Commodore1084s-d1 monitor sync problems with pce

[seefuu1]

Hello there people,seeing as this is thee place for all things engine related,i'm sure you'll have come across my problem before and can help me out.

I have myself a briefcase setup,and i've recently installed the  RGB mod and amp based off of the mmmonkey guide @mmmonkey.co.uk(new 8 pin mini din,removal of the rf modulator)inside of my pc engine,and yesterday i managed to get myself an commodore amiga 1084s-D1 monitor PAL version,the one with the 9pin d-sub socket,and i have wired up a d-sub plug following this pinout http://www.zimmers.net/cbmpics/cbm/monitors/1084s/pinout.html ,with the R-G-B ,composite video to the composite sync pin and ground to the d-subs 2 grounds and all i've got is a picture that can't sync.

So i tried the resistor fix on the sync/composite video line,and the closest to a stable picture i get ,is with 400ohms in series,and this is with dynastic hero on the title screen(but the colours are not correct somehow ),stick in shinobi with it's moving title screen and the sync problems come back,any moving on screen action and the monitors goes haywire again,sometimes all the colours except red will go,then everything but green will go,i've also tried with a pot,but this was 50k and trying to fine tune this was a right bugger,and when i did get a stable picture again with dynastic hero ,this just went off sync again when i used anything else with movement.

After 5 hours ,this is what i've tried and failed with,combinations of all;

Put an amp on the consoles composite video line

Put an amp on the consoles comp sync line

Added 75 ohm resistors on the R-G-B lines

Various resistors on the comp sync/video line with and without an amp.


It seems a lot of people have had problems with these monitors,so i'm just wondering if i should just get rid of this model ,along with the head aches and get the normal 1084/s.

fraser


 

[seefuu1]

http://www.atariage.com/forums/lofiversion/index.php/t91644.html

I've been trying to get a 1084DS to work with composite sync going in on pin 7 and had no luck. I googled around and found this thread talking about how some 1084's just don't take composite sync. I tried feeding it to pin 9, both pin 7 and 9, but nothing worked.

So I took a look at the schematics and did some experimenting. I finally got it to work by doing a slight mod to my monitor.

I put a jumper across pins 6 and 10 on the chip labeled I202 (a 74L506). After that, I put composite sync to both pins 7 and 9 on the 9 pin connector. That worked very well. Here's a picture of the jumper I made

[Arkhan]

Ewww commodore hardware with PCE? Thats like blasphemy.

[Ravij]

Hi,

I have the same monitor (somewhere - I haven't used it in years!)

The problem with this monitor is that you can not take the Composite Video and use that on the Composite Sync input, as the additional video signals confuse the monitor. It expects to see just sync signals.

There is a fairly simple fix, which involves using an off the shelf IC (chip) to strip out the Sync signal from the Composite Video.

The chip needed is LM1881. This used to be fairly easy to obtain (10 years ago) but I'm not sure any more.

http://www.gamesx.com/misctech/lm1881.htm

Circuit details are there. It's a very easy circuit to build, and you should be able to power it off the +5V output from the PC Engine video port as well.

If you have any other questions, let me know.

[TR0N]

Ewww commodore hardware with PCE? Thats like blasphemy.

Not realy i use one for my duo-r and the picture is realy sharp.Compare to if i run it on the tv where details are lost and the colors look washed out  I've also find it's sweet for using the,famicom on it as well since the montior suports composite.

Btw mine is the 1702.

[pcenginesales]

I had this monitor years ago, bloody annoying monitor. I could never figure out the sync issue because back then there wasn;t enough data on the web so I thought it used the regular Amiga monitor pinout which takes sync off the composite IIRC, this monitor doesn't.

I NEVER got the PCE working with it but I never tried just pulling sync directly from the PCE board. There's a sync pin on the rear connector as well as a composite pin. Now it may need amplifying with the usual transistor and it may not, no clue. The details are on www.gamesx.com anyway, including the amp for the sync that the monitor may need.