Let me play devil's advocate. Regarding HF JT65A operation in practice in the presence of the usual atmospherics.
If I can't hear a signal, chances are near zero that it will be found tuning about the band by looking at the waterfalls. One almost needs to sked such "difficult paths". You have to know he's going to be there before looking. OK but much different from the normal HF mentality of tuning for random QSO's. So you have to depend upon the other guy hearing/seeing your CQ to establish one of these random marginal QSO's. But all things being equal, he likewise won't find you at random for the same reasons. I was just wondering how many of these random really weak signal contacts actually occur on HF. Like I said in my case it has been zero. 73 de Brian/K3KO --- In digitalradio@yahoogroups.com, "Andrew O'Brien" <[EMAIL PROTECTED]> wrote: > > All good comments. I agree with Danny AND Rick. I think I can safely say > that this group is responsible for the sudden explosion of JT65A activity on > HF, remember it is just one month old as a common HF mode. > > I'm perplexed too, I can find JT65A activity almost 24 hours per day but > rarely hear ALE and Olivia these days. I hear Hell and MFSK16 but not as > much as JT65A, by a big margin. > > As Danny correctly identified , JT65A, is simply amazing for extra weak > signal detection. Actually, I am not sure if it's the mode or just the WSJT > software, maybe the combination. I think however, that if someone like > Patrick developed software that would perform Olivia , ALE, DominoEx, etc , > etc...in the same manner as WSJT, hams would use it . Thus, I think we have > found that many hams enjoy a software product that enables precisely timed > "beacons" with simple responses to validate reception and a legitimate > exchange. > > In summary, JT65AWSJT performs well under weak conditions and the timing > divisions are attractive to experimenting hams. Give the same ability to > Olivia and Dominoex, easily, and I am sure use of those modes would > increase. > > > Andy K3UK > > On 5/30/07, Danny Douglas <[EMAIL PROTECTED]> wrote: > > > > The excitement of using the JT65 program on HF is NOT for those signals > > you > > can clearly hear and probably operate with another mode, but for those > > times > > that the propagation shows not to be there, you dont hear anything but > > possibly a slight raise in static on a band, etc. Then you can put this > > mode up, leave it alone, and see what pops out. Its for "playing" not > > really trying to communicate. FYI if anyone in P5 wants to work it, plse > > do so. Whether we can hear you or not, we will be there. > > > > Danny Douglas N7DC > > ex WN5QMX ET2US WA5UKR ET3USA > > SV0WPP VS6DD N7DC/YV5 G5CTB all > > DX 2-6 years each > > . > > QSL LOTW-buro- direct > > As courtesy I upload to eQSL but if you > > use that - also pls upload to LOTW > > or hard card. > > > > moderator [EMAIL PROTECTED] <digital_modes%40yahoogroups.com> > > moderator http://groups.yahoo.com/group/DXandTalk > > ----- Original Message ----- > > From: "Rick" <[EMAIL PROTECTED] <mrfarm%40frontiernet.net>> > > To: <digitalradio@yahoogroups.com <digitalradio%40yahoogroups.com>> > > Sent: Thursday, May 31, 2007 8:58 AM > > Subject: Re: [digitalradio] JT65A HF query/observations > > > > > I too have been perplexed why these modes that were developed for weak > > > signals on VHF and above and only have the most meager rudimentary > > > exchange, would have any value on HF, relative to already existing weak > > > signal modes. Perhaps because it seemed "new," some focused on trying it > > > out? > > > > > > What I still would like to see is a sound card ARQ modes that is > > > scaleable in speed and also can work with weak signals, QSB, etc. > > > > > > 73, > > > > > > Rick, KV9U > > > > > > > > > > > > Brian A wrote: > > > > I've been playing around with this on 20M. > > > > > > > > The new version which does the decoding starting at 48 seconds is a > > > > big help. > > > > > > > > Of the the 25 contacts I've made all were clearly audible. All could > > > > have been worked on CW with no difficulty. They could have been > > > > worked on PSK or other such modes too--much more quickly. Most came > > > > from answers to my CQ's. > > > > > > > > Is this the experience of others? > > > > > > > > So what is the benefit on HF? > > > > > > > > I clearly don't see this as being the future of HF ham radio. It > > > > isn't the killer ap. (I'm sure the MS, moonbounce and VHF capabilities > > > > are great and that was the original design objective) > > > > > > > > I'm a bit perplexed that stations which are S6 and above show up at > > > > -6db or so on the display. I know what it is editing. It is a pretty > > > > useless number to most users. What I want to know is: "how far below > > > > the current noise floor is the signal that I'm now working". It would > > > > seem that such a "below the noise" number could be determined and > > > > editied. Isn't this what all users (HF and V/UHF) want to know? > > > > > > > > 73 de Brian/K3KO > > > > > > > > > > > > > > > > > > > > Announce your digital presence via our Interactive Sked Page at > > > http://www.obriensweb.com/drsked/drsked.php > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > -- > > > No virus found in this incoming message. > > > Checked by AVG Free Edition. > > > Version: 7.5.472 / Virus Database: 269.8.3/824 - Release Date: 5/29/2007 > > 1:01 PM > > > > > > > > > > > > >
