Here is another option to connect the RGBI output to a monitor/TV using SCART. I've never seen a SCART TV where I've lived, but I hear they were very popular in Europe. I don't know if this should be considered modern, but it is another option.
To get 16 colors he used the pull-both circuit I published earlier. This means he gets dark yellow instead of true brown. He also reports the display is too dark without adjusting the contrast on his TV. Probably needs smaller resistors in the pull-both circuit.
Last year I built almost the same cable (thanks hydrophilic for your pull-both circuit!), but I added a switch to have 40 column composite signal on the SCART as well. I didn't put 1K resistors on the +5V line, in my case I seem to not need them, but that it could be just me. What I found to be really usefull was to swap the 1K and 1.2K resistors in the pull-both circuit with 1K variable resistors as with the "default" ones colors was too feeble. That way I could adjust the intensity of each color.
Nice to hear to about your SCART experience. I used variable resistor for testing too (s-video / vga), and the fixed resistors shown were based on that. Based on your report, and Tero's, it seems SCART in general needs higher voltage (smaller reststor). Although I have no way to determine optimal value myself.
Ha ha, if you look at my VGA page, you can see adapter I made for Miro has variable resistor on everything This is because we could not find reliable info about his VGA adapter.
I actually put two resistors on the RGB enable line based on Tero's description of SCART (shown in schematic) to be safe. I thought you could probably get away with just one... glad to hear that you can get away with zero! I guess I should update my webpage to tell people.
So you made yours switchable with 40-column? That's cool! I assume you switch in the VIC signal on the composite/sync line in 40-column mode... but how did you drive composite/sync when it was in 80-column mode?
I must add that, while having a single cable for both 80 an 40 column could be really convenient, quality of 40 column signal (composite) is really disappointing. Of course I'm blaming my lack of skill with soldering irons (I found particularly painful soldering wires to the damn DIN-8 connector's pins !) above anything else, but nonetheless...
Next time I'm planning a dual input - dual output harness, using a SCART connector for 80-column and an S-Video one for 40-column. It will require fiddling with the TV remote or controls to switch from 80 to 40 columns, but video quality should drastically improve.
Yeah, S-Video is much sharper than composite. But with composite, I don't see any vertical lines that people complain about with 40-column on the C128, so I actually prefer it... reminds me of the old days playing on a C64 at my friend's house using a TV, but he was using the horrible RF signal (thankfully composite is much better than RF).
I don't mind updating the webpage, so thanks again for the feedback.
Edit Oh, yeah, I hate soldering pins for cables too! I prefer to buy a cable and cut it in half (or cut off one end) whenever I can get one... not sure how easy it would be to find a DIN-8 cable, however.
Last Edit: Jul 30, 2014 6:05:12 GMT by hydrophilic: Thought of something else...
On a side-note, to anyone who would like to assemble this cable, beware that the DIN-8 male connector you should use is the 262-degrees type, not the 270-degrees one. I did this mistake myself, and now it's hard to push into the C=128 and probably doesn't make good contact.
Ok, so I designed and am building my own C128 CGA to RGBS adapter. It's dual input taking both the CGA and VIC outputs from the C128. It's output has RGBS+SVid+audio and it powers itself from the 5v on the video connector.