Hi! I'd just like to know that how hard is it to repair or replace the built-in disk drive in this computer? I'm asking this because i am planning to buy two on these machines and neither of them reads the disk properly, or so i've been told. What is the most common problem with these drives anyway? The drive belt?

that drive has no belt... most common problem is the original drive being single-sided.

An original 8235 drive DOES have a belt, so it could be just the belt. Problem is indeed that it is single-sided and so quite useless for almost all commercial MSX2 software.

I somehow remembered that these drives are single sided. I gues that the seller doesn't know that either and the drives might actually work, but he only has double sided disks. Are these drives easy to replace with DD drives? What kind of drive must the replacement be? I have old PC and Amiga drives stored somewhere.

I guess PC drives would work idd... They do for most other MSX models. You prolly would have to fit a new diskrom though...

Sonic's right there... Ask repairbas for a diskrom... If I'm not mistaken, he has DD drives in stock as well...

I thought the VG8235 required some more modification than just replacing the drive and diskrom.

As far as I remember (might be wrong), it's just the diskrom... But Bas knows all...

You have to change the diskrom, the drive cable, a little modification on the main-board and the best is to to change the power supply.
Old drives work on 12 v and 5 volt, the new ones only on 5 volt, so if the the drive is working you can see it on the screen.

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You have to change the diskrom, the drive cable, a little modification on the main-board and the best is to to change the power supply. Old drives work on 12 v and 5 volt, the new ones only on 5 volt, so if the the drive is working you can see it on the screen.

Sounds a bit too complicated for me as my soldering skills are close to nothing and i only seem to have old HD-drives taken from PC's right now. Getting a new power supply would probably be quite hard too. But, this doesn't really matter as i mainly use MSX machines to play cart games, so i don't really need a disk drive anyway. Is it possible to use an external disk drive with this thing or will the built-in controller screw it up?

You can use a external drive without problems. Only the drive-letters can get mixed up.

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You have to change the diskrom, the drive cable, a little modification on the main-board and the best is to to change the power supply.

Sorry to bring up an old topic, but I own another VG-8235/00 that is fitted with a modern PC floppy drive but only 360K capacity. I have downloaded a Disk ROM image and burned a new EPROM. When I tried to format a floppy double-sided, Basic said "Bad parameter". After disassembling the computer, I found the floppy drive cable was assembled to fit a NMS 8245 instead of a VG 8235.

I found a guide by HansO 2003 which I believe strives to support 720K floppy drives. It mentions 2-3 wires should be connected to LF58, LF65 and LF61 in order to work on the 8235. Is this what you refer to "a little modification on the mainboard"? If so, could anyone explain which end of the three pin capacitors (?) I should solder the wires to? As the cable was wired, the side select pin was going to pin #8 (side select on the 8245, but drive select 2 on the 8235), and ditto for the "in use/open" pin.

I have a 8235/00 too. Actually, drive is changed and diskrom too.
If you do not want to bother with soldering, there is an easy sollution. Just plug a standard 34-pin cable in the "external drive" connector in the back (i passed it bellow the mainboard to where the drive is) and connect to PC drive. Maybe you will need to swap cables 10 and 12 (drive select 0 and 1).
If you do not get atched diskrom, try with poke -609,201, it helps a lot...
I did not use extra voltage regulators also, as 8235/00 power supply is enough if you use only one drive (i was able to connect 2 indeed!).

By the way, do not forget to fix the mapper as it is indicated in the technical manual. This way you will get -true- 128K.

What a horrible schematic is that. Where do you fint that little adapter-print?
Rewire the drive-cable.
Oeioeivogeltje discribed how I change that cable with any extra parts (and ofcourse costs)

Notice that 8235/00 is a very special model. Drive connector is not "exactly" the same than 8245.
8235/20 and others have a very different board. Sollution for them and 8245 is not the same.
For more info on connectors, try http://msx.retro8bits.com/msxdocs/vg8235sm00.pdf and http://msx.retro8bits.com/msxmanuals.html