If was hard to find it but here is it : one of the first EU/US version with A01 ROM.
This one is in a mint state. Lucky guy, isn’t it ?
On the front side nothing can distinguish it from the successors…
On the back no more difference. But if you look closely on the serial number there is a big difference : it begins by “20000…” and ends with 892. This one is in the first 1000 sold items. For the Japan version you will have to find a serial number beginning by “1”
Inside we see lot of blue wire straps. It happens sometimes in the early A03 versions.
Let’s look closely on the boards…
The CPU board has lot of errors. On the keyboard/display board you can see the SC613128 ROM IC with A01 on it.
Now we remove the board from the front side.
The display board revision is F2075
And we do same with the CPU board and see F2076.
I will soon make same with the other versions.
See Sharp Technical Reports for ROM differences :
And same with the printers because they have many revisions and at least 2 ROM versions