> Walt/K5YFW wrote: > So back to my question, I think you and I agree that MT63 and > MFSK16 are the answer to Bonnie's problem. > > So your figures are right in-line with what others found for > MT63. And of course MFSK16 is a wonderful keybaord-to-keyboard > mode even transmitting macros nicely. > > The choice seems clear to me.
Hi Walt, The discussion on HFLINK about HF ALE and digi keyboarding is revolving more around the need for setting some initial hand-off standards for a few of the most ubiquitous and useful ham texting digi methods. We have talked about standardising at 1500Hz center audio frequency whenever possible. There are several reasons, but mostly because it is near the centre of the ALE 8FSK channel, and near the centre of the normal SSB passband. The transfer from the initial ALE selcall linking over to the keyboarding can be assisted via a short "AMD orderwire" text message that appears on the ALE transceiver's screen or software ALE controller's computer display. For example, if the first operator simply sends an AMD text: "PSK" to the second operator, both operators would then already know to change over to BPSK31 at centre 1500Hz. So far, BPSK31 and Olivia 500/16 have been discussed. Of course, BPSK31 is a natural starting point because it has become rather ubiquitous among keyboarding hams these days. There are many PSK31 software programs for all different computer operating systems, and even a few BPSK hardware modems. Olivia 500/16 is probably one of the most robust digi keyboarding methods in use presently, so it is mainly attractive because it is many dB better than PSK31 for bad S/N conditions. But not as many hams have experience using Olivia yet, and the number of software programs is limited. As you mentioned, Walt, MT63 is another excellent digi that could be very useful for higher speed traffic when needed. The 2kHz bandwidth of MT63 is similiar to 8FSK ALE bandwidth, so it is a good fit when set to a centre audio frequency of 1500Hz. There are other loose standards for audio centre and mark frequency used by hams for various digi signals. 1000Hz has been used. For RTTY, about 2000+Hz has been used. For Olivia, a bottom frequency of 500+Hz has been used. Of course, having to remember all these different audio frequencies in the middle of operating the radio is often difficult for the operator, and it makes the transition from ALE to keyboarding digi less reliable. So, as I mentioned, the focus of the discussion so far is toward setting some hand-off standards to enable easy and robust keyboarding that is compatible with the most stations. Bonnie KQ6XA . ------------------------ Yahoo! Groups Sponsor --------------------~--> Yahoo! Groups gets a make over. See the new email design. http://us.click.yahoo.com/XISQkA/lOaOAA/yQLSAA/ELTolB/TM --------------------------------------------------------------------~-> Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
