Here’s oldie TS9 from my private stash.
As you see on pictures it was made 1984, S/N starting at 4, and most electrolytic caps with date codes starts on 84XX makes me to think that.
There is no date codes or brand on the pots.
Battery cover and board are marked MAXON, IC chip is hated TA75558P, but I don’t really give a fuck about JRC mojo rave…
Diodes have legendary blue stripe, back plate is silver “pre CE” type. This and the rest is nicely visible on the picts attached..