PS1 SCPH-1052 PCB scheme

[sl1pkn07]

Hi

i have an PS1 SCPH-1050 JP21 scart cable. and i want to transform to European SCPH-1052 cable. the main difference is the PCB supplied in the Scart connector, but i can't find any good picture or schemes for try to clone it

anyone can help me?

greetings

[Link83]

Not sure how helpful these will be, but I saved these photos I found in forums some years ago:-

SCPH-1052 Official PS1 SCART Cable


SCPH-10142 Official PS2 SCART Cable


I believe Sony used basically the same design for both the PS1 and PS2 official SCART cables, and that the main difference was the cable/plug color (PS1 is grey, PS2 is black)

[BazookaBen]

Dang, these are quite a bit more complex than anything you’d buy today. What do those 3 chips do?

[Link83]

Dang, these are quite a bit more complex than anything you’d buy today. What do those 3 chips do?

Their main purpose is just to step-up the voltage from 5V to 12V for the SCART 'switch signal' to denote a 4:3 aspect ratio:-
https://en.wikipedia.org/wiki/SCART#Bla ... _switching

Most modern SCART cables just use the 5V directly and don't bother with this as SCART will still 'switch' with 5V. However if you were using a late model 2000's era European CRT TV this would denote a 16:9 signal and potentially either stretch the image to fill the screen (on a 16:9 TV) or squish the image and introduce black bars at the top and bottom of the screen (On a 4:3 TV) automatically, and on some TV's this feature could not be disabled.

Its not really much of an issue nowadays as many SCART switchers dont even rely on the SCART switching and blanking signals to detect a signal (e.g. the Gscartsw uses the video sync to detect a signal and by default outputs SCART switching and blanking signals that denote 4:3, regardless of what the input is) and even then your usually connecting to a scaler which often ignores these signals entirely and allows you to adjust the image aspect ratio however you want. It only really poses an issue for people still using late model European CRT TV's.

As an aside, the official Mega Drive 2 SCART cable also used a step-up voltage circuit in the SCART plug, but it was badly designed and actually ended up introducing noise into the video signal (Article in French):-
http://www.segakore.fr/index.php/2004/0 ... defectueux

Some other PAL consoles instead chose to remove the CSYNC signal from the AV output and replace it with 9-12V for SCART switching, for example the PAL Sega Saturn, PAL SNES and PAL GameCube consoles (Which is what makes it potentially risky to use direct CSYNC cables in a setup with any PAL consoles)

[sl1pkn07]

Hi

thanks for the photos. is strange because the OEM JP21 cable (scph-1050) have caps in the RGB signals, but in the OEM European (scph-1052) not...





and in all sites claims the OEM PS1 scart cables have external caps because the console lack that capacitor internally, but in the PS2 consoles have the caps internally...

i'm not remember were i see that, bur exist 2 version of the OEM PS1 scart cables? the later cable is incompatible with DVD players(?)

greetings

[Xan]

As the previous poster mentioned it's usually said that the PS2 doesn't need the 220µF caps in the RGB cable because they are already in the console, and the PS1 does need them, but looking at PS1 boards there are still loads of 220µF caps near the multi-AV on most revisions - as many as 8 on the early PU-7 board, which is more than what the PS2 has. Anybody knows for sure that these aren't on the RGB lines? Reason I'm asking is that the output on my SCPH-1000 seems to be ever so slightly dimmer compared to other revisions, which would be consistent with caps on the board being in series with those in the cable. I have not seen anybody discuss revision differences in that way for the PS1 so far.

Of course the notion that the JP21 cable has the caps and the European one doesn't would contradict that, and the picture posted in this thread is inconclusive. Can anybody say for sure that the European SCPH-1052 cable doesn't have the caps? And by the way, since I think it's not mentioned in this thread, I've read elsewhere that these cables actually strip CSync from the composite line, which makes sense because of the issues with crosshatching when using composite as sync, but I guess they really went out of their way here instead of just using luma as sync.

[Xan]

I have the SCPH-1052 now and am trying to figure out what the deal with this cable is. Judging by what I've read a lot of people don't seem to realize yet that this cable most likely doesn't have the capacitors. Just in case they put tantalums in the AV connector plug or put them somewhere else inline, I put an ESR tester to the RGB lines and it's just showing a 2.6 ohms resistance, no capacitance. Looks like there really are no caps hidden in this cable.

My only guess is they removed the caps to make room for this voltage converter IC and its passives, used just for that stupid SCART AR selection voltage, which should really have been left NC in the first place. A very strange decision to say the least. I've also come across pictures of this cable where these spots aren't even populated.

So if the RGB lines aren't AC coupled I understand using this cable could put equipment at risk of damage by voltage spikes/transient currents, or overload the RGB encoder. The CXA1645 datasheet explicitly says it can't drive a 150 ohm load with DC coupling, only with AC coupling, and says to use 220µF caps on the outputs. I believe early PS1s (PU-7/PU-8) used that encoder. So is this being run out of spec with this cable?