i am looking for the electronic diagram of the monitor "IBM CGA model 5153002", it is the old IBM CGA monitor for 220v CA.

Maybe in others countries have the same chasis but only changes the PSU for 110v.


I am trying to adapt this monitor for my MSX.

I already have perfect sync, after of to adapt the NEGATIVE phase 1vpap of the MSX, to POSITIVE phase TTL level sync. Really very easy to do that.

I also removed the TTL chips (2x IC 74S05), and connected the RGB of the MSX directly after of the removed TTL chips, (i means directly to the BASE of the transistors of the RGB amplifiers.

But there is a problem, the msx have RGB 1vpap output.

At the base of the transistors i needs 5vpap.

But without any convertion it works anyway, but not have the constrast enought (offcourse).

But there is other thing that makes me crazy.

if i set COLOR 15,1,1, i get a B/W picture perfect!, well, maybe the BLACK is a bit gray (like having the bright control a bit high).

but if i set COLOR 15,4,4 i get , blue background, but yellow letters.

i already set the black level balance, and both gain controls. I wonders why it does that... so i thinks there is a interaction between R, G and B or something that i am forgettin.

So to get a good picture of the problem i need urgently the diagram.

Somebody can helpme?...

PD: is my only one way to have a msx workstation again.

more details about what i does untill here is at

http://usuarios.arnet.com.ar/flyguille/monitor.doc (spanish with draws).