A had an SWR issue with my freshly built QMX+ which uses the exact same T507 as the QMX. I had wound both binocular windings in the same sense, i.e. both counter clockwise. When I noticed the SWR problem, I realised this and considering the SWR measurement to be a 'bridge type' I'd figured out, that both windings had to be each other's mirror image. In other words: one winding counter clockwise and the other clockwise, as described in the document quoted by Robert KD9YUY.
I unmounted T507 and rewound it the 'proper way'.
Result: no difference whatsoever! So apparently, the winding sense does not matter.
At the end, the problem was a poor solder connection of the 0.60 mm (AWG #22) wire...
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