Started by nightmarez, March 20, 2006, 03:32:52 AM

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Hi to all!

I've got a Commodore 1084S-P Monitor.

I tried to connect game consoles to it (neo geo, snes, gamecube...), connecting appropriate pins of the DIN 6pin connector.
(I connected rightly R,G,B,GND,CSYNC)

Nothing to do! Image is unstable!!!   WHY???????
While connecting an Amiga (500,600...) it works fine!

I found a .doc for adding a SCART connector to the monitor.
I read with a SCART connector I'll solve my problem.

Did anybody perform this mod?



This is a philps monitor isn't it? If so then it's easy to make a SCART adaptor for it.

[SCART > monitor]
video output > rca video input
red, green, blue output > red, green, blue input through 6 pin din
connect all the SCART ground pins together > din 6 ground and rca video sheild

I don't think it needs any internal modification.


Hi, thank you for reply.

Do you mean a SCART adaptor? (no adding a SCART Connector, right?)

How can I select the SCART Input with the switches on the monitor?

By this connector, do I solve my problem? (image unstable)

(I read something about the inverted Csync signal, which cause the problem...)


"Do you mean a SCART adaptor? (no adding a SCART Connector, right?)"

Yeah, an external adaptor. Like a box with a female SCART connector on it that has cables coming out to go to your monitor.

"By this connector, do I solve my problem? (image unstable)"

I was talking to someone about t year ago who had the same problem with a simillar monitor, a daewoo 1084. His Amiga worked fine but the composite sync from game consoles (snes and genesis) would give an unstable image. The soultion was to modify the monitor to sync from the video input while displaying video from the RGB input.

I'm pretty sure your philips monitor can sync from the video input without any modification. You can can just select RGB mode and get a stable picture. I've got one of these monitors at home so if you can wait a couple of days I can check for you.



I tried your mod:

R,G,B,GND to  DIN 6 pin
CSYNC     to  composite video input.

With the monitor in RGB mode I continue to get an unstable image. (same as I get with the Csync directly to DIN pin)

With the monitor in CVBS mode I get a b/w image, as if RGB signals don't pass if switch is in CVBS mode).
In this case, I tried to remove R,G,B signals and I get a b/w image, too.

What is the real problem?
Why I get the unstable image? (and NOT with the amiga?)

On the web I found this info to add a SCART connector to the monitor (it would solve the problem).
I use "cut and paste":

Note: we thought it would also work on the MSXturboR, since it's RGB connector is very similar to the one in the Sony 700 series. But it did not work! To let it work on an MSXturboR, we recommend to build a SCART connector into the 1084s. The monitor is prepared for this. The drawback is that you need to do quite some modifications. To make those modifications, you have to look carefully to the instructions on the circuit board. This is how Saku Taipale describes it:
There is a set of jump wires in the monitor and some of them are left away from the 1084 which doesn't have a scart connector. Jump wire connection points are marked as a line from hole to hole in the board and are also numbered.

I connected these wires: 9202 9206 9212 9247 9270 9274 9275 9289 9290 9331, R533 (this is a place for resistor, but I put wire there instead).

Connect these connection points with a long wire (they have triangle marked in the connection hole):
24 - 49
22 - 50
69 - 44

Next: the resistors. Here is the list of resistors with the values (in Ohm) I used, the code in mainboard is same Rxxx.
code   value           code   value
R210   22   R403   39k
R220   75   R502   100
R303   22k   R504   390
R304   15k   R530   1k
R305   5.6k   R537   4.7
R306   5.6k   R538   10k
R307   18k   R541   15k
R308   100k   R548   68
R309   15k   R545   39
R310   47k   R546   150
R311   100k   R547   39
R312   47k   R551   1.2k
R313   15k   R563   5.1k
R314   1.5k   R624   10k
R315   15k   R625   100
R402   4.7k   R626   2.2k

Capacitors, marked also in the mainboard, just find the right places...:
code   voltage   value   remark
C308   50V   1uF   
C312   16V   10uF   
C313       560nF   (?, has mark B561 in it)
C314   16V   47uF   
C315       220nF   
C401   25V   2.2uF   
C537   16V   47uF   
C544   16V   22uF   
C545       68nF   
C548       680nF   (?, B681)
C568       22nF   

code   transistor type
TS310   C548B
TS313   C548B
TS315   C548B
TS405   C548B
TS544   C548B

Diodes: D601 D602 D603 D604 D605.

And also, remember to buy the male (90 degree turn in the legs) scart-connector for your modification!


QuoteWith the monitor in CVBS mode I get a b/w image, as if RGB signals don't pass if switch is in CVBS mode).

Ok, it looks like your monitor can't sync from the video while displaying a picture from the RGB input.

I think the reason why it didn't work in the first place is that the signal you refer to as Csync is in fact CVBS (composite video). A SCART cable does not carry a Csync signal at all.

To connect game consoles to you monitor you can:
--Build cables with a Csync signal available.
--Use an LM1881 sync seperator IC to convert the CVBS into Csync. There's a page on with the details.
--Modify your monitor slightly -- it was something simple like cutting a trace and adding a jumper wire. Then hook it up as I discribed above. I'll find the info later.
--follow the doc file instructions???



ok, but I used pure Composite-sync of my neogeo (pin 7 of the DIN 8 pin connector of the neo geo is Csync output).
I didn't use the composite-video output.

Then I think the first 2 solutions to the problem aren't good. (it's true?)

I could try to use an LM1881, but I already have a csync output!

However, it's strange that connecting only CSYNC and GND I got b/w image!
I think csync signal wouldn't carry a b/w image, but nothing!

What about the modify of the monitor?

And what do you think about the mod for adding a SCART connector, I found?


I've had a poke around in my monitor and have some good news. The mod is...

Remove TS509. It's a BC548 transistor located on main board (it's to thel left, under the power supply board). It's job is to short the video input to ground (that's bit rough on the video signal) when the mode switch is in the RGB position.

btw. composite sync (through the DIN pins 2 or 6) works ok on my monitor.


I removed TS509, but wothout result.

in CVBS mode no image on screen (both with csync on DIN 6 pin and with csync on compvideo input).

In RGB mode image is VERY VERY UNSTABLE, both with csync on DIN 6 pin and with csync on compvideo input and WITHOUT any csync applied!).
Same results in the 3 cases! (same images on the screen)
It seem as the csync input of the monitor is shorted to GND.

With the TS509 image was unstable, but without is VERY VERY unstable (csync not present).

Help me!

Is the TS509 connected to your monitor? (or did you remove it?)

HAve your monitor the SCART connector?


No, don't use Csync! Use composite video!

Connect the composite video signal to the usualy yellow connector, switch the monitor into CVBS mode and you get a good, stable picture don't you? If not then it's probably better to give up now. If you do get a good pic then connect the R, G and B up to the DIN6 and switch to RGB mode...and it should work ok...

My monitor no longer has it's TS509 and it's the version without the SCART (though there's a space for it on the PCB). I've also got another monitor of the same model with a SCART connector.


Ok it works!!!! THANKS!!!!!!

In RGB mode, with RGB and GND connected to DIN 6 pin and with composite video (or with the csync!) to the CVBS input, i get a PERFECT image!!!!

In CVBS mode, I get a b/w image.

Could you help me now for this?
I tried to connect a PCengine console (which outputs R,L audio and composite video), I get a b/w image.
But I know this monitor supports both PAL and NTSC mode!!! (then It would display the colors!)

I'd like to add the SCART connector to this monitor (as PCB supports this).
Do you know the infos I wrote on the top of this topic are correct?
Could you take a look between the 2 1084 variants  you have? (with and without the SCART)


I had a quick look in my monitor again and it looks like the SCART input is all ready to go. Just add a female SCART connector to the PCB and a wire link from SCART pin 20 to the composite video input and you're set.

Something cool I've just noticed about this monitor is that when it has R504 fitted (going by the values in the .doc file) pin 20 is not a standard video input but a kind of all purpose video/sync input. You can connect either video or TTL composite sync and fully expect it to work.

If you like you can put in a few more bits and get the auto-switching to work (follow the trace off SCART pin 16). Then you can put TS509 back in....though I don't think it's worth bothering about unless you want to hook two devices (one CVBS, one RGB) up to the monitor at the same time.

As for the picture being not having any your CVBS/YC switch in the right position? My monitor is PAL only but there seems to be empty spots for NTSC decoding stuff on the board.


I switched my monitor in CVBS position, but image is b/w! (with a Jap PCEngine connected)

My monitor is PAL, too.

How can I solve this problem?

Thank you


If your monitor is PAL you will only get a black and white picture with from a JAP PCengine via composite video.  

To get color from the PCengine on that monitor you will either need to use a NTSC to PAL converter (easy, but poor picture quality), or modify your PCengine to output  RGB (more difficult, but best picture quality).

Information on adding an RGB output to a PCengine is avaible on the main gamesx site.


Ok, I took R,G,B,Csycn on the outside of the console and I connected them to the monitor.

It works (I get a colored image), but colors seems to be a bit dark.

And if I connect the console via RGB to my TV colors, image isn't persistant on the screen.
(image appares, but quickly the screen comes black; then reappares and another time black....)

It seems as the signals aren't enough high in level (I think!)

How can I solve this?



if your commodore 1084s is the same as mine (mines pal) then it has a 9 pin rgb connector for video. it uses composite sync, and cannot accept composite (scart uses composite) video as a sync source. all you have to do to make it work is built the lm1881 sync separator circuit and use composite sync from that. i dont know what you were trying to do, i didnt read thoroughly, but this is all you need, you dont need any components on the video lines at all. i actually built an adaptor to go the othewr way. i made all my rgb cables to plug into the 1084s, and made a D>Scart adaptor for my 1084 (which has scart) since all my 1084s cables needed composite sync, and my 1084 needed composite video, i had to add a capacitor and i think a resistor to the sync line to bring it down to the composite video voltage levels. i added a switch to bypass these because my saturn cable for some reason didnt work with the components there.

i think i lost my way a bit there.. in the end, research the lm1881 sync separator. i think theres a schematic for the circuit on gamesx.