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Author Topic: How to use SCART for our hobby  (Read 242938 times)

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Em

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Re: How to use SCART for our hobby
« Reply #160 on: November 23, 2009, 06:32:00 pm »
Hi Zeb,

thanks for the info. I think I need to get a TV that's slightly less old then! I'm not sure if there's a v-hold knob inside the set and I don't really want to open it up. I did try getting into the service menus on it a few times to see if there were some settings I could adjust, but entering the sequence of buttons on the remote causes the whole TV to freeze. It wont even turn on. Have to disconnect the power for a minute or so to let it recover!

Thanks again.

Em.

ceekay011

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Re: How to use SCART for our hobby
« Reply #161 on: December 02, 2009, 05:17:53 pm »
hello everyone

trying to connect a vga to scart on my hantarex CT EQ/3 28"  : http://www.hantarex.be/BtoB/pdf/cteq3.pdf
i have made a cable without the 12v : : http://www.alvarezeninternet.com/mamescart/scartuk.jpg
know i am having broblems with the colors....on the back of monitor there is a switch from video to rgb to off , and when i switch between rgb and of i get a spit second good collors  ??? alsow wen i tik the ground cabels from vga to some of the pins on the scart the same thing happens .
sorry if my english and discripsion isnt that good . 

s-video


vga to scart



mamewah front made with  photoshop  ;D

Zebidee

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Re: How to use SCART for our hobby
« Reply #162 on: December 05, 2009, 03:20:14 am »
@ceekay

I thiink the reason why your TV doesn't work so well is because you don't have any RGB switching signal @ SCART pin 18 16.

BTW, to be consistent w/ earlier posts, in this thread I am referring to this SCART pinout chart:

http://pinouts.ru/Home/Scart_pinout.shtml

In earlier parts of this thread, you can find instructions on various ways to get the ~ 1-3 volts you need to this pin.

The easiest way may be: cut a small piece of wire ~ 3-4cm long (about 1.5 inches) and make a 'bridge' from pin 20 (sync) to pin 18 16. But this doesn't work for all TVs.

If your cable has the right wires, and you have an ATI video card (inc ArcadeVGA) or other card, you can tap into the 5v on VGA pin 9. Put a 100ohm resistor on the end of the 5v wire (VGA pin 9 ) and attach it to pin 18 16.

Best way is to hack a standard molex power supply cable (the big one with 4 wires: yellow, black, black, red). You need the red wire (5v) and one black wire (it doesn't matter which one). Extend the cable (ie solder some wires on) and feed the ends into your SCART header. Put 100 ohm resistor on the 5v red wire (now it is 2v), and attach to SCART pin 18 16. Attach the black ground wire to pin 16 18.

Bet you this works!
« Last Edit: December 12, 2009, 07:16:49 am by Zebidee »
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ceekay011

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Re: How to use SCART for our hobby
« Reply #163 on: December 06, 2009, 05:54:09 pm »
wil Try tis out and report back on the forum if it works Zebidee  :)
i have vga 13 to scart 20 and vga 14 to scart 18 and a bridge from 20 to 18 , is this good ?

Zebidee

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Re: How to use SCART for our hobby
« Reply #164 on: December 07, 2009, 07:23:04 am »
wil Try tis out and report back on the forum if it works Zebidee  :)
i have vga 13 to scart 20 and vga 14 to scart 18 and a bridge from 20 to 18 , is this good ?

No. you need to twist VGA 13+14 together and attach to SCART 20. The bridge from SCART 20 to 18 is good.
The bridge should be from SCART 20 -> 16

If that 'bridge' doesn't work well, you should try one of the 5v + 100ohm resistor methods.
« Last Edit: December 12, 2009, 07:11:36 am by Zebidee »
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maiki

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Re: How to use SCART for our hobby
« Reply #165 on: December 07, 2009, 09:12:59 am »
There is NO quality difference in picture between a "real" arcade monitor or a TV that is used with RGB.

There is a very good reason why you should not go for TV and get yourself arcade monitor instead. I was testing 2 EU CRT TVs back in 2004 with Advance MAME and ADVV utility. Those TVs were not able to display full 240 active scanlines at 60 Hz. Period. Reason being probably the electronics or whatever that drives the picture is not designed so well as arcade gaming monitors. For the same reasons none of the home consoles display full active 240 scanlines at 60 Hz. You always get lower number. Atari VCS as low as 192 (depends on carts really)... most consoles end up on 224 active scanlines at 60 Hz. Period. That being said, you will never get the same quality with consumer CRT TV as you would with real gaming  arcade CRT monitor.

ceekay011

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Re: How to use SCART for our hobby
« Reply #166 on: December 08, 2009, 12:46:58 pm »
Best way is to hack a standard molex power supply cable (the big one with 4 wires: yellow, black, black, red). You need the red wire (5v) and one black wire (it doesn't matter which one). Extend the cable (ie solder some wires on) and feed the ends into your SCART header. Put 100 ohm resistor on the 5v red wire (now it is 2v), and attach to SCART pin 18. Attach the black ground wire to pin 16.

Bet you this works!

[/quote]

it did not work

cant get any image

only have image when i connect vga 13 to scart 20 and vga 14 to scart 18 and a bridge from 20 to 18


ceekay011

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Re: How to use SCART for our hobby
« Reply #167 on: December 09, 2009, 04:00:41 pm »
Got it to work :)




The 12V kabel is optional

thanks to all for the advice  :applaud:

Zebidee

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Re: How to use SCART for our hobby
« Reply #168 on: December 09, 2009, 08:05:48 pm »
@ceekay011  - that cable seems a bit crazy, but if it works for you then it works!

@maiki

TVs are variable, but generally better quality than arcade monitors. Most arcade monitors have pretty cheap/poor quality components inc. tubes, but are more flexible (e.g. viewable screen size, adjusting overscan) than TVs.

The right TV is fantastic, poops all over most arcade monitors. Looks like you got some dud TVs. I always go for good quality Euro brands like Thomson, Loewe & Grundig etc.
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ceekay011

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Re: How to use SCART for our hobby
« Reply #169 on: December 12, 2009, 05:59:36 am »
@Zebidee

what do you find crazy on the cable ?

 

Zebidee

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Re: How to use SCART for our hobby
« Reply #170 on: December 12, 2009, 07:08:30 am »
@Zebidee
what do you find crazy on the cable ?

Hmmm. I made a mistake in some of my recent posts: SCART 16 is RGB switching, not SCART 18. Very, very sorry about that! It may have probably caused you some frustrations. I think I'll go and edit my earlier posts to fix the errors in case someone else follows them.

Anyway, moving on, this is what I find crazy:

1) You direct VGA14 (Vsync) -> SCART 16, which has nothing to do with sync! SCART 16 is for RGB switching.

2) shorting/bridging SCART 16 -> 20 is good, but it now means that you are effectively twisting VGA 13+14 together anyway (which was recommended earlier)

3) Why do you need the 1k resistors on sync lines? This might cause you some sync problems. But if all is OK, then what can i say!

I imagine that you might have some interference on the sync. You might find that the sync improves if you just twist VGA13+14 together and hook them up to SCART 20, either with or without the 1k resistors.

« Last Edit: December 12, 2009, 07:24:40 am by Zebidee »
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Level42

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Re: How to use SCART for our hobby
« Reply #171 on: December 12, 2009, 07:45:46 pm »
@Zebidee
what do you find crazy on the cable ?

Hmmm. I made a mistake in some of my recent posts: SCART 16 is RGB switching, not SCART 18. Very, very sorry about that! It may have probably caused you some frustrations. I think I'll go and edit my earlier posts to fix the errors in case someone else follows them.

As indicated in the very first posting in this thread  :D :D :D :D

hey, we're only human :D

Zebidee

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Re: How to use SCART for our hobby
« Reply #172 on: December 12, 2009, 08:37:33 pm »
@Zebidee
what do you find crazy on the cable ?

Hmmm. I made a mistake in some of my recent posts: SCART 16 is RGB switching, not SCART 18. Very, very sorry about that! It may have probably caused you some frustrations. I think I'll go and edit my earlier posts to fix the errors in case someone else follows them.

As indicated in the very first posting in this thread  :D :D :D :D

hey, we're only human :D

Corrections have been made to earlier posts ....

@Level42 - It occurs to me that people actually read this thread through from the beginning (5 pages now!), then they would be able to answer most questions themselves.

My work has been flat out lately. Sometimes responses are written off the top of my head, in a few rare moments during infrequent breaks, often in a rush before 'the boss' comes out and wonders what I'm up to. Mistakes are regrettable but bound to happen  :dunno

Wanna know what I've been working on so frantically? Check out the #bbfuture (Broadband Future) hashtag on Twitter. Became the most popular hashtag in Australia, and most popular topic on Twitter in Australia except for Christmas, over past few days.
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Level42

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Re: How to use SCART for our hobby
« Reply #173 on: December 13, 2009, 11:45:56 am »
Man, you're doing a fabulous job on maintaining this thread. All I did was gather some bits of info and open the thread with it.

What you say is probably right, every answer should be in here by now.... :D

And congrats on your work, although I have no clue what you're talking about. I know Twitter, took a look at it and de-installed it after a week. I probably miss the point, or am finally getting "too old for this stuff". :D

Zebidee

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Re: How to use SCART for our hobby
« Reply #174 on: December 13, 2009, 02:37:07 pm »
Man, you're doing a fabulous job on maintaining this thread. All I did was gather some bits of info and open the thread with it.

What you say is probably right, every answer should be in here by now.... :D

And congrats on your work, although I have no clue what you're talking about. I know Twitter, took a look at it and de-installed it after a week. I probably miss the point, or am finally getting "too old for this stuff". :D

Thx Level42!

BTW, Twitter is not 'installed' - you make an account and can access it through a web interface. It is a popular online social comms tool but is not for everyone. In particular it is meaningless unless you link to other people ('tweeple') and follow them/are followed.

However, the info you can get out of Twitter feeds can be invaluable for tapping into the 'pulse', as it was for #bbfuture.

I don't want to sidetrak the thread, but if you want an old-skool way of understanding what I was talking about, click here for broadband future.
« Last Edit: December 13, 2009, 02:39:55 pm by Zebidee »
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ceekay011

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Re: How to use SCART for our hobby
« Reply #175 on: December 14, 2009, 12:00:58 pm »
@Zebidee
what do you find crazy on the cable ?

Hmmm. I made a mistake in some of my recent posts: SCART 16 is RGB switching, not SCART 18. Very, very sorry about that! It may have probably caused you some frustrations. I think I'll go and edit my earlier posts to fix the errors in case someone else follows them.


I was a bit wonderd about the "SCART 16 is RGB switching, not SCART 18"   ??? but i did read the other post and saw that you made a mistake  ;)

1) i will see again if the sync works like you sade in the post

3) 1K i saw it other forum http://translate.google.com/translate?hl=en&sl=it&tl=en&u=http%3A%2F%2Fdigilander.libero.it%2Fventuri1975%2F wood be safer for the tv , doint know if it true

what of interference on the sync do you mean ?


Zebidee

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Re: How to use SCART for our hobby
« Reply #176 on: December 18, 2009, 02:31:25 pm »
1) i will see again if the sync works like you sade in the post

3) 1K i saw it other forum http://translate.google.com/translate?hl=en&sl=it&tl=en&u=http%3A%2F%2Fdigilander.libero.it%2Fventuri1975%2F wood be safer for the tv , doint know if it true

what of interference on the sync do you mean ?

Sync input standards for most SCART TVs is actually 1-5v! It is only the RGB inputs that need to be 0-1v.

Many video cards output sync at close to 4.5 to 5v - it varies a little.

A JPAC fro Ultimarc will actually pull this down slightly, and output sync at around 3.3-3.5v

Pull the sync voltage lower than 3v and you may have problems with your TV accepting the sync signal.

I've tried lowering the JPAC's 3.5v further with a 75ohm resistor to around 2.0 -2.5v, and had problems locking into the sync - the top part of the screen was out diagonally. Tried another TV and got the same result. Tried another TV and it was OK, but harder to sync in. Removing the resistor solved the problems

Key lessons from this:

1) don't put a resistor on the sync in line, because SCART accepts 1-5v already  OR
2a) only use a 47ohm or max 75ohm resistor on (which should lower the VGA sync voltage from 5v -> about 3v) AND
2b) use a multimeter & keep part of the sync wire exposed around the resistor so that you can test the voltages while in use.

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Re: How to use SCART for our hobby
« Reply #177 on: January 11, 2010, 10:48:14 am »
Finally, to access the Service Mode, you must first select program 91 and set "Sharpness" to minimum, then very quickly press "Red", "Green" and "Menu" in turn, then "OK".
Bloody hell! Does it say "Simon says" in the beginning?  ;D

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Re: How to use SCART for our hobby
« Reply #178 on: January 17, 2010, 10:43:19 pm »
Hi all. I have a strange problem with my vga-scart cable/TV, and I'm in need of help.

I have 2 TVs, and 2 graphics cards on the same PC.

In the first TV (we'll call this the "BAD TV"), both my arcade PC and my Nintendo Wii are connected to the same scart RGB port, using an adapter. Obviously I have only one device on at any time, the PC or the Wii.

In the second TV (we'll call this the "GOOD TV") my VGA-Scart Cable works flawlessy, with both the first and second graphics card.

In the BAD TV, the colors have a defect I cannot describe. It's evident when looking at the "color bar" in the card properties, under color depth: the color aren't distinct, red green and blue blend: red blends with purple, cyan with yellow, green is faint. Yellow and purple show fine.
But, if I look at the icons on the desktop there's no color bleeding/shifting: red, green and blue look fine on their own.

Now the strange thing: If I connect both the vga-scart and the Wii Scart cable (Wii powered off, not connected to AC adapter), the colors are correct. If I connect only the vga-scart, the colors have the problem described above.
The same cable when connected to the second TV (Good TV) works fine.

So, I investigated what was different in the Wii Scart cable even with the Wii not connected to power, and it looks like Red and Green get between +1,5v and 2,4v, while Blue gets between -1,5v and -2,4v (yes). Those values were misured with my multimeter, using the voltmeter and testing scart pin 17 as ground and the red,green blue scart pins. The other pins don't affect the signal. Only pin 17 acts as ground, the other grounds are not present in the Wii RGB scart cable.

In short, looks like my BAD TV would prefer having a "stronger" colour signal, where the Good TV doesn't care.

Any idea on how to solve this, other than keeping the wii-scart cable connected at all times?

I would change the TV with a newer one, but new CRTs are hard to find and I don't have money. :(

There must be a way to make it work...

Any and all help appreciated.

Zebidee

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Re: How to use SCART for our hobby
« Reply #179 on: January 18, 2010, 07:04:58 am »
We need more information ....

Q1 Exactly how is your VGA-SCART cable wired?
Q2 What brand TVs are we talking about?
Q3 What video card are you using?

I don't think that voltage levels are the problem.

Does the colour work when just the wii cable is plugged in, and not the Wii itself? I suspect the presence of the cable is detected by the TV and it responds by auto-selecting composite for the Wii cable and RGB for the VGA-SCART cable. I suspect that your VGA-SCART cable is not doing this properly by itself.

We need to know how your VGA-SCART cable is wired. So far my guess is that it has something to do with your cable's grounds or perhaps RGB/mode signals. Different TVs have different levels of fussiness about these things.
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Re: How to use SCART for our hobby
« Reply #180 on: January 18, 2010, 10:03:36 am »
Sorry for not providing more informations earlier. I have conducted various tests, and I'm still going mad.

I am using PCI (not PCIe) ATI Radeon 9250 with 128MB RAM.

My VGA-SCART cable is wired in the simplest manner:
VGA 13&14 twisted together to get composite, connected to scart pin 20.
A bridge between scart pin 20 & pin 16 to give it the rgb signal. If pin 16 is not connected the TV can't display the image even when setting it to EURO AV.
The R G and B colors connected to the proper pins on SCART.
All grounds (R G B, vga pin 10 and VGA chassis ground) twisted together and connected to scart pin 5 (blue ground).

I have tried various grounding combinations (the ground colors where separated before), nothing changes. The scart pin 16 gets 2,4v, so it's within standards 4,5v, turns out the measurements done on the scart end of the vga cable were different than those who arrived at the TV.

The color doesn't work with only the Scart Wii Cable. It needs to be shorted to the Wii.
NOTE: in the wii only scart pins 17, 15, 11  and 7 need to be connected for this to work. I disconnected all the other pins, they have no effect.

The same thing applies when using a gamecube and its rgb cable instead of the wii.
The TV is generic, a no-brand. I don't know the manufacturer.

NB: The TV is not so old as I make it sound. I purchased it in 2006. It has menu options even for color modes (Pal, secam, two different ntsc, auto), but they don't solve the problem.

UPDATE:
Sacre Bleu!
If I put a 1N4148 diode between Scart Pin20 and scart Pin17 (that is now empty), the colors show fine!

UPDATE 2:
So, I noticed that, with the Wii connected, the voltage on pins 15 11 and 7 was around -4,5v (using pin 17 as ground).
Since I have +4,5v on pin 20, I used that.
The diode is added like this: Pin20 ->|- Pin17.

Now I can't keep the Wii scart connected, or the image gets darker (dim), and with a little distortion between high contrast elements (brights objects on black background).

Any idea on what's going on is appreciated...
(The Wii has been used a lot of times. The PC has seen a lot less use as of later.)
« Last Edit: January 18, 2010, 11:33:53 am by Eversynth »

Zebidee

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Re: How to use SCART for our hobby
« Reply #181 on: January 18, 2010, 05:31:29 pm »
It occurs to me that your VGA-SCART cable has no ground at pin 17! This is probably the most important grounding pin.

But when the Wii cable is plugged in, the Wii provides a ground for pin 17 (even when turned off). I suspect that the pin 17s on both of your TV's SCART inputs are common.

You should try hooking ground up to pin 17 on your VGA-SCART cable. Have you tested for continuity between your gnd at SCART pin 5 and pin 17? You might find that they are not common & therefore that there is no ground for your sync signal. Bridge these pins with a short wire.


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Re: How to use SCART for our hobby
« Reply #182 on: January 18, 2010, 07:44:57 pm »
Quote
This is probably the most important grounding pin.
Good to know, so that's why in Wii & gamecube cable that's the only ground wired.

But I have to tell that before wiring up the VGA-SCART the way I have now, it was different:
I had:
Code: [Select]
VGA 13 & 14 - Scart 20
VGA 10 - Scart 17
VGA R G B to Proper Scart R G B
VGA R G B grounds to Proper Scart R G B grounds
Scart 16 bridge with Scart 20
VGA shield ground to Scart shield ground

In fact, the second VGA-Scart cable is still wired like this. And it works fine only in the second, "Good TV".

The VGA pin 10 ground in Scart 17 ground doesn't affect at all the outcome.
Quote
Bridge these pins with a short wire.
In the new cable I already tried shorting Scart Pin 5 (all grounds) with Scart Pin 17, to no avail.

The only solution seems to be using the 5v coming from the vga 13&14 and put it on scart 17 with the diode, to get the needed(?) negative voltage on the scart R G B pins. :/

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Re: How to use SCART for our hobby
« Reply #183 on: January 19, 2010, 02:10:58 am »
You've got me - I can't see why you have the problem, nor truly understand why the diode helps. Which way around was it?

You could try the 5v -> 100ohm resistor -> 2v -> SCART pin 16 (and gnd to pin 18) trick. This might give you a more consistent RGB switching signal.

I'll normally use this kind of cable, also with 12v at pin 8, as a 'baseline' cable for SCART TVs. I have one lying around somewhere in casew I need it. I have never yet seen a RGB SCART TV that not accept this input and give a clear picture.
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Re: How to use SCART for our hobby
« Reply #184 on: January 19, 2010, 09:06:34 am »
Quote
nor truly understand why the diode helps. Which way around was it?
The diode ground on pin 17, the other on pin 20.
It helps in giving current to the colors signal, albeit a negative one. The reason why it works only with pin 20 could have something to do with the sync signal coming from it.
I don't know what's going on.
The only logical explanation is that the TV needs some voltage in the RGB pins.
Without my trick the Vga outputs only between +0,01v and +0,02v there.

Maybe something broke in the tv, even if it seems unlikely.

All of this started because I wanted to add the 12v on pin 8 and 2v on pin 16, and then (maybe for the first time with the Wii disconnected) I noticed the colors problem. :)
It wasn't even really noticeable without looking at a color gradients pattern.

I don't know if something in the tv might have broken when I connected the 12v coming from the PC molex to the scart (it was a little higher, between 12v and 12,5v).
For sure it worked, switching automatically to the correct AV channel.
I'll think later about adding those again.

In the meantime I will have to keep the PC and TV on for an unprecised amount of time, to see if something breaks....  :timebomb:  :D
I'll let you know if everything keeps working after testing.
« Last Edit: January 19, 2010, 09:15:24 am by Eversynth »

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Re: How to use SCART for our hobby
« Reply #185 on: January 20, 2010, 02:11:56 am »
If RGB signal levels are the problem, then you could try running the RGB signals through a video amplifier, which you can find on a JPAC. Ultimarc also sell video amps separately. They are reasonably priced, only $21.

http://www.ultimarc.com/vidamp.html

If you try this, I'm very interested to know the result.
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LeedsFan

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Re: How to use SCART for our hobby
« Reply #186 on: April 25, 2010, 11:32:38 am »
I've had a go at making my own RGB-Scart cable this morning, but it hasn't gone too well. I'm using the Ultimarc ArcadeVGA card and a VGA breakout cable also from Ultimarc. This cable had the wires labeled for easy reference. (Red, Green, Blue, HSync, VSync and Ground)

What I did was follow the instructions here and soldered the R G B wires to scart pins 15, 11 and 7 respectively. HSync and VSync I wired together and soldered to scart pin 20. I understand this is fine on ATI based cards as they put out -ve on each sync. I then soldered a short jump wire across from pin 20 to pin 16 to try and get the 2-3V ouput there.

Now the breakout cable I have has five different ground wires to just one pin. So all I did was put all these ground wires to pin 13. I didn't solder each R G B ground (or "return" as some people call it) to individual pins. Does this matter? I have no idea which are the separate R G B grounds anyway as these individual grounds aren't labelled.  The cable just has five wires which are all put together and labeled "ground".

When I tried the cable I actually do get an image. But it's just a grey, shadowy image with no colour what-so-ever.

Zebidee

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Re: How to use SCART for our hobby
« Reply #187 on: April 25, 2010, 12:38:12 pm »
It is extra effort, but it looks like you should try making your cable with 5v input + 100ohm resistor => 2v on pin 16
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Re: How to use SCART for our hobby
« Reply #188 on: April 25, 2010, 03:00:34 pm »
It is extra effort, but it looks like you should try making your cable with 5v input + 100ohm resistor => 2v on pin 16

OK I will try that. Just need to get some resistors tomorrow.

But I thought (with my extremely limited knowledge) that if I am getting an image then the jumper wire is doing it's job. I thought it was like a switch.. it's either on or off. And because I'm getting an image then the jumper wire is doing it's job. Or this not how it works at all?  :dunno  Does more/less voltage at pin 16 change matters?

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Re: How to use SCART for our hobby
« Reply #189 on: April 26, 2010, 11:04:40 am »
I've seen this before - Looks like your TV is not properly into RGB mode.

TV is likely looking for composite video and getting some picture signal (e.g. sync) from pin 20 but not proper RGB. You need to add the signal to pin 16 to get the TV to look for signals on pins 7,11,15 (B,G,R)
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Re: How to use SCART for our hobby
« Reply #190 on: April 26, 2010, 02:14:01 pm »
I've seen this before - Looks like your TV is not properly into RGB mode.

TV is likely looking for composite video and getting some picture signal (e.g. sync) from pin 20 but not proper RGB. You need to add the signal to pin 16 to get the TV to look for signals on pins 7,11,15 (B,G,R)

OK I got some 75 ohm resistors today. But before doing anything I checked my connections with a multimeter. I was already getting 4.3 volts at pin 16 with the jump wire from pin 20. However I decided to solder in the resistor and use a separate 5V supply from the PC molex. It hasn't made any difference.  :banghead:

In fact... when I test the voltage at pin 16 with the resistor in line I still get a reading of 5V. Isn't the resistor supposed to lower this voltage? Can this be affecting the picture? Too high a voltage at pin 16?  :dunno

EDIT:  Seem I misread your first post on page 1 Zebidee. I read that you thought 75 ohm resistor gave better results... but on rereading your post you were talking about special cases where resistors were used on the RGB cables.... NOT the switching wire at pin 16. DOH!!!  :banghead:

That's why I got the 75 ohm resistor and not 100 ohm.  :dizzy:  I will get 100 ohm tomorrow and get that voltage stepped down. Having scoured the net it seems that 3V is the maximum that pin 16 should take for RGB switching. Hope I can't damage anything by what I've done so far.

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Re: How to use SCART for our hobby
« Reply #191 on: April 27, 2010, 05:26:06 am »
In fact... when I test the voltage at pin 16 with the resistor in line I still get a reading of 5V. Isn't the resistor supposed to lower this voltage? Can this be affecting the picture? Too high a voltage at pin 16?  :dunno

You must have done something wrong if the voltage is still 5v past the resistor  :dunno

... oh, make sure that you have the cable attached to the  TV and on when you test it with your multimeter, because otherwise you won't be properly completing the circuit.
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Re: How to use SCART for our hobby
« Reply #192 on: April 27, 2010, 12:02:32 pm »
In fact... when I test the voltage at pin 16 with the resistor in line I still get a reading of 5V. Isn't the resistor supposed to lower this voltage? Can this be affecting the picture? Too high a voltage at pin 16?  :dunno

You must have done something wrong if the voltage is still 5v past the resistor  :dunno

... oh, make sure that you have the cable attached to the  TV and on when you test it with your multimeter, because otherwise you won't be properly completing the circuit.

I'm at a loss here. I put the jumper wire back on over pins 20-16 and then retested the voltage with the plug in and TV switched on. I'm getting a reading of 2.5V at pin 16. The picture is still the same. If I have nothing attached to pin 16 it's still the same. Nothing I do with pin 16 seems to help. Is 2.5V still too high? I have all the ground wires from the Ultimarc breakout cable attached to pin 13. The only other ground is at pin 18 (ground for 12V at pin 8 )

EDIT:  Hold on... I've been a right mong here... I just noticed all my RGB and Ground wires are on the wrong pins. What a ---missioncontrol---.  :banghead:  BRB... recitifying buffoonery....

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Re: How to use SCART for our hobby
« Reply #193 on: April 27, 2010, 12:51:48 pm »
EDIT:  Hold on... I've been a right mong here... I just noticed all my RGB and Ground wires are on the wrong pins. What a ---missioncontrol---.  :banghead:  BRB... recitifying buffoonery....

Ahhh - Good luck with that! Let us know how it goes.
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Re: How to use SCART for our hobby
« Reply #194 on: April 27, 2010, 01:48:41 pm »
EDIT:  Hold on... I've been a right mong here... I just noticed all my RGB and Ground wires are on the wrong pins. What a ---missioncontrol---.  :banghead:  BRB... recitifying buffoonery....

Ahhh - Good luck with that! Let us know how it goes.


Still no luck. Now I just get a black screen on AV channel.

I didn't have the RGB wires on pin 15, 11 and 7 before. They were on 13, 9 and 5 with grounds at 11. I was misreading the pin numbers the wrong "side". Really thought I'd solved the problem when I saw I'd done that.  :dunno

Zebidee

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Re: How to use SCART for our hobby
« Reply #195 on: April 27, 2010, 02:28:18 pm »
Clear your head and look at it again. What brand TV?

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Re: How to use SCART for our hobby
« Reply #196 on: April 27, 2010, 02:42:44 pm »
Clear your head and look at it again. What brand TV?



It's a Roadstar CTV1020. It's only a 10" screen which is perfect for the bartop.

EDIT: I'm beginning to wonder if this TV doesn't accept RGB signal... only composite. I can plug my Skybox in to the TV and get a picture. Skybox is set to RGB but would I still get composite signal if the TV scart didn't accept RGB? I was also able to plug XBox360 into it and get a picture.

Any sure way way to check if the scart does accept RGB or not? I don't have a manual or remote control for this TV unfortunately.

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Re: How to use SCART for our hobby
« Reply #197 on: April 27, 2010, 06:37:54 pm »
It happenned to me once: A Goldstar (= Sh!tstar) branded TV with SCART input that only accepted composite through pin 20 - ARRRRRGH! Your Roadstar sounds suspiciously similar.

I think that the only way to be sure is to whip the back off the TV and see if you can trace any RGB signal lines going from the SCART into the video input stage.
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Re: How to use SCART for our hobby
« Reply #198 on: April 28, 2010, 12:00:21 pm »
It happenned to me once: A Goldstar (= Sh!tstar) branded TV with SCART input that only accepted composite through pin 20 - ARRRRRGH! Your Roadstar sounds suspiciously similar.

I think that the only way to be sure is to whip the back off the TV and see if you can trace any RGB signal lines going from the SCART into the video input stage.

Well I wouldn't know how to do that really. I can tell you that I tried the bartop on the main TV in the house (38" Samsung) and this has two scart sockets, one of which is clearly labeled "RGB". But I still get the same result... a black screen. I was expecting it to work on the Samsung tbh, which would have confirmed my fears over the Roadstar. It should at least work on the Samsung surely?

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Re: How to use SCART for our hobby
« Reply #199 on: April 28, 2010, 07:09:47 pm »
Yes, if the cable is good then It should work on the Samsung, assuming that you have the TV in the right video mode etc ... although the cable itself should auto-select most of this.

If you like, I can make a cable for you for a fair price + shipping. The cable would be fully tested with multiple SCART TVs before leaving my hands. If for some wierd reason it doesn't work for your equipment, you can return it to me for full refund (less shipping) within a reasonable period. However, I have never had an unhappy customer.

Your VGA-SCART cable would have a molex plug for 5v & 12v input from PC, and look something like this:


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