JTDX vs. WSJT-X

For a long time, I've been wondering whether JTDX has fallen behind WSJT-X in its sensitivity to WSPR signals.

For some reason, I never simply saved a set of receive runs and worked out the numbers.

So, this morning, that's exactly what I set out to do.

Reception was carried out at 14MHz using a Yaesu FT-450, in a stable operating temperature, having run continuously over the past 36 hours.  Recordings of the time slots were made, and then played back for decoding 'offline' by each software.

Number of 2-minute time slots: 21 (42 minutes total data gathering)

Time of recordings, including gaps between switchovers/other activities: 07:18UT - 08:20UT.

Recordings made using JTDX v2.0.2-rc139 (Release Candidate) as the receiving software:

JTDX decodes: 97
WSJT-X decodes: 105

Recordings made using WSJT-X General Release 2.1.0 as the receiving software:

JTDX decodes: 104
WSJT-X decodes: 117

Combined spots for all runs:

JTDX total spots: 201
WSJT-X total spots: 222

Only in one time slot (07:38UT) out of 21 did JTDX decode (one spot) more than WSJT-X.

A check was made that 'live' decodes were no different to decodes from saved recordings.  There were no such differences.

So, the firm conclusion is that WSJT-X is 10.4% better than JTDX, at least in their current forms, accepting that both softwares are in continuous development, and that the JTDX version used is a RC, not a General Release version.  Importantly, JTDX developers have tended to focus on FT8-based HF DXing aspects of their software over the past months, whereas WSJT-X WSPR performance has been improved - clearly rather successfully.

It's likely that, at different times of the day, notably into the later evening at present, when most signals are weak at 14MHz, WSJT-X will prove to outperform JTDX by a wider, possibly much wider margin.  More on that as data is gathered...