the the the the the and allow .... Must learn to check before hitting 'send' ! Andy www.g4jnt.com
--- In digitalradio@yahoogroups.com, "ac.tal...@..." <ac.tal...@...> wrote: > > You'll probably find JT65C is needed on the UHF bands, 432 to 2.3GHz for > example, to allwo for teh frequency spreading Doppler - abnd certainly for > EME for which it was designed. > > Conversely, at LF, 137 / 503kHz, teh A varient is satisfactory and only > consumes half teh bandwidth. > > Andy > www.g4jnt.com > > --- In digitalradio@yahoogroups.com, "Andrew O'Brien" <k3ukandy@> wrote: > > > > While addressing an ARRL LOTW uploading issue with JT65 modes, I began to > > be intrigued about B and C that I have never tried . Here is an old 2004 > > explanation from Joe Taylor. Interesting ,at that time , that he was > > suggesting JT65B be the standard > > > > > > > > Mode Spacing Total BW > > ------------------------- > > JT65A 2.7 Hz 177.6 Hz > > JT65B 5.4 355.3 > > JT65C 10.8 710.6 > > > > Note that JT65A is identical to the original JT65. If you want to work > > people who have not yet upgraded to v4.3.3, be sure to select mode JT65A. > > Otherwise, be sure to use the same mode that your QSO partner is using. > > Cross-mode contacts will not work. > > > > JT65B should be nearly as sensitive as JT65A, and it will be twice as > > forgiving of frequency instabilities. On balance, with existing "stock" > > radios, JT65B will probably be better than JT65A. JT65C is less sensitive > > by a small amount, perhaps 1 dB, but will be even more lenient on stability > > issues. By all means experiment with the different submodes, and be sure > > to let me know your conclusions about them! > > > > I am presently inclined to recommend that JT65B should become the > > "standard" JT65 mode. If this tentative conclusion holds up, future > > versions of the program may no longer support the A and C modes. > > >
