HzDrop

Ready

Send

0 bytes · —

Receive

Received text appears here

Text or file

Waiting

Signal & packet details

Spectrum

Audio inactive
02 kHz4 kHz6 kHz8 kHz

Microphone input while listening; generated signal while sending. The chart runs only while this panel is open.

Sending Ready

Choose a profile and enter a message.

Receiving Not listening

Waiting for a valid packet header. All six profiles are detected automatically.

No packet yet—

Up to 4 transfers are retained in this tab. Resend the same content to fill gaps; reloading clears retained chunks.

How it works

Chirps locate each packet. OFDM sends bytes on many tones using differential phase (DBPSK or DQPSK). Reed–Solomon repairs errors; CRC-16 checks the header and CRC-32 checks the payload. Large transfers add 4 repair packets per 8 data packets and an 8-byte SHA-256 whole-transfer check. Content is not released until verified.

Microphone
Not opened
Input level
—
Screen lock
Inactive

Keep both devices close and their pages visible.