Tempest playing blind

S4Patrick

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The sound & game play is 100% working, just no monitor/ picture.

Things I've observed:

-Monitor neck has the orange glow
-All fuses at power supply except at F6 check OK
-Both LEDs on the LV2000 light up
-Spot killer LED doesn't light up at all--even when 1st powering up the Tempest
(this LED should at least -flash/ flicker for a sec or two upon start-up, right?)
-F100 fuse location voltage reading: 25.00 volts
-F101 fuse location voltage reading: 25.00 volts
-No voltage readings at F600 & F700 fuse positions
-Voltage readings on the two black wires within the main wire harness for monitor are 25.20 volts
-Game will go into Test Mode, but still no picture/ video
-LED on both the main PCB & AUX boards are on


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I swapped out the two transistors that are off the wire harness right near the LV2000 location and powered on the Tempest, to no avail. Still same the exact same state--playing blind.

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Using a DMM, I get no voltage output/ reading on either side of the fuse holder at the F6 fuse location on the power supply.
-Could someone tell me what the F6 fuse position powers/ does and what would cause it to have no voltage output?

There's also no voltage readings at F600 & F700 fuse positions on the deflection board. What would not allow for no voltage there and if there was, what voltage reading am I looking for?

I also noticed that there's no LED on the HV cage/ PCB. Is this something that Atari added to the design later on as a running change/ update?

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Updates/ fixes I've done over the last 2 years (or less)
*ArcadeCup work done to all 3 monitor boards (with LV2000 installed)
*New "big Cap" on power supply (Bob Roberts)
*Main PCB, Aux PCB, and power regulator PCB boards sent for repair work to two reputable repair facilities. (Electron Forge & (also tested on another Tempest game and the boards all work 100%)
*Replaced full wire harness
*Monitor transistors replaced (all 6)
*Reseated all wire harness and wires within the connectors several times

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Any ideas/ suggestions?

Thanks everyone....
 
Did you say that you have deflection "chatter"? Your correct, you should have the spot killer at least come on for a second or two while the game boots.

1. Two leds on the LV2000 indicate that the monitor is getting power.
2. Spot killer not coming on leads me to believe that either theres still a power supply issue, or the spot killer isnt working.

Unplug everything from the deflection board except the input and the connector closest to the LV2000 (P100). If everything is working properly the spot killer should be on, and you should have +- 27 volts on pins 4 and 5 of P100. If thats good, then the power supply is fine, and you can move on.
 
I'm 100% sure there's no deflection chatter at all. that LED doesn't even flicker and there's zero noise/ chatter.

So when disconnecting everything from the deflection board, that includes all harnesses, including the HV cage one, the 2-wire monitor degaussing one, as well as all others except the P100 and the main input harness?

The main input harness it that fat harness "brick" that is mounted to the monitor chassis, right? It has a section of wires that splits down to the game PCB....

Also, if you can tell me, what colors are pins 4 and 5 of P100 connector?

Any idea on what the F6 power supply fuse position powers?

Thanks...
 
Dont get hung up on F6..Google the manual and see if you can find it in there. If the game is playing blind, and your getting leds on the lv2000, your way past a power brick issue. Your problem is either on the deflection board or frame.

Yes, unplug everything else. Youve got to establish that the power supply is working first. I dont know what the colors are, but I think they are the middle two pins. You can also try all 6, you should get (starting at pin 1) +34, (key),+28,+27, -27,-28,-34.
 
Thank you for your suggestion...

As you suggested, I unplugged everything from the deflection board except for the main harness input (large harness for deflection board/ monitor) and the connector closest to the LV2000 (P100)

Here are the voltages I measured at P100:

Pin 1 (red) + 33.10
Pin 2 (blank) -----
Pin 3 (green) +27.70
Pin 4 (yellow) -1.50
Pin 5 (white) -27.10
Pin 6 (blue) -27.70
Pin 7 (purple) -33.30


Pin 4 is clearly way off. Ideas?

Thanks this far....
 
Last edited:
Good news, I got the Tempest up & running.

It was indeed a bad 2n3716 transistor that was off the wire harness near the LV2000.

I did replace that transistor during my 1st attempts of fixing the blind issue, but the replacement 2n3716 I put in had to have been defective. Into the garbage can that transistor went.

A BIG THANKS to both mcandrewsoun & Slackmoe for your input/ and suggestions.

And you're right ieure, those solder joints are very failure-prone. Checking those wire connections is something that definitely needs to be inspected immediately when the monitor goes blind.

Thanks again everyone....
 
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