Hello to all, > has compression which can greatly increase speed The compressed alphabet derives from the "IZ8BLY MFSK Varicode". The main modifications are a priority given to accented small characters (much used in French, Spanish...). The gain is about 50 % in English.
- first sound card ARQ mode with the full ASCII character set: So as to be able to transmit accented characters and also non-latin characters (Cyrillic ones for example), - first sound card mode employing memory ARQ It's really indispensable for an ARQ protocol because it permits to drastically decrease the number of retries (each new frame retry is equivalent to an increase of 3 dB on the minimum S/N with a limit which is the impossibility to detect the header). > Maybe we can convince Patrick to look at possible "store and forward" > functions as well I have added to my wishes list the possibility to add an ARQ FAE repeater. I will see if it is possible (I'm not sure as it is quite complex). >Would it be possible to extend the KISS mode interface to other modes >and not only packet? I don't know right now, but sounds tempting. Seems also difficult (due to the translation of protocols), but another solution would be to use the TCP/IP link (RX/TX) and add a new protocol layer (not simple either). I could extend the functions from the TCP/IP control. 73 Patrick ----- Original Message ----- From: "Rick W" <mrf...@frontiernet.net> To: <digitalradio@yahoogroups.com> Sent: Friday, January 30, 2009 4:11 PM Subject: Re: [digitalradio] ALE400 and 141a > Hi John, > > At the time I was listening to the frequency there were RTTY stations on > either side and very close, so did not attempt a connection. > > Were you using ALE400 or FAE400? My understanding is that FAE is faster > than the ALE with plain text due to compression which I don't think is > available in ALE400. I have never quite understood the purpose of the > ALE modes unless perhaps it was used for a group (non ARQ) transmission. > But in such a case wouldn't you want to use a better mode than ALE which > is an older technology from the 1970's and developed before the advent > of sound card modes and computer access. > > When I have tried the wide 141A (ALE/FAE 2000) modes, they have not been > as practical to use for the conditions you normally find on the lower > bands. FAE2000 might work reasonably well on higher bands with low > ISI/Doppler. The speed is several times faster, but the bandwidth is > about 5 times wider and less robust. > > The reasons that I am so impressed with FAE400: > > - relatively narrow (keeping under 500 Hz) to meet the IARU band plan > bandwidths designated for the RTTY/Data portion of 80 meters > > - has compression which can greatly increase speed > > - first sound card ARQ mode with the full ASCII character set > > - first sound card mode employing memory ARQ > > The only other mode that may have some of these characteristics is > Winmor, but that has not been released yet. > > What has been surprising to me is that few hams have any interest in > using these connected modes, especially for public service/emergency use. > > 73, > > Rick, KV9U > > > > John Bradley wrote: >> >> After an evening of limited testing, VE6OG and I found ALE400 much >> better on a file transfer tonight, given the band conditions and >> >> QRM. >> >> >> >> Both stations remain on for the rest of the night and early morning . >> >> >> >> John >> >> VE5MU >> >> > > > ------------------------------------ > > Announce your digital presence via our Interactive Sked Page at > http://www.obriensweb.com/sked > > > > Yahoo! Groups Links > > > > >
