HzDrop
Ready
Send
Receive
Received text appears here
Message history
Signal & packet details
Spectrum
Audio inactive02 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 profiles are detected automatically.
Data appears as it arrives. A red border means SHA-256 verification failed. Resend the whole transfer if needed.
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 use full-size data packets followed by a SHA-256 verification packet. Received text stays visible even if verification fails; a red border marks a mismatch.
- Microphone
- Not opened
- Input level
- —
- Screen lock
- Inactive
Keep both devices close and their pages visible.