Did the engineers that made those designs wanted to go public? Yes, No?
The opinion of the engineers doesn't matter, it's their employer that matters. I find it very unlikely that Uni-T intended these documents to be released if it's not on their own website.
As far I am aware of, any one who had contacted UNI-T by email asking for help.
He ended up with a technical document given by the UNI-T support personal,
with explanations of how to repair the DMM by your self !!
That's nice. It also saves them the costs of actually repairing it, just outsource repairs to your customers.
Fluke was doing the same about offering all the service manuals in PDF.
But they changed this tactic before few years. ( speaking about the latest DMM )
They usually combine the service manual with calibration manual these days. For what model do they fail to provide one? Of course the service manuals published these days are useless compared to the old ones with full schematics, since they usually only contain basic troubleshooting and mechanical parts, but that's an industry-wide practice. The fact that some schematics were leaked (I believe there are also leaked version of some Fluke schematics floating around) doesn't change this, unfortunately.
yes its wise, 100%!
Exactly. Web hosts love their users being involved in illegal activity. They usually give their customers plenty of opportunity to respond when they're notified about the copyright infringement. For the irony-impaired: providers usually yank websites without any warning if they suspect illegal activity.