Hi Jean Louis,

I did a couple of experiments here to see if I could reproduce the results 
described in your item 1. 

1. I transmitted a WSPR signal using WSJT-X 1.7 r7032 using my GPSDO-referenced 
TS-480 and received that signal using my Gnuradio/USRP1 SDR which is referenced 
to the same GPSDO. Received wav files were decoded using the wsprd from wsjt-x 
1.7. I did not find any significant frequency offset. 

Measured frequency was within 0.1 Hz of expected - the 0.1 Hz difference could 
be explained partly by TS-480 DDS resolution. I used the high resolution (0.1 
Hz) frequency estimates available in the ALL_WSPR.TXT file for this.

2. I compared the WSPR-estimated frequencies of off-the-air signals using my 
Gnuradio/USRP/GPSDO setup and the TS-480 with WSJT-X 1.7.0 r7032. Comparison of 
received frequencies shows no offset (at the 1 Hz resolution level). Offsets on 
the order of 0.1-0.2 Hz are present in the high resolution data — but this is 
not unexpected, especially on weak signals. The two rigs use different 
antennas, so the noise will not be perfectly correlated between the two 
receivers.

Is it possible that you had different settings in the 
Preferences/Frequencies/Frequency Calibration in your two instances of WSJT-X?

Steve k9an

 
> On Aug 14, 2016, at 10:04 AM, f5djl <[email protected]> wrote:
> 
> Hello all 
>  
> I am  still having a lot of fun with WSPR/WSJT-X and I am  getting prepared 
> for the new modes  but I have questions for you on our good old friend WSPR-2 
> J  : 
>  
> 1/I  have noticed a difference of behavior between 1.6.0 R 6263 and 1.7.0 r 
> 7005 both executable from Joe's site  , The difference is in the reported 
> frequency.   I hope the screen shot attached below will describe the problem 
> .Same  wspr2 signal generated by an instance of 1.7.0 is decoded by an 
> instance 1.6.0 and an another instance  1.7.0 , it produces different results 
> ( frequency difference 4 Hz)  and the frequency reported does not match the 
> one of the transmit side in case of 1.7 receive instance .   Is it a normal 
> behavior ? 
>  
> <image001.jpg>
>  
>  
> 2/ I also noticed that the Tune frequency is initially off frequency by 2Hz 
> in WSPR mode  , until you adjust manually the TX freq parameter then on 1500 
> Hz it is at 1500 ( variable initialization ?) ! 
>  
> Thanks in advance for your help to clarify  and this great wsjt-x piece of 
> code . 
>  
> Let me know if any further details are needed and very best regards from 
> France 
>  
> Jean Louis F5DJL
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