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Fldigi for Mac

A software modem for Amateur Radio use.

In English
Version 4.1.20
Based on 1 user rate

Fldigi overview

Fldigi (Fast Light Digital Modem Application), pronounced "F L digi", is a cross-platform modem program that supports most of the peer-to-peer (live keyboard) digital modes used on the amateur radio bands

Narrow Band Emergency Messaging System an integrated suite of programs that can be used for both emergency communications and recreational operations. The software is designed to run on nearly any modern computer and can be easily interfaced with almost any radio

What’s new in version 4.1.20

Version 4.1.20: Version 4.1.20:
Cosmetic changes:
  • Fix cosmetic issues reported by Bob, VK2YQA
  • Fix parse of macro
Gleam scheme:
  • add fltk 'gleam' UI scheme
xmlrpc id:
  • add client ID to client requests
  • add client ID to server parsing
cw tracking:
  • adjust tracking filter constants to improve power detection
Navtex modem:
  • make single bit flip correction guess a little smarter
  • The flip_smallest_bit code was written with the assumption that the discriminator has equal weights for mark and space, that we are equally likely to get things wrong in each direction, and that flipping the bit with the smallest absolute value is likely to get us what might have been transmitted.
  • However, in the face of selective fading and QRM, the assumption of symmetry proved to be wrong. This is "helped" by the 3/4 framing of SITOR-B, where every character has 3 marks and 4 spaces, resulting in the mark value consistently getting a lower envelope estimation than the space value, even when both are the exact same signal level!
  • Make the bit flip guessing a little smarter by correcting towards the 3/4 framing, but only if this character is only one off from a valid character.
  • This seems to result in slightly better message decoding in marginal circumstances.
Smeter Pwr_meter:
  • correction to xmlrpc procedure to get smeter and power out meter from flrig
My Callsign:
  • modify edit code to maintain cursor position
Contest fields:
  • Change to Rx text field parsing
  • Change to cut number parsing
gpio ptt:
  • fix for pi3/4 gpio h/w UDRC-II operation
Add OFDM modes for NBEMS:
OFDM-500F for HF SSB:
  • survives HF NVIS/long path
  • 4-carriers of 62.5-baud 4PSK = 250 bps
  • 1/2 rate K=15 FEC with 4sec interleaver
OFDM-750F for HF SSB:
  • survives HF NVIS/long path
  • 3-carriers of 125-baud 8PSK = 562 bps
  • 1/2 rate K=13 FEC with 3.2sec interleaver
OFDM-2000F for HF-SSB/FM:
  • 8 carriers of 125-baud 8PSK = 2000bps
  • 2/3 rate K=13 FEC with 3.2sec interleaver
OFDM-2000 for HF-SSB/FM:
  • 4 carriers of 250-baud 8PSK = 3000bps
  • NO FEC, meant for line-of-sight
OFDM-3500 for FM 9600-port:
  • 7 carriers of 250-baud 8PSK = 5250bps
  • NO FEC, meant for line-of-sight
  • Requires Signalink made-after 2018 connected to the 9600-jack
OFDM-2000F CPU-load fix:
  • FEC of previous mode too heavy for some CPUs
  • Reduced to: K=11 FEC with 1600msec interleaver
Other mode parameters unchanged:
  • Added Vestigial-carrier based AFC to OFDM modes
  • Increases robustness and tolerance to drift
OFDM 2000F hold:
  • commented out OFDM 2000 and 2000F modes for bugfixes
  • OFDM 500F, 750F, and 3500 are complete

Fldigi for Mac

In English
Version 4.1.20
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(1 Reviews of Fldigi)

  • Comments

  • User Ratings

Apr 3 2020
Apr 3 2020
Version: 4.1..11
fldigi is the "go-to" tool for multiple modes of digital communication available to Amateur Radio operators and shortwave listeners. It is frequently updated, and well-supported by the developer and knowledgeable users, on the "linuxham" forum at groups.io. fldigi and the other programs in the "fast light" suite are multi platform, with versions for various flavors of Linux, Windows and macOS. The developer's website also has user guides, as well as information on and sample sound files of many digital modes.
Apr 3 2020
Apr 3 2020
Version: null