I'm sorry for diggin this up, but I wasn't exactly sure where it'd be the most suitable to ask while not creating a separate thread.
I've recently picked up 2 (two) "Panda Prince" cartridges with identical PCB's (NT-858/A9712) and unfortunately I can't get them to work on ANY kind of hardware I have (Twin Famicom, Pegasus famiclone, Ken-Kid Famiclone, Entertainment Computer System NESclone, First Austria NOAC and a shitty PolyStation NOAC famiclone). All I got is a blank screen... Believe me, I've tried EVERYTHING. PCB's looks intact, pins have been cleaned, all lines are fine, what is going on then? Do you have any ideas?
Spoiler: click to toggle
Is it possible that they both are dead? Isn't that just too much of a coincidently bad karma? :'(