Hi Meits!
Inside the box, when you open the cover in the backside.
Hurray... Found mine... Always tricky, disassembling those FM-PACs with those springs... And with that RCA output mine even has...
There is an easy way to find an FM-Pac SW-M004 serial number , look on the inside of the original box!
I have two of them in its original box..
#1 : 8KCSA41841
#2 : 8KCSA37356
Thanks
Music Module nms 1205 : HK 005739
Philips NMS8245/00 Nr.JM007 28030588
Hello! This was my first computer : Goldstar fc-200 Nr: FA5O0132 Manufacture date 85.10
VG8020/00 Nr.FF05 605013560
NMS 1205 HK 014410
SONY MOS-1 1-550-246-11
NMS8255/00: FF007 39020480
Panasonic FS-JM1 Mouse: 2277840
Updated again... Keep 'em coming. I can't believe there are more tubo Rs than the lower models...
Me too Meits.