I'm putting up this post so everyone can have a good laugh, but maybe also learn from my mistakes.
I learned the technique of Jamma to Scart right here on DLF, and it has inexpensively brought two machines back to life for me by having TV's inside, this knowledge I am very grateful for, the many old posts of Level 42 especially helped a lot on this and other forums.
I have posted before that I bought cables from ebay, and I've had a lot of success with them, I know how easy they are to make for you guys, but I took the quick easy route before and continued to do so.
I recently bought another from the same guy, and proceeded to wire up as normal.
However I was getting crazy interference and scrolling on the TV I wanted to use. I tried other TV's and they worked, but they would not be the right size, picture not perfect, but a picture, I blamed the PCB and started pulling on off the chips etc, checking edge connectors, voltages etc etc..
It was not making sense, I tried another TV and the SCART lead would not switch the TV to AUX, how odd, that TV always does that when scart is connected to the DVD. hmm
I've fussed around with this lead for weeks, blamed TV's, spent many hours researching every SCART and RGB wiring diagram since the cavemen times.
So, here's where it all went wrong. I get these leads and all the RGB Sync and GND are nicely labelled, the power source is nicely put onto an ATX PC type connector so you can run it from a PC power supply....but I don't want to do that, why have an extra power supply in the machine right, just hook up the yellow to 12V, red to 5v, black to GND.
Hell it's worked before...yellow is always 12v, red is always 5V, and black is GND...ever since ....always.
so today I lost faith in my lead supplier, decided to check the perfect lead that I has always received since everything else seemed to work, one last investigation, I was not expecting this result.
SHIT.
12V and 5V were mixed up. I checked this by looking at the continuity from the scart diagram for the 5v and 12V, what pin they should be on the scart.
I pulled one exact same lead out of another machine, and true enough, the ones I had previously has 12v yellow, 5v red.....but not this new one these were reversed.
So the story ends happily, I can switch these wires and I will get a great picture with the TV I wanted to place in the machine.
But the message is, never never assume that something you receive is wired the same way as you expect.
Because I clipped the connector off, it may have been wired up in theory correctly, bit since I clip it off it took me down a month of wasted weekends.
Don't waste your weekends guys, if you buy these leads, check the pins.
maybe...moral of the story is, don't be lazy, make your own leads, this is what I will do from now on.
