Need Help Syncing Exidy Targ to a G07-CAO Chassis

Parpunk

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Ok guys i hope someone can help me out here. Im still a bit of a newb but i just rebuild my G07 in my TARG. (new flyback,all caps, hot, regulator) Well when i hooked it back up i was getting horrible scrambled images. So i thought i had a chassis problem so i sent it out for repairs. Well i get it back when its supposed to be working 100 percent and im getting the same problem i had before so i now believe i defintly have a sync problem.

After checking out the setup on my TARG machine it looks like the red green blue sync etc. all comes from the little board below the PCB. And i took some pictures of the way it is currently hooked up. One thing i noticed is the where the pins are labeled on the board it looks like on the connector someone skipped the wire that says C sync and dropped the wires down a slot which (to me) looks like the bottom one isnt making contact with the labeled pin on the board.

So couple questions here, does anyone see anything wrong here, and anyone have an idea of where each wire goes to the 6 pins that are on the video board on the G07 CAO chassis. Thanks!

Below are Pics of the way it is currently hooked up, also a pic of the 6 pins on the video board on the chassis 1-6 (unfortunately none of the wires are really colored either.) And also i included a pic of what my screen looks like. i can never get it to stop scrambling much.

100_0665.jpg

100_0666.jpg

100_0667.jpg
 
I think I remember somebody telling me that the C-sync is some kind of composite output, and that it's not needed for standard RGB monitors.

Ahah! Found the qoute I'm referring to, it's from Cwilkson:

"That's probably composite sync. It's the combination of H- an V-syncs. It just allows more options for monitor connections. Ie...you should be able to connect that to a regular TV monitor with RGB inputs.

If your monitor has H- and V-sync inputs, you can use those and ignore the C-sync ouptut from the board. "
 
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ok thats good info. but judging from the first picture does it look to you like the pins in the connector are connecting to the h sync and v sync correctly? To mke it looks like they skipped the c sync and then moved the three wires down.?
 
Definitely missing a ground pin...

Its going to be either set of these

R G B HS VS GND

or

R G B CS GND

That bottom pic? Is that the monitor? Doesn't look like a G07... is it the old monitor chassis?
 
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ok i wont have time to check it out tonight so if you can check out the spectar tonight that would be MUCH appreciated. As far as the monitor goes yea its a G07 but with the CAO chassis (the older chassis)
 
Have you tried adjusting the H-hold pot?
It looks like a simple adjustment which is common after a cap kit. I think your plug looks good, you have RGB hsync vsync and ground all present.
 
BTW would i run the ground to the pin underneath the v sync pin???

I'm not sure on that version... on mine, looking at the connector from right to left its R G B G VS+ HS+ and there is a separate one for VS- and HS-

So my guess is:

1 = RED, 2 = GRN, 3 = BLU, 4 = GND, 5 = VS+, 6 = HS+

On your board its clearly labeled except for the GND pin which I would suspect is pin 7.

Monitor Pin 1 > Targ Pin 1 (R)
Monitor Pin 2 > Targ Pin 2 (G)
Monitor Pin 3 > Targ Pin 3 (B)
Monitor Pin 4 > Targ Pin 7 (GND)
Monitor Pin 5 > Targ Pin 5 (VS+)
Monitor Pin 6 > Targ Pin 6 (HS+)

I'm probably screwing this up...
 
ok got the CAO manual and yead its rd, gr, blu, grd, v sync, and h sync (left to right)

So after checkin it IS hooked up correctly. I try adjusting the H freq pot and it helps a little but is also making a whistling sound when i turn it left to right. Anyone think this pot would be bad? I just had Peale do the repairs and he sent it back to me "supposebly" working 100 percent and feel if the pot was bad he would have replaced it but it wasnt replaced. Any thoughts here?

All im getting is these crazy scrambled images and the picture will never settle down no matter what i adjust?
 
This is a G07-CAO that was sent to me non-working. The B+ voltage was reading ~150VDC. Replaced the voltage regulator and the HOT blew. Replaced that and I had had stable voltage, but no heater/picture. After a couple minutes, it fired up, but with an out-of sync picture.

Figuring some kind of thermal fault due to a broken solder joint, I sat down and touched up every solder joint on the board (there were about ten million broken joints on the board) and I got a good image - but one that just wouldn't lock on. Suspecting a problem with my test rig, I did connect a wire bridging the H and V syncs together on the bottom of the interface board (you can see the black loop of wire in that first photo of the chassis) and it snapped to a perfect picture.

Wanting to make sure the slow start issue didn't reoccur, I started it dead cold every morning for about a week and a half, and ran it for about 1/2 an hour before shutting it down for each day. Finally, I called it a "win" and shipped it back to him.

I informed him of the wire loop under the interface board, and that if he had any issues that clipping it may solve the problem on his end (since I had no way to test it on his end, this was the best I could do).

In those photos above I'm not seeing a video ground, unless I'm mistaking it for something else. I see R, G, B, C sync, H sync and V sync.

edit: looked over the image again, and yes, there is a video ground.

You said you stopped when it started "whining" - did you turn past that whining point, or did you just stop there and turn back?
 
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Have you tried adjusting the H-hold pot?
It looks like a simple adjustment which is common after a cap kit. I think your plug looks good, you have RGB hsync vsync and ground all present.

X2 on this advice. It looks like it just needs the H-hold adjustment pot tweaked. If that doesn't work, then try relocating the pins as others have suggested.
 
ive tried adjusting the H freq pot and it never stops going nuts. It actually looks exactly like that video on youtube of someone's Frogger that was going nuts on the screen. Anyone see that?? Looks just like that.

http://www.youtube.com/watch?v=pEFRAVv_yXo

i dont see where there is a H hold pot? Maybe im missing something here? i just see in the bottom right corner vertical size H freq, etc. i think there might be a vhold too.

That frogger video claims to be a board problem, so i have a spectar board im gonna try in it today to see if it will rule out the thought of being a board problem. Looks like a bad sync problem to me but who knows. Ill keep ya posted and if anyone has anymore ideas throw em my way.
 
H Hold = H Freq. Some combo of H Freq and V Hold I'm sure will nail this down, assuming the board is otherwise working. It was working perfectly here.
 
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I GOT IT!!

Im gonna say 2 words that dont get used enough around here.

TUNING SPRAY

Whoever works on a monitor that has the old metal pots used for adjusting a monitor needs to go to radio shack right now and get some tv tuning spray. It was a 10 dollar fix for me.

So i went to radioshack today because i was on a hunch the pots will not adjust and were not working the way they were supposed to. So i spent 10 bucks on some tuning spray hoping this was the problem. got home and blasted the vertical hold and H freq pot like crazy. Let dry blast again and again. Fired her up and it seemed to be working much better but i still could not get the picture to lock.

Discharged the monitor, unhooked it, pulled the chassis and found the black wire loop mod peale did. (the wire that was connecting the h sync and v sync (pins 5 and 6) Cut it, put it back in and within 1 minute of adjusting BOOM picture locked right in looks great, and i then spent the rest of the afternoon rocking out on spectar! YAY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

So for future reference tuning spray works wonders and make sure to reccomend it to anyone before they send a chassis in for repairs lol. Come to find out im sure this was all it really needed berore i sent it away for repairs. (well it was all it needed before i starting turning knobs without reading the manual first, and then cranked up the B+ to 150vdc and runined my Hot or VR (one or the other peale had to replace.)

thanks again everyone for the help.
 
Tuning spray may have cleaned the pots a bit, but it was clipping that wire loop that allowed it to sync. And your other problems were the 10,000 broken solder joints.
 
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