Star Wars Spot Killer On

[fmarkus]

Hello,
I'm the proud owner of a magnificent Star Wars cockpit that I have enjoyed for a few years but unfortunately, the screen has just turned off and I have no idea why...
I have read the forum and checked a few things:

- Games runs without the screen. I can hear it and interact.
- Power still seems to be going to the screen: typical sounds when turning on/off.
- Spot killer is on...
- If I adjust the screen intensity I can only see a green dot on screen.

Do you think the screen is still ok? I read somewhere that there are regulators that can fail and trigger the spot killer but... I can't seem to find these regulators. I read they are on the chassis itself but I have no idea where to look... Are they on the deflection board?
Any help would be greatly appreciated. I miss my game

Fred.

[fmarkus]

So it seems that the transistors that might be the issue are on the deflection board and another board on the left of the screen, right above the main fuse box... I can count 6 of them, with a TO-3 form factor: 4 on the deflection board, 2 others on the other board.
I'm looking for q102/q103 per this document: http://repairfaq.ece.drexel.edu/REPAIR/whole/F_VAtari.html#VATARI_028
Can anyone tell me if I am wrong and if not, wish one is wish since the drawings and what I have doesn't match?
My deflection board is like this one:
http://www.quarterarcade.com/GamePicture.aspx?c=&g=7394&o=0&m=0 (But mine has the transistors
Any help would be greatly appreciated.

Fred.

[RayB]

A Star Wars can come with one of two different monitors: Wells Gardner (6500 I think), and Amplifone. You should make sure you are referencing the correct info for the correct monitor.

Other than that, I am anxiously awaiting a response to your thread too. Sorry I can't be more help. (Though from what I have read, the spot killer can come on if the monitor is not getting any signal. Did you test the game board's XY output? The special Atari video chip is known to die.)

[ChadTower]

The spot killer indicates an out of range signal.  That can be a bad signal or none at all.

[fmarkus]

Actually, I can only see 4 TO-3 Transistors, all 4 on the deflection board.
I have tested them and they seem ok. Problem must be coming from somewhere else...
Question:
Where are the remaining 2 TO-3 Transistors?

They could be the problem...
Thanks for the help!

Fred.

[RayB]

If memory serves correctly, there are some mounted directly to the monitor frame.

[ChadTower]

Step 1 is to verify the voltages off the test points in the vector gen section of the game PCBs.  You can chase this around the monitor forever if the problem is on the game PCB.  It's pretty common for an op amp to fail in there and cause the monitor to spot kill.

[fmarkus]

ChadTower, that sounds like the right thing to do. I only have a digital multimeter. Will this be enough?

[fmarkus]

RayB, I can't see these... You mean on the tube itself?

[RayB]

Here's a photo I nicked from this thread:
 http://forum.arcadecontrols.com/index.php?topic=90963.80



If you look at the frame itself, on the right side you can see 2 transistors mounted to the outside of the frame.

I don't know what brand of monitor that is, the amplifone or other (Wells Gardner or Electrohome).

[fmarkus]

Thanks for the picture. Mine doesn't look like that at all. I will post tonight. I can only find 4 of them on the deflector board. THe chassis is in wood and I can't see any other ones around...

[RayB]

Yours is probably an Amplifone then! Lucky you.

Here is an FAQ for it : http://gamearchive.askey.org/Video_Games/Manufacturers/Atari/monitors/amplifone/amplifone_faq_1_2.pdf

[ChadTower]

ChadTower, that sounds like the right thing to do. I only have a digital multimeter. Will this be enough?

Yes.  You'll have to look up exactly where on the Star Wars boardset the vector gen section is but you'll see test outputs for X out and Y out.  Maybe one for each color, it's been a while since I looked at a color boardset and spent a lot of time on black/white boards lately.  What you're going to do is hook your red lead to X Y or Z out, black to the closest GND test point, and set your meter to DC.  If you see it stay at or very close to zero constantly then you are missing one of your outputs.  That is a common cause of a good monitor spot killing.

Sorry it's not more specific, I only have one Star Wars boardset and I don't have physical access to it right now.

[fmarkus]

You have no idea of how good it feels to get some support
Thanks guys!
 
I will find and test the x y z out tonight. Can't wait to go home and try!

[fmarkus]

Just went through a bunch of tests, here is my report:

Extracted main boards
Found Xout, Yout, Zref, R/G/B pins (Man these boards are so well designed...).

I get variations both in AC/DC on Xout/Yout. Around 2v in AC.
Looks like fixed on Zref at around 5v AC.
Found +15v, -15v, +24v, -24v around the board. No problem there it seems.

Close to the R/G/B pin outs, I found a +12v pin out there. NO voltage there at all. Don't know if this is normal...
R/G/B all give me 0 in AC. 0.08 in DC... With an LED turned on right next to the R/G/B pinouts.
Is this normal?

Fred.

[fmarkus]

Looking at the schematics, it seems that 3 transistors should be getting 12v for each R/G/B signal... No 12v, no signal... Maybe I'm getting close. Will test again tomorrow morning.

[fmarkus]

After some hunting, I found out that the 12v was not arriving at the boards bridge... I looked into the connector... pin bent...
Some screwdriver work, Power on, spot killer turns off and...
SCREEN ON!
My game is back! Haven't played it in 5 years!
Thanks for the help all!

Fred.

[yotsuya]