jks

Okay, a few things here. "I except the implementation of GPS in the KIWI needs a little more care than the QRP labs version and did hope the outside antenna would fix". Just so I understand: does this mean you were able to plug the same antenna/coax into the QRP Labs WSPR device and it received better than the Kiwi?

Your new image above looks fine actually. RSSI in the 1200-1500s for Galileo is pretty normal. The GPS RSSIs are a little low. What concerns me is the shadow map. It's only been a 6 hour run, but it's clear you only see sats above 45 deg elevation. Worse, because you're at 51 deg latitude the GPS polar "hole" is coming into effect and that is limiting what you get above the W-E line. So your actual sky view is smaller than I thought.

But having only 212 fixes over a 6 hour period is terrible. Another issue is that when you limit your sky view to one area like this you have high "dilution of precision" (GDOP, https://en.wikipedia.org/wiki/Dilution_of_precision_(navigation)). This will cause the time/positions to be less precise and they may be so far off that they get filtered out.

Your latest shadow map has the classic shape described in this post: http://forum.kiwisdr.com/discussion/1083/gps-antenna-aiming

Until the 180 degree meridian bug is fixed position your Kiwi map so the 180 meridian (longitude) line is off the right side of the map. That line it located slightly to the right of New Zealand. It doesn't matter if your Kiwi doesn't show in the map after it has been selected.

@Ron, That image shows IQ mode, but with a center frequency of 59.5 kHz and an unbalanced passband that is much too wide for running TDoA on WWVB. If you actually ran using these settings try running again on exactly 60 kHz with a balanced passband of, say, 100 Hz. Hold down the shift key and then click the +/- magnifying glass icons (zoom icons) to symmetrically adjust the passband. Each time you click the passband is reduced (increased) by 80%. Hover over the left or right yellow passband edge to see the current bandwidth.

Sorry everyone, I am compiling all your ideas and suggestions. But I can't reply in detail because I'm drowning in emails and posts and there's hardly any time to get real work done.

@daniel I have not had time to get linkz's directTDoA project running on my laptop. I've just looked at his screenshots. I also still need to integrate Christoph's latest code which includes the likely solution center marker.