I'm doing some proactive maintenance on a vintage games console from the late 70s. There are a couple of linear regulators which I thought would be prudent to replace whilst I'm at it. Unfortunately the markings on one are nearly illegible and on the other are completely gone. (They were covered by some tape which took the markings off when I removed it)
I know the marked one is a LM78M12x - the 'x' is illegible. The other is a 5v regulator confirmed with a DMM. I have searched for schematics in vain.
The question is what suitable modern replacements should I use here? Are there any other clues I can look for which might help?
Can I cause any problems by choosing the wrong ones e.g. LM7805 instead of LM78M05? Should I go with a modern switch-mode version?