Hello Andy, ALE 400 works as ALE. It can be found soundings, AMD, DTM and DBM messages which are the classical ALE protocols (AMD being the standard and DBM being the best one for exchange). They permits interconnexion of different hardware and software around standard protocols, which is the big force of ALE.
Now the ARQ FAE protocol derives directly from the DBM protocol, but integrating the best of the PAX protocol and the best of Pactor 1 (particularly the ARQ memory which comes to add a sur-code which permits to gain 3 dB at each repetition). This ARQ memory permits to put the S/N limit not on the message itself but on the detection of the preamble which houses the frame characteristics: once the preamble detected, the message will be decoded in all cases, after 0, 1, 2 or 3 repetitions. For detailed specifications of ARQ FAE: http://f6cte.free.fr/SPECIFICATIONS.ZIP 73 Patrick ----- Original Message ----- From: "Andy obrien" <[email protected]> To: "digitalradio" <[email protected]> Sent: Friday, May 29, 2009 1:56 AM Subject: [digitalradio] More on ALE 400 FAE > First, is it really ALE as used currently? I am not sure that the > recent tests of this "mode" have actually used it in the form of > establishing an automatic link. I know it can be used this way , but > do not see this. If it is not really ALE, what should it be called ? > > Second, the performance of ALE 400 FAE file transfers between Sholto > and myself last night was simply astonishing . Late at night (0400 > UTC) we passed a files east coast to west coast USA with audible > signal levels around S1 or less. 20 meters , I was on a vertical > running 90 watts. 100% copy (it is ARQ) in a fairly reasonable amount > of time with expected amounts of re-tries. So, regardless of whether > this mode is used in automatic link establishment , it really has to > be considered as a very reliable method of transferring short files > under very poor conditions and much longer files in good conditions. > Well done Patrick! > > > So, in addition to NBEBS ARQ MFSK16 and ARQ PSK, we now have and even > more robust mode that beats its way through the QRN and low sun spot > conditions. > > Andy K3UK > > > ------------------------------------ > > Announce your digital presence via our Interactive Sked Pages at > http://www.obriensweb.com/sked > > Recommended digital mode software: Winwarbler, FLDIGI, DM780, or Multipsk > Logging Software: DXKeeper or Ham Radio Deluxe. > > > > Yahoo! Groups Links > > > > >
