Thomson 4120 Monitor cable for Amiga?

[RadRacer203]

So I'm going to be trading for an Amiga 2000 hopefully this week, and I just bought a Thomson 4120 monitor to go with it. Unfortunately it doesn't have the cable. I've never had an Amiga before but from what I can tell the 2000 has a db25 connector for video or something along those lines? This Thomson has a standard db9 plug although I don't know the pinout yet. Does anyone know what cables or adapters I need to hook this monitor up to the Amiga?

 

[RadRacer203]

I couldn't find a manual for the 4120, but I did find the manual for the CM 36512 VI with the pinout, and I'd be willing to bet the pinout of the 4120 is the same. Should I just build my own cable or would the cable for Commodore monitors be compatible?

 

[VERAULT]

So other than there being NO information on the internet about the 4120, it uses the same (seemingly European) long power switch in the commodore monitors [absurdly large switch even for the 1980s] which are impossible to source anymore. Why did these companies use these power switches?

 

[rager69]

I have the manual and it shows the pinout for analog mode and digital mode.

RGBI
1 - Chassis Ground
2 - Chassis Ground
3 - Red
4 - Green
5 - Blue
6 - Intensity
7 - Reserved
8 - Horizontal Sync
9 - Vertical Sync

RGB Analog
1 - Chassis Ground
2 - Chassis Ground
3 - Red
4 - Green
5 - Blue
6 - Reserved
7 - Composite Sync
8 - Reserved
9 - Reserved

It looks like the RBGI implementation is compatible with CGA (the manual shows a drawing labeled IBM PC). It looks like you can make a cable to make the Apple IIgs work with this, as well. It also looks like the Analog RGB implementation is similar to the Commodore 1084 9 pin, except those "Reserved" pins seem to have actual names on the 1084.

The switch in the front has four positions:

1 - Display analog RGB (4096 colors)
2 - Dispay green screen*
3 - Display RBGI 16 colors
4 - Video composite (NTSC) or Chroma/Luma

Note: the RCA jack for composite "Video" is also used for "Luma" when using the Chroma jack

* For green screen, if in analog (position 1), switch to position 2 for green screen of analog signal. If in RGBI (position 3), switch to position 2 for green screen of digital signal.

Here are some specs of note:

Video Bandwidth: 4.5 MHz (NTSC), 12 MHz RGBI
Resolution: 580x240
Horizontal Frequency: 15.7 KHz
Vertical Frequency: 50/60 Hz

 

[ajacocks]

Welcome to the forum @rager69 !

- Alex