Tempest monitor shows "1/2" the game screen.....

S4Patrick

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Tempest monitor shows "1/2" the game screen.....

Hello...

I'm getting closer and closer to FINALLY fixing my Tempest game that's been a tremendous challenge.

Just got my monitor boards from Chad @ ArcadeCup and install them back into the Tempest. Chads work looks rock-solid.

The Tempest screen only shows 1/2 the game screen. Please take a look at the attached pictures.

What's the current issue that I'm having? Is it an adjustment I need to make or is it something more?

The red, blue & green on the screen are all there, nice, bright, and vivid. The Main PCB's & power regulator board have been tested in another Tempest game and work 100% fine.


I'm not to knowledgeable about the detailed workings of this game, but know where everything is at.


Thanks everyone!
 

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you need to change one of the frame mounted transistors.


it is that simple. look on bob roberts website, he probably has a very good how-to.



someone better than me can tell you exactly which one I am sure
 
Yep, probably one of the bottle cap transistors mounted on the frame under the deflection board. Has the monitor been caped and an lv kit installed on th deflection board too.
 
Hello and thanks for the replies....

As for the transistors, I have changed them all when I 1st started having monitor issues, but to no avail. I also put in new mica plates underneath the transistors---that was almost 2 years ago which is when my Tempest first started to fail.

I have been slowly "fixing" everything on the Tempest. The PCB's and regulator board have both been sent out to Electon Forge, and Alex here on the forums. Also, I have indeed had the monitor boards recapped, as well as having an LV2000 installed. I've replaced big cap on the power supply with a Bob Roberts one. I also changed the wire harness with a different one. I'm getting closer to having this game play correctly. It' should be near bullet-proof with all that I've had done to it.

I know where the transistors are located, perhaps I should "re-seat" them?

Any other tip or perhaps the exact transisitor I need to go after?

Thanks!


~Patrick
 
Reflow the solder on the bottom of the frame mounted transistors the red yellow green and the purple blue white wires

Andrew
 
That is definitely a chassis transistor problem. I had to replace this specific one on my CT twice. If I remember I will check later and see which one it is. All I remember is that on the CT it was the easiest one to get to.

EDIT: Q606 controls the +X. It's amazing what information is available when you use the search function of this site.
 
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Thanks guys, I will be looking at all the chassis transistors tonight.....hopefully I'll get it.

Airlair, if you get the chance, please let me know which one you found to the the problem CT, as it certainly would save me a lot of time & energy.....plus reducing any risk of breaking something else...thanks!


~Patrick
 
I have the EXACT same issue... just in a different dimension. The pictures show what it looks like with two different Tempest boardsets (I know one of them has Mathbox issues).

I replaced all the 'bottlecap' transistors... I have checked them with a meter also. I am keenly interested in what fixes yours.

By the way, you mention getting your monitor boards back from Chad. Didn't you have to send your chassis frame (the part with the bottlecap transistors on it) to him along with your monitor boards?
 

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Major headway tonight. I decided to re-flow the solder connections for the chassis transistors. Upon un-mounting the 2nd one, (lower part of chassis, closest transistor to you/ back of game) I realized that one of the wires, the purple one, was poorly soldered. So I re-solder it and viola! I have a playable Tempest game~! After 2+ years....

A BIG thanks to everyone for their input!

But my saga continues, as the "game board" is bigger than the screen. That is, the game boards are "stretched" off the screen, as if it's too wide. This is for both the vertical aspect, as well as the horizontal aspect, but more so with the horizontal.

Take a look at the attached pictures....

How do I bring the size down a little? Is it something on the Main PCB board?

Thank you EVERYONE for your input and guidance thus far....

~Patrick
 

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You have adjustment pots on your main board. Put your game in test mode. Rotate the spinner till it say self test hit super zapper and fire. That will give you a white box and bunch of 0's and 1's on the screen plus a spinner test. Just spin the spinner and you'll see what I mean.
There is a tilt switch on the other side of your coin door. Activate the switch till you see the crosshatch pattern (diamonds with a square around it) use this screen to adjust height and width. Use of a mirror is helpful.
 
Hello Jimjaycee.

I know that little switch within the coin door that you're speaking about....

While in Test Mode, It's rather hard to read what it say accross the top, due the screen picture being so stretched/ oversized. I will have to try my best to read it.

What POTS am I to start adjusting on the Main PCB? I see there are 6 of them.

Thanks so much for your help!

~Patrick
 
Major headway tonight. I decided to re-flow the solder connections for the chassis transistors. Upon un-mounting the 2nd one, (lower part of chassis, closest transistor to you/ back of game) I realized that one of the wires, the purple one, was poorly soldered. So I re-solder it and viola! I have a playable Tempest game~! After 2+ years....

Awesome news. I will try that on mine too!
 
FYI - Be real gentle with the pot adjustments on tempest. The original pots are not supported well and are known for breaking off the pot.
 
Hello...

Good advice....so a little bit of a turn/ adjustment = a big picture difference?

I have had all the pots replaced with updated/ newer ones from Matt here on the forums.....

Thanks!

~Patrick
 
Alright, got the X & Y size setting right where I want them , as well as the X & Y center settings.....

Those pots are VERY sensitive indeed. A little bit makes a BIG change/ shift.

Thanks for all the guidance!


I got one last concern/ observation that I hope I can iron out....

On the right-hand side/ half of the screen all the "red objects" are exactly that--red. But on the left-hand side/ half of the screen, the "red objects" have a decent amount of orange to them. Is there a possible tweak/ protocol to smooth this out?

Once again, a BIG thanks to everyone! I hope this thread will provide some guidance for others.

~Patrick
 
your welcome

Andrew

Major headway tonight. I decided to re-flow the solder connections for the chassis transistors. Upon un-mounting the 2nd one, (lower part of chassis, closest transistor to you/ back of game) I realized that one of the wires, the purple one, was poorly soldered. So I re-solder it and viola! I have a playable Tempest game~! After 2+ years....

A BIG thanks to everyone for their input!

But my saga continues, as the "game board" is bigger than the screen. That is, the game boards are "stretched" off the screen, as if it's too wide. This is for both the vertical aspect, as well as the horizontal aspect, but more so with the horizontal.

Take a look at the attached pictures....

How do I bring the size down a little? Is it something on the Main PCB board?

Thank you EVERYONE for your input and guidance thus far....

~Patrick
 
Any thoughts on the left-side and right-side color differences?

Thanks...
 
Any thoughts on the left-side and right-side color differences?

Thanks...

Sounds like a degaussing/magnetic issue. Mine does the same thing, more or less, depending on what side of the room it's on. Spin the whole machine once and see if the colors change.
 
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