';

const rttyCodes = encodeIta2('CQ TEST').codes;
const pskBits = encodePskVaricode('CQ TEST').bits;
const mfskBits = encodeMfskVaricode('CQ TEST');

Analyze audio

import { createNormalizedSpectrum } from '@lzcontest/digital/spectrum';

const spectrum = createNormalizedSpectrum(
  new Float32Array(2_048),
  48_000,
  {
    startFrequencyHz: 300,
    binWidthHz: 10,
    binCount: 271,
    floorDb: -90,
  },
);

Entry points

| Import | Purpose | | --- | --- | | @lzcontest/digital | Complete public API | | @lzcontest/digital/rtty | ITA2, AFSK/PFSK, streaming RX/TX, and tuning data | | @lzcontest/digital/psk | BPSK/QPSK, Varicode, streaming RX/TX, and AFC | | @lzcontest/digital/mfsk | MFSK16, FEC, interleaving, Varicode, and streaming RX/TX | | @lzcontest/digital/spectrum | FFT spectrum normalization | | @lzcontest/digital/worklets | AudioWorklet-safe protocols and processors |

License

AGPL-3.0-only