Connecting different Amigas to Sony PVM monitor via RGB

[ramonsmits]

I've read the following posts about connecting the Amiga to a RGB+SYNC monitor:

- http://eab.abime.net/showthread.php?t=28116
- http://eab.abime.net/showthread.php?t=68447
- http://eab.abime.net/showthread.php?t=76742


I currently have a Amiga RGB to SCART cable, without any resistors which works fine on my LCD TV's and and Philips CM8533 monitor but I would want to connect my 500, 600 and 1200 to a Sony pvm-14m4e

I made a SCART to 4x BNC breakout cable to create the following chain:

Amiga RGB -> SCART -> 4x BNC


However, it doesnt work :-( but it is not clear to me what to do next.


Some questions:

- Must I connect the BNC grounds to get a signal?
- Must I add a 330 Ohm resistor on CSYNC signal between the Amiga RGB pin 10 and the Sony PVM EXT SYNC input?
- Should the Sony pvm-14m4e work with CSYNC on the SYNC EXT input?
- Should I use the Amiga composite output instead of Amiga RGB pin 10 (CSYNC)?
- If using composite output on the Amiga, would that work with all models?


Additional info about my setup


Sony pvm-14m4e:

The service manual states the following about the inputs:

- BNC's are 75 Ohm
- R, G, B channels: 0.7 Vp-p, ±6 dB (Sync on green: 0.3 Vp-p, negative )
- EXT SYNC: 4 Vp-p, ±6 dB, sync negative

I can't find any info about if the EXT SYNC port needs CSYNC, HSYNC and/or VSYNC.


Amiga RGB to SCART:


Ian Stedman has a nice schematic for a Amiga RGB to SCART cable:

http://www.ianstedman.co.uk/Amiga/am...iga_scart.html

He uses some resistors, most notable a 330 Ohm resistor on CSYNC.

[thgill]

Originally Posted by ramonsmits

I've read the following posts about connecting the Amiga to a RGB+SYNC monitor:

- http://eab.abime.net/showthread.php?t=28116
- http://eab.abime.net/showthread.php?t=68447
- http://eab.abime.net/showthread.php?t=76742


I currently have a Amiga RGB to SCART cable, without any resistors which works fine on my LCD TV's and and Philips CM8533 monitor but I would want to connect my 500, 600 and 1200 to a Sony pvm-14m4e

I made a SCART to 4x BNC breakout cable to create the following chain:

Amiga RGB -> SCART -> 4x BNC


However, it doesnt work :-( but it is not clear to me what to do next.


Some questions:

- Must I connect the BNC grounds to get a signal?
- Must I add a 330 Ohm resistor on CSYNC signal between the Amiga RGB pin 10 and the Sony PVM EXT SYNC input?
- Should the Sony pvm-14m4e work with CSYNC on the SYNC EXT input?
- Should I use the Amiga composite output instead of Amiga RGB pin 10 (CSYNC)?
- If using composite output on the Amiga, would that work with all models?

Yes, the BNC grounds need to be connected to ground.

Resistor on the Csync to EXT Sync isn't necessary. Won't hurt, but isn't necessary. But it's worth trying if all else fails.

Most PVMs will work with either Csync or Composite video as sync ran into the EXT Sync.

Additional info about my setup


Sony pvm-14m4e:

The service manual states the following about the inputs:

- BNC's are 75 Ohm
- R, G, B channels: 0.7 Vp-p, ±6 dB (Sync on green: 0.3 Vp-p, negative )
- EXT SYNC: 4 Vp-p, ±6 dB, sync negative

I can't find any info about if the EXT SYNC port needs CSYNC, HSYNC and/or VSYNC.

The EXT Sync requires a muxed sync signal, so use either Csync or composite video.

[ramonsmits]

Originally Posted by thgill

Yes, the BNC grounds need to be connected to ground.

Resistor on the Csync to EXT Sync isn't necessary. Won't hurt, but isn't necessary. But it's worth trying if all else fails.

Most PVMs will work with either Csync or Composite video as sync ran into the EXT Sync.

The EXT Sync requires a muxed sync signal, so use either Csync or composite video.

Ok, time to grab the soldering iron and connect the grounds. Based on this I do not need to connect anything to the Amiga monochrome/composite video port.


The composite video, that is just CSYNC + RGB multiplexed right?

[thgill]

Originally Posted by ramonsmits

The composite video, that is just CSYNC + RGB multiplexed right?

More or less.

The PVM just strips out all the non sync info when you run it into the EXT Sync.


Also, if you have a device that outputs both Svideo and RGB (like the Super Nintendo or Sega Saturn and etc), instead of using either composite sync or composite video as sync, you can also use the Luma connection pin going to the Svideo as sync since Luma carries the Sync signal (along with black and white video info).


Only really old PVMs (like from the 80's) require a strict composite sync signal on the EXT Sync.

[ramonsmits]

I did two things:

- Soldered the grounds on the SCART to 4X BNC breakout cable.
- Added resistors on the Amiga RGB pins from Ian Stedman his diagram.


It is now working. I think soldering the grounds resolved it. SCART cable also still working on my TV so I'm happy with that too knowing the circuitry isn't that stressed now due to high voltages.

So that means the PVM 20M4E and 14M4E do not require a sync stripper when connecting it to an Amiga. Tested this with a 500 and 600. So an Amiga that has monochrome and one that has composite output.

[thgill]

Glad to hear that it now works on your PVM.

[nobody]

I am not an expert but i think that if you don't give 1V or something with a resistor to a scart pin (16?) then the signal is not RGB

[idrougge]

That is only relevant for TVs with SCART.