There are lots of cheap test equipment modules on ebay and aliexpress, but it's hard to know much about their quality.
In many cases there have been reviews, mod suggestions, schematics etc. posted but these can be hard to find.
Does anyone know of a good resource for such documentation ?
Unless anyone does, I'm going to suggest we create one here. We can post links and I (or a helper) will update the thread start to keep an index. If it works out, perhaps we can get the thread pinned. This thread will do for test equipment - anything from an ESR meter to a nanoVNA - but other modules such as power supplies can have their own thread.
Note that this is an index, not a review site. It will link to other people's information wherever that is, it won't steal or copy it.