Rattlegram - SMS via audio!

aicodix GmbH

About this app

COFDMTV is based on COFDM (coded orthogonal frequency-division multiplexing) technology:
- 160 ms long OFDM symbols
- 6.25 Hz per sub-carrier
- 1/8 guard interval
- differentially encoded PSK (phase-shift keying) modulation
- systematic polar codes for forward error correction

Currently Modes 14, 15 and 16 are supported:
Using either SPC(2048, 1392), SPC(2048, 1056) or SPC(2048, 712) with CRC32C aided SCL decoding and differential QPSK modulation for the payload.
Only a bandwidth of 1600 Hz is needed and the transmission of either 85, 128 or 170 bytes take about one second with the leading noise and fancy header disabled.

Ratings and reviews

If the creator can improve the interface more and add a 'clear messages button, save messages to folder button, and other better chat features I would definitely pay a good amount for an upgrade like that..... I use SSTV to send pics and maps/gps data and If you could incorporate a feature like that into this app too, I would pay big money for that. Please consider expanding the app like this! Thanks!!! Excellent work 👍

Excellent method for texts using analog transceivers and an Android phone like an old J3 Eclipse with this app installed. No internet needed, after you download this app.

Works well on simplex. Hit or miss on repeaters. Wish it had a level meter so I knew if I had enough volume level to get a good copy. Parrot feature is nice too. It is a good feedback that the message got through.

What's new

- improved robustness
- updated libs and tools