Re: LF: 500 kHz JT4A

[Roger Lapthorn <rogerlapthorn@gmail.com>]

This is a mode I shall have to try next! I did not get any decodes earlier in the week when I tried, so I need to experiment to see what has to be adjusted. 

BTW, my WSPR beacon will not be on overnight tonight.

73s
Roger G3XBM

2010/1/22 Gary - G4WGT <g4wgt@tiscali.co.uk>

Rik,

Thanks for the report & pleased you are getting decodes now.

If you click the mouse on the "Tol" setting box. left click down, right click up, take it down & click freeze, that will freeze the decode bandwidth to a narrower bandpass. But don't forget to click on the wanted signal first. That will exclude any signal from outside that "Tol" setting indicated by the red marker line on the scale at the top.

Read the manual Rik, it seems a bit complicated but you will soon catch on :-))

73,  Gary - G4WGT.

2010/1/22 Rik Strobbe <Rik.Strobbe@fys.kuleuven.be>

Gary,

OK, I just decoded you (see previous mail).
But signals are that strong that CW would be armchair copy.
I guess I have to figure out the sync problem (as I understand a good value would be 20 or more).
Inituitive I assume that tuning into a signal is done by clicking on the trace, but even if I click on your signal (and see a marker on your freq.) most of the time it is still decoding Jim.
Another odd thing: when I decode you you get the same "dB" value (-2) as Jim, while Jim's signal is a lot stronger.

73, Rik  ON7YD - OR7T

Quoting Gary - G4WGT <g4wgt@tiscali.co.uk>:

Rik,

That will be me on 503.600 kHz. I will put the power up a bit.

73,  Gary - G4WGT

2010/1/22 Rik Strobbe  <Rik.Strobbe@fys.kuleuven.be<mailto:Rik.Strobbe@fys.kuleuven.be>>

As said I haven't read any instructions / manual but maybe the  figures WSJT7 spits out on the readable copies of Jim may give a clue:
Sync = 9
dB = -2
DT = 0.0
DF = -107
W = 33

73, Rik  ON7YD - OR7T

Quoting Rik Strobbe  <Rik.Strobbe@fys.kuleuven.be<mailto:Rik.Strobbe@fys.kuleuven.be>>:

Hello Gary, Jim,

I just fired up WSJT7 in JT4A mode.
I can see a very fat trace at 503.460 that decodes as "TEST M0BMU" and
a little less fat trace at 503.600 that is probably Gary. But even if
I set the marker on 503.600 (1300Hz audio) I still keep decoding "TEST
M0BMU".
It is my first test with JT4A and I haven't read the instructions /
manual, so it is intuitive use.

73, Rik  ON7YD - OR7T

PS: both signals are clearly audible (Jim is S7)

Quoting Gary - G4WGT <g4wgt@tiscali.co.uk<mailto:g4wgt@tiscali.co.uk>>:

LF,

I will be beaconing WSJT JT4A again this evening & I would welcome
any decodes, I have made changes in view of not decoding a reply
last night. I just need to confirm my outgoing signal before
changing Tx operation to CQ calls.

502.300 kHz USB dial frequency. Tx 503.600 kHz on even minutes.

73,

Gary - G4WGT.

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