Introduction

The WG6100 x-y color monitor was used on many of Atari's most famous video games including Tempest, Space Duel, and several others.

If your WG6100 does not work, installing a Zanen cap kit #206 can solve many problems without you knowing exactly what's wrong. For most people not familiar with this monitor, it's an excellent starting point to fix your monitor. And at $15 per kit, you can't get these parts that cheaply anywhere else.

To finalize your WG6100 repair, I would recommend installing a LV2000 low voltage board. At $30 (or $36 installed if you send them your WG6100 deflection pcb), this will also save you considerable time, trouble and money in the end. Between the Zanen kit #206, the upgrades described here, and the LV2000, you should end up with a working (!) and "bullet proof" Wells-Gardner 19K6100 X-Y color monitor. Even if your monitor is completely dead, installing these two kits and doing the upgrades should give you a working monitor (without you knowing anything about fixing monitors too!). For more info on the LV2000, see http://www.diac.com/~jeffh/lv2000.

Zanen's Standard Instructions:

This monitor repair kit is designed for the Wells-Gardner 19K6100 X-Y color monitor, as used in Tempest, Space Duel, and other Atari color X-Y games.

Be sure to install all the parts on the monitor even though many of the original parts seem to be working fine. Age, humidity, and temperature will cause the value of electrolytic capacitors to change. Also the other semi-conductors included fail often. Install them all.

Each capacitor is polarized and should only be inserted in the proper direction. Watch the polarity markings on each capacitor. On the top side of the monitor board where each capacitor is located is a circle with a plus sign next to one of the holes. The plus sign indicates where the positive (+) lead of each capacitor is to be installed.

Important: It is possible for a failure on the game logic board to cause the monitor to fail. There is a simple test to find out if the game board caused the monitor to fail. To perform the text you will need a voltmeter. Set the voltmeter on the DC voltage scale and measure the voltage on the lead 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 +.5 to -.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.

Important: It is very important to resolder all the molex connectors soldered to the monitor circuit boards. Plugging and unplugging these connectors can crack the solder joints.

End of original Zanen installation instructions

The REAL Installation/Upgrade Story

When I ordered the Zanen #206 cap kit, I felt the instructions were rather brief and disorganized. There are over 30 parts to install on three pcb's! Which ones go where? These instructions should help correct that.

Also note the Zanen cap kit #206 is based on specs for the original revision of the Wells-Gardner 19K6100 X-Y Color monitor. There have been three revisions of this monitor, to address some of its shortcomings. Although these upgrade parts are not included in the Zanen cap kit, I would highly recommend you install the upgrade parts while the monitor is apart. You'll have to buy some additional parts, which are listed at the end of this document.

Also, I would recommend installing a LV2000 low voltage board. This will also save you time and trouble in the end. And between the upgrades described here and the LV2000, you'll end up with a "bullet proof" Wells-Gardner 19K6100 X-Y color monitor. For more info on this upgrade, see http://www.diac.com/~jeffh/lv2000.

Key:
• Q = Transistor
• R = Resistor
• C = Capacitor (all polarized electrolytic)
• F = Fuse
• D = Diode
• ZD = Zener Diode

All the monitor chassis transistors are mounted in a socket with two phillips head machine screws. No soldering necessary; just unscrew the old one and replace. You can't put these in backwards; the leads are offset so these big metal transistors only fit into the chassis and screw down in one direction. If you put them in backwards, the screw holes will not line up.

Make sure you install the clear plastic Mica insulator between the transistor and the metal monitor chassis. New ones are not included in the Zanen kit! If you have some white heat shink grease, put some on both sides of the Mica insulator.

Important: after replacing the above transistors, use your DMM set to Ohms and check the continuity between the metal monitor chassis and the metal case of the above transistors. If there is continuity, you need to replace the thin clear plastic Mica insulator that goes between the transistor and the monitor chassis. There should be NO continuity! If there is continuity, you will usually blow R100 or R101 (assuming you don't have an LV2000 installed). You will probably also take out the 2N3716 or 2N3792 involved too.

The Deflection board is the main PCB mounted right behind and below the monitor tube.

All the above parts are located in the low voltage section of the Deflection board.

Important: if you are installing an LV2000 (highly recommended), you do not need to install ANY of the above parts. They will all be removed and replaced by the LV2000 installation.

The following Deflection board parts should also be replaced, and are not included in the Zanen kit, and are not replaced by the LV2000. I would recommend installing these upgraded parts. These will bring your deflection board to the last revision created by Wells-Gardner.

* Note: R812 and R813 are only used in the 2nd (P327) and 3rd (P339) revisions of the Deflection board. If you have the first revision (P314), these parts will not be present.

Although not included in the Zanen kit, you should check the Deflection board capacitors at C100 and C101 (both are 4700 mfd, 50v). Also test the 5A2 (1N4005 or NTE116) rectifier diodes at D100, D101, D102, D103. These rectifiers are 600v, 1 amp components. You can upgrade them to 5A8 (1N4007 or NTE125) diodes that spec at 1000v, 2.5 amps.

To test capacitors you'll need a DMM that does this. Most don't, and the ones that do often won't go to 4700 mfd. If in doubt, just replace them.

To test diodes, you must remove one lead of the diode from the board. Then put your DMM on the diode setting. Put your test leads on the diode and note reading. Reverse the leads and test again. In one direction you should get a null reading (no activity on the meter). In the other direction you should get betweeen .4 and .8 volts. If in doubt, replace the diode. They are cheap!

Note the new 1N4007 diodes used at locations D100 to D103 will be considerably smaller than the 15 year old original diodes. Don't worry about this; new products are smaller, yet more durable.

The High Voltage PCB (in the metal cage next to the flyback transformer) had several revisions too. I would recommend doing the "upgrade" parts here too. This brings your HV pcb to the lastest revision.

HV Board Notes.
On the HV circuit board there are two diodes which the Atari TM-183 manual does not identify. They are just referred to as "silicon diodes". Apparently the replacement for these is NTE558. Also be careful installing the zener diode ZD902. Apparently some people mistakenly install this at D902 instead of ZD902. The monitor will not work if you make this mistake!

The Neck Board is the PCB attached to the neck of the monitor tube.

* these parts may be optional for your monitor.

Testing Your Work.

Test the Boardset Outputs before Turning the Monitor On.
Make sure the game board is outputing correct voltages before you power the monitor on! Otherwise you can waste the monitor and all the above work. To test these set your DMM 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 +.5 to -.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 chassis-mounted large transistors (2N3716 and 2N3792). Set your DMM 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 don't, there's a good chance one of those chassis-mounted transistors is bad. With the monitor off, use your DMM (set to continuity ohms) and make sure the metal monitor chassis is not shorted to the metal case of each of the chassis mounted transistors. If it is, the mica insulator is probably damaged (and the transistor is probably blown).

Screen Gitters After the Game Warms Up.
The small XY adjustment trim pots on the Tempest game boardset are probably at fault. These trim pots are factory adjusted and sealed with some hot-melt glue. As the board warms up, the expansion rate of the trim pots and the hot-melt glue is different. The glue can expand enough to separate and damage the small plastic pots! You can try removing the glue, but often you will have to replace the small trim pots (10k, 2k, 200 ohms). The only hard value to find is the 200 ohm pot (the 10k trim pots you can get at Radio Shack). You can get the 2k and 200 ohm trim pots from Mouser.

Additional Information.
Here's some additional links for info on X-Y monitors.

• X-Y Monitor Page
• Monitor manual, PDF format (tempest_monitor_tm183.pdf)
• Testing the WG6100 High Voltage Transformer
• WG6100 Schematics, part one
• WG6100 Schematics, part two
• XY Greg Woodcock's Monitor Repair document *

* Thanks to Greg Woodcock for his great (and long!) XY repair document. The upgrades mentioned above are summarized from his document.