WG 6100 - spot killer

[duncanator]

I've reached the limit of my knowledge of how to fix this thing and was hoping someone might know what I can do to fix the WG6100 monitor in my Atari Tempest. The following is a summary of what is happening and what I have done.

The current and initial problem is that the game plays blind with the monitor spot killer light on and no charge in the monitor. With my HV Probe, there is nothing to discharge.  After much reading, watching John's videos, and using the deluxe cap kits (plus additional parts) from Bob Roberts, I replaced darn near everything I can think of. I have replaced everything from the cap kit, all the chassis transistors (check for shorting to the chassis), and installed the LV2000 (working). I have not replaced the flyback transformer, but am not sure how to test that.
I have not tested the output from the main board because I am not sure how to test that. Is there any advice anyone can offer? Thank you.

[John's Arcade]

Did you read the 6100 FAQ? It's amazing.

http://www.ionpool.net/arcade/tech/6100_faq.pdf

I am not sure what to tell you but the first thing I thought of was "Is it a board problem?". If the monitor is getting no video signals that spot killer will come on. The FAQ talks about checking your video signal output voltages.

http://www.skepticfiles.org/cowtext/arcade/atarixyh.htm

"The spot killer also lights if the logic board does not supply the low level X and Y signals for the monitor to
amplify."

[duncanator]

Did you read the 6100 FAQ? It's amazing.

http://www.ionpool.net/arcade/tech/6100_faq.pdf

I am not sure what to tell you but the first thing I thought of was "Is it a board problem?". If the monitor is getting no video signals that spot killer will come on. The FAQ talks about checking your video signal output voltages.

http://www.skepticfiles.org/cowtext/arcade/atarixyh.htm

"The spot killer also lights if the logic board does not supply the low level X and Y signals for the monitor to
amplify."

Oh, you bet I read that and I still find helpful information even after reading it a couple of times. I have attempted to check the signal output voltages, but I think I might not be doing it correctly. I think part of the reason is I don't think I know the correct number of each pin. I think I will have to label the wires so I won't forget what I am looking at. I recall reading that section, but don't recall what to check if I am not getting the correct voltage. I believe I have checked everything related to that, but I will look again. I have not had any fuse issues either so when I look at everything, it seems that it should be working.

I have taken some time off away from it for the past few weeks because I got so fed up with it so perhaps a fresh look at things will help.

[John's Arcade]

How about this?

Test the Game Board Outputs before Turning the Monitor On.
Make sure the game board is outputting correct voltages before you power the monitor
on! Otherwise you can waste the monitor and all the above work. To test the outputs, set
your meter on DC volts and measure the leads of R600 and R700 (fuses) of the deflection
board. These are connected to the plug with wire colors yellow (R600) and orange
(R700). The correct voltage should be in the +0.5 to -0.5 volt range (basically zero volts).
The voltage will fluctuate because of changing deflection signals. If the measured voltage
is between 5 and 15 volts (positive or negative), then check the X and Y amplifiers on the
GAME board. Also check for broken potentiometers on the game board.
Spot Killer On.
If the "spot killer" LED lights on the monitor's deflection board, this indicates there is a
problem. First test the voltages going to the large chassis-mounted transistors (2N3716
and 2N3792). Set your meter on DC volts. With the monitor powered on, put the black
lead on ground (the metal monitor chassis), and put the red lead on the metal case of each
of the chassis-mounted transistors. You should get either +30 or -30 volts DC. If you do
not, there's a good chance one of those chassis-mounted transistors is bad. With the
monitor off, use your meter (set to continuity ohms) and make sure the metal monitor
chassis is not shorted to the metal case of each chassis mounted transistor. If it is, the
mica insulator is probably damaged (and the transistor is probably blown)

[iankellogg]

the spot killer doesn't affect the HV. so it sounds like something is wrong there if there is no HV when you probe.

I dont know what knowledge you have for debugging power supplies but the short of it is you need to make sure you have your -26V, +26V and B+ going to the HV board. Then check that the 555 timer is running properly. If your meter has a frequency check or use a scope on pin 3 to make sure you are running, should be somewhere around 20khz. If that is still working it might be worth considering that the HV diode is dead. This is almost impossible to test, if you are lucky its shorted and you know its bad. but they can be open and there is no way to find out. the forward drop of that thing is around 180V so no multimeter diode test will cut it.

[duncanator]

Thanks so much for the advice. I will be sure to check everything mentioned this week and hopefully get it running again. I was very careful in replacing everything and the machine is in such good shape that I'd hate to have it sitting idle any more than it has to. I think this game was rarely played because it is original and looks like it never saw the inside of an arcade.

Again, many thanks for the advice.

[John's Arcade]

the spot killer doesn't affect the HV. so it sounds like something is wrong there if there is no HV when you probe.

I dont know what knowledge you have for debugging power supplies but the short of it is you need to make sure you have your -26V, +26V and B+ going to the HV board. Then check that the 555 timer is running properly. If your meter has a frequency check or use a scope on pin 3 to make sure you are running, should be somewhere around 20khz. If that is still working it might be worth considering that the HV diode is dead. This is almost impossible to test, if you are lucky its shorted and you know its bad. but they can be open and there is no way to find out. the forward drop of that thing is around 180V so no multimeter diode test will cut it.

He didn't say he has no HV.

He said the monitor doesn't discharge. I am pretty sure the 6100 is a self discharging monitor. We all discharge it anyways to be safe. No SNAP when discharging is OK.

[duncanator]

the spot killer doesn't affect the HV. so it sounds like something is wrong there if there is no HV when you probe.

I dont know what knowledge you have for debugging power supplies but the short of it is you need to make sure you have your -26V, +26V and B+ going to the HV board. Then check that the 555 timer is running properly. If your meter has a frequency check or use a scope on pin 3 to make sure you are running, should be somewhere around 20khz. If that is still working it might be worth considering that the HV diode is dead. This is almost impossible to test, if you are lucky its shorted and you know its bad. but they can be open and there is no way to find out. the forward drop of that thing is around 180V so no multimeter diode test will cut it.

After thinking about your comment for a bit, I did test the B+ and it checked ok. I do think I have a problem with the other test to the HV board (-26V, +26V) so I will research how to test that properly.  Thanks.

[duncanator]

Re: "Test the Game Board Outputs before Turning the Monitor On.
Make sure the game board is outputting correct voltages before you power the monitor
on! Otherwise you can waste the monitor and all the above work. To test the outputs, set
your meter on DC volts and measure the leads of R600 and R700 (fuses) of the deflection
board. These are connected to the plug with wire colors yellow (R600) and orange
(R700). The correct voltage should be in the +0.5 to -0.5 volt range (basically zero volts).
The voltage will fluctuate because of changing deflection signals. If the measured voltage
is between 5 and 15 volts (positive or negative), then check the X and Y amplifiers on the
GAME board. Also check for broken potentiometers on the game board."

I was reading this part and wanted to make sure I understood. The R600 and R700 on the deflection are resistors, right? Also, I poser on the game, right? I ask because the comment was to test the output before turning the monitor on so is the game plugged in and game on, but disconnected from the monitor? I have been trying to test the x and y amplifiers but don't quite understand how to do it.  Thanks!