Cinematronics vector monitor no vertical delfection

bjk7382

New member
Joined
Mar 1, 2005
Messages
832
Reaction score
2
Location
Dorr, Michigan
Cinematronics vector monitor no vertical delfection

I have a Solar Quest I have been trying to get going. I am one step closer. I have (what I think) is a working board. This was an Armor Attack board I got off of ebay. I got it in the mail and plugged it into the solar quest and I had it fully playing blind (could hear the tanks, helicopter, ect) I couldn't control it cause I think the controls are wired differently. But then I swapped the board over to solar quest and found that I don't have a working sound board (one has a short and the other only makes random sounds when the buttons are pressed.

It does look like the game is playing in the line, but I am hoping that this is some simple monitor fix and not a gameboard repair.

Anyone care to take a guess as to where the problem may be on the monitor? I have checked about every diode and transistor on the thing (including the ones on the heatsinks) and can't find any bad parts. (I have a second monitor that blows the circuit breaker in the game instantly when powered up)

The noise in the very beginning of the video isn't the game (not sure what it was)

 
Yeah, these are by far the hardest games to fix since nobody seems to know much about them. The manual is so in depth that it goes right over my head. I just went thru wysiwyg's website and ordered all those parts to shotgun both of my monitors. I also plan on sending my game boards off to him to be repaired since I have 2 that do nothing but a solid led.

I would like to know if this problem I am seeing with my "working pcb" could be the PCB or not, from what the manual says it is sounding like a monitor problem.

And in my looking at the schematics and manual it seems like I might have a problem with the +15 or -15 voltage regulators, and/or ic1 on the monitor.
I replaced the sockets on ic1 and the 2 dac's with no change, as well as checked the yoke for open windings, and checked the external amplifier transistors on the heatsinks

I am just glad it is firing up without blowing the breakers, feels like some good progress to me after seeing it sitting doing nothing for 2 months or so.

I am getting ready to rip the harness and everything out of the cabinet and put it on my workbench to make testing things easier.
 
Had a similar issue with the monitor in my Starcastle - problem was cracked solder joints on the deflection header on the monitor board.

Pull the board out and re-flow the solder joints on the deflection headers (both Horizontal and Vertical) with nice fresh solder and see where you are at after that.

RussM


I have the same thing going on with my Starcastle can anyone help us?
 
Had a similar issue with the monitor in my Starcastle - problem was cracked solder joints on the deflection header on the monitor board.

Pull the board out and re-flow the solder joints on the deflection headers (both Horizontal and Vertical) with nice fresh solder and see where you are at after that.

RussM

Thanks Russ I'll give that a shot.
 
I got my problem fixed today after changing the transistors on the monitor board.Both vertical and horizontal sections were replaced.
 
glad you got it fixed... the heatsink transistors are the first things I replace ('cause they're the easiest :), but as was mentioned, don't ignore the solder joints on the cable pins. A whole lot of data goes across those ribbon cables. You should reflow them on all your Cine boards.
 
Russ's suggestion to reflow all of the molex headers on the monitor board was very helpful. You can do the same thing on the 34-pin IDC header on the monitor and also on the CCPU. In this case, I'd bet that the problem is on the monitor board and not the CCPU board.

Possible problems that cause vertical deflection loss:

1) Bad ribbon cable, loss of several control signals. I doubt that it is this however since to have no vertical at all, about half of the cable signals would have to be missing entirely. Since horizontal seems to be working okay, I'd say the odds are that the ribbon is okay. Sometimes corrosion occurs within the teeth that dig into the cable insulation right where they meet the wires. This can be hard to see without taking the connectors apart.

2) Bad power transistors on the heatsinks. Try unplugging them and see if the picture comes back. I know about the warnings but don't worry about it. Just make sure that you only run it that way for a moment or two so that it won't overheat the driver transistors on the board.

3) Open deflection coil. Unplug the yoke and measure the coils at the molex connector. I think they are something like 1.5 ohm and 0.7 ohm or thereabouts.

4) Bad DAC80. Swap the DAC chips and see if the line goes vertical.

5) Bad quad switch chip at IC1. The LF13331 chip might be fried. All you can do with that is replace it.

6) Bad 8-pin TL081 op-amp. Replace IC102 and IC202.

7) Bad driver transistor or shorted diode/s on the board. While it is possible to scope out root cause, I suggest simply replacing all transistors and diodes (and caps). It's maybe more work and a little more money in the short term but in the long term you get a much more reliable monitor for your efforts.

8) Check pots R102 [5k] and R109 [100]. These control vertical line length and picture size respectively. One of these pots might have an open wiper or something.
 
Thanks for all the suggestions. I am currently waiting on the big parts order for my 2 monitors (pretty much every part on wysiwyg2's website, except for the pots and heatsink transistors I will get from bob)

So when this order gets here tomorrow I will be replacing all the caps, diodes, transistors, ect. and hopefully that will fix my problem as well.

I will be trying some of the suggestions from Bill too before the parts get here. Such as swapping the DAC and lf13331 chips around from monitor to monitor and see if it changes.

Wish me luck...

Oh, and I am pretty sure that the problem is in the monitor now. I tested the output of the ribbon cable going to the monitor and I get fluctuating dc voltages on every pin (this means that data is being sent to horizontal AND vertical dac's right?) All I got is a multimeter though, no logic probe or oscope.
 
Be sure to post with any progress when you shot gun those parts. I'm probably in the same boat and need to stop procrastinating and fix mine.

Good luck.
 
If any of the transistors are bad on the heatsink, it's very likely that the 47 ohm resistors by the connector to the the heatsink are shot too. Usually they burn up enough to be obvious but sometimes they look fine. The Tantalum caps tend to short too when the transistors burn up.

If you look at the schematics for these monitors, after the DACs they are pretty much just a two stage audio amplifier connected to a picture tube. I don't know why but after I realized that they became a lot easier for me to troubleshoot. You can disconnect the yoke, power them up and follow the signals through.
 
Russ's suggestion to reflow all of the molex headers on the monitor board was very helpful. You can do the same thing on the 34-pin IDC header on the monitor and also on the CCPU. In this case, I'd bet that the problem is on the monitor board and not the CCPU board.

Possible problems that cause vertical deflection loss:

1) Bad ribbon cable, loss of several control signals. I doubt that it is this however since to have no vertical at all, about half of the cable signals would have to be missing entirely. Since horizontal seems to be working okay, I'd say the odds are that the ribbon is okay. Sometimes corrosion occurs within the teeth that dig into the cable insulation right where they meet the wires. This can be hard to see without taking the connectors apart.

2) Bad power transistors on the heatsinks. Try unplugging them and see if the picture comes back. I know about the warnings but don't worry about it. Just make sure that you only run it that way for a moment or two so that it won't overheat the driver transistors on the board.

3) Open deflection coil. Unplug the yoke and measure the coils at the molex connector. I think they are something like 1.5 ohm and 0.7 ohm or thereabouts.

4) Bad DAC80. Swap the DAC chips and see if the line goes vertical.

5) Bad quad switch chip at IC1. The LF13331 chip might be fried. All you can do with that is replace it.

6) Bad 8-pin TL081 op-amp. Replace IC102 and IC202.

7) Bad driver transistor or shorted diode/s on the board. While it is possible to scope out root cause, I suggest simply replacing all transistors and diodes (and caps). It's maybe more work and a little more money in the short term but in the long term you get a much more reliable monitor for your efforts.

8) Check pots R102 [5k] and R109 [100]. These control vertical line length and picture size respectively. One of these pots might have an open wiper or something.

Thanks for taking the time to share all of that wysiwyg2 :).
 
Where's the best place to buy a Dac 80 chip? My screen was drifting to the side so I switched dacs now it drifts upward.
 
Alright got the parts in and installed them all. Major pain in the ass, and it still doesn't work... gotta love cinematronics.

I actually may have taken a step back with it. Now that the parts are in it blows the first circuit breaker almost immediately, but the second one holds. You can hear a little bit of deflection before it goes.

If you unplug the yoke and fire it up then it doesn't blow any circuit breakers and runs with the dot in the middle of the screen (don't worry I didn't leave it running more than a few seconds to see if the breaker would blow or not. I'm not going to burn the screen up)

I need to go back and check my work in the yoke area and see where I went wrong. Pretty frustrating since I went really slow and double checked everything as I did it and then double checked it all again after the fact... must be something I missed though.
 
A bad dac can cause the breaker to trip.

They are the same dac's that were in there with the horizontal line and no breakers tripping, in the same position too. I did swap them, but they are back to where they were now.

I did just have it back apart and found a bad transistor at Q109, which I already replaced once. So I will be checking for any more problems around that too.
 
Where's the best place to buy a Dac 80 chip? My screen was drifting to the side so I switched dacs now it drifts upward.

Digikey has them in stock:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=ADDAC80NZ-CBI-V-ND

Newark has them (ignore the skinny-dip pic, it's wrong, device is corrrect)
http://www.newark.com/analog-devices/addac80nz-cbi-v/d-a-converter-d-a-ic/dp/12M7687

Arcadechips has them but you might get old stock. The above sources are brand new parts.
http://www.arcadechips.com/product_info.php?products_id=98
 
Put the new Dac in and now the picture stays put, only problem is its not centered it's off about a 1/2 inch. Any Ideas? Sorry I'm not trying to hijack your thread.
 
Back
Top Bottom