Just could not help : I sticked the TV coax adapter in the vice and took the hack saw to it... made two slits to begin with. No joy, still too stiff. 2 more slits then... that's 4 now.
Oh, it can go into the socket now, victory ! Requires some force and won't go 100% in, but almost. Good enough to get a signal on the scope ! Once you stop wiggling the adapter, the signal is pretty stable on the scope. Here testing at Fmax, 50MHz... and look at that beautiful, clean sine wave ! Not to mention signal amplitude, I get the full 100mV RMS that are dialed in, even though I got 30% less than that the other day when I was looking at the signal just by shoving my scope probe into the socket. 30% down was still within spec so I was happy.. but now I get 100% , no loss at all, so I am over the moon !
So it's definitely much better than before, so very happy I am. If I can find a better adapter with slits and softer metal, that will make a better contact, I am all for it. But for now my hack sawed cheap adapter is good enough for me, problem solved for now, I say.
I would have made a close-up picture of the screen to prove I am not lying about frequency and signal amplitude. Sadly just before doing that, I tried fiddling with the adapter to see if I could shove it in a bit more to make sure the trace does not go unstable right as I am trying to photograph it and... as I was grabbing the adapter, I got ZAPPED !!! Yes this generator tried to kill me !!!
So no close-up picture for you sorry... instead I immediately pulled the plug !
Checked with the DMM for resistance between the two line terminals in the power socket, and chassis/enclosure.... no short, got 5Mohms and slowly climbing.
So I am not touching this generator for now !
Think I will retrofit an IEC power socket hidden at the back (to not ruin the looks of the face plate), and get myself a life saving earth connection....
Will look at the schematic of the generator to see if there is maybe some failing cap that could explain the mishap...