Scart to Component NO PSU Mod

[Androigynous]

Hi there! Long time lurker, first time poster.
I was hooking up my sync strike (set on scart to power) and was intrigued by the fact that it could power the pcb via power going through the cable. I use a scart to component converter and wondered if I could mod it to not need an external psu. I have two of these converters, one I just fuck around with, and one I actually use.
So I grabbed the fuck around converter and attached pin 8 (which from what I know carries 5v) from the scart side to the left pin on the power supply. I then took the audio ground (pin 4) and attached to the ground from the power supply. I plugged it in and the LED lit right up, although somewhat dim. I turned on the TV and it worked, no psu.


I was really excited that this worked so I opened up the converter I primarily use and applied the mod (This unit was modded to have the audio broken out). I got an even dimmer light on the LED than the previous one. It worked for a couple minutes, yet the colors were all changed like I was playing with the RGB pots (I have not). It then stopped working altogether. I undid the mod, then plugged it back in with the PSU and the colors were back to normal. I have no idea why it works for one but not the other. Does it have something to do with the previous mods? Any help, advice, criticism is appreciated.

The primary use converter.

The previous mod.

solder side previous mod.

[matrigs]

nice little mod.

probably the sound output drained too much juice so it would stop working.

what about the quality of the converter ? any problems with it ? thoughts ?

[Androigynous]

Yea, I'm thinking about trying out different ground points to see if that changes anything.

As for thoughts on the unit: It looks really nice on a CRT. We don't have Scart on our TVs here so I don't have anything to compare it to in terms of actual RGB. But its not the prettiest on an LCD. It gets stretched and washed out (thats why we have scalers). There are pots on the inside where you can adjust the RG and B. This one is only $50, there are more expensive ones; I talked to someone who has one that's double the price and he prefers this cheaper one. I could post quality pics if you'd like.

The only issues I have with it are: no audio out (which you can easily build in yourself). And I'd prefer to not use that external power supply (but I'm working on it).

[Androigynous]

Figured it out. I applied both the audio and no psu mod to the test (or fuck around) board. Everything works! There might be variance in the boards models...I don't know. So now my "good" converter will be my fuck around converter. Hopefully someone on here uses one of these and can benefit from this. I notice no difference at all in image or sound compared to using the ac adapter. Here are some pictures:

Completely powered by the Scart cable alone.

[fagin]

This is of course assuming you have a valid PIN 8 connection and decent voltage. In some external applications you really needed a regulated supply. It's one of the main reasons for ext. pwr being the only full proof option. If it works for your console(s) then that's all that counts in this case though.

[Androigynous]

As of right now, I only use it for my megadrive/genesis. I tried it on my saturn and no power went through, so I'm assuming different scart leads/systems treat pin 8 differently. The saturn lead also doesn't work on my sync strike when switched to 'scart' power so I assumed it wouldn't work. When I want to use that I have to connect external power to the sync strike. Not sure if it's just the cable or if the saturn outputs 5v on that pin.