Well, the HP 85044A test set still has N-type ports.
And that pesky APC7...
Oh well...
Promised photos of connectors. I'd appreciate if someone knows their original HP/Agilent part-number.
I bought 4pcs. N-SMA on the right is original from 8753A.
Two connectors are decent shape, two other bit worse. But nothing too bad.
Close-up of inner collet:
"Air" isolator, clearly visible by backlit photo on the right. Of course it's not air in full meaning of the word, but most of gap space is empty, hold just by the transparent plastic spacer.
To actually install them into 8753A's frame, some metal work would be required, as new connectors have only one notch on threaded mount, while old N-SMA had two notches on both sides.
I'll just mill excessive metal on the frame with Proxxon
And everything would look somehow like this:
Why all this trouble? Here are macro of original N-type ports:
Probably not so bad as most VNA-nuts would say to me, but I don't like that crud and rust on collets and housings. And you can see dents on the front outer shell, likely due to physical drop impact. All GHz's will run away
Hopefully this would be enough to get something going, once I receive that 85044A. I'll get some cheapo N-SMA cables, and maybe APC7 to SMA or N adapter.