Wells-Gardner Vector Monitor 6100 Faq And Guide Version

							Wells-Garnder Color Vector Monitor Guide Page 51 of 75 IMPROVING YOUR WELLS-GARDNER 6100 MONITOR  
 
Now that you have your monitor repaired and adjusted, we will discuss the variety of ways that 
exist to make your monitor (or rather, your deflection board) more robust and hopefully reduce 
or eliminate future failures. 
  
OFFICIAL ATARI DEFLECTION BOARD UPGRADE 
 
Here is some text from the Major Havoc conversion kit installation instructions (TM-268). It 
describes the Atari sanctioned upgrades and includes instructions for converting all Wells-
Gardner P314 Deflection Board PCB variations to Ataris official upgrade. Thanks to Tony 
Jones for the transcription. 
 
 
Major Havoc Installation Instructions TM-268 
 
MODIFY THE WELLS-GARDNER DEFLECTION PCB 
 
NOTE: The following procedure applies to those Space Duel, Gravitar, and Black Widow 
games that used a Wells-Gardner display. 
 
Four versions of the Wells-Gardner display were used in the Tempest, Space Duel, Gravitar, and 
Black Widow games. Perform the preliminary procedure for all versions of the display, and then 
refer to Table 3 to determine which version of the four displays was installed in your game and 
perform the additional procedure for that version. CAUTION! When soldering components to 
the display circuitry, apply just enough heat to provide a proper electrical connection. Excessive 
heat can damage the semiconductor material. 
 
Preliminary Procedure 
 
Perform the following procedure to modify the Deflection PCB (see Figure 6). 
 
1. Set the display on a clean work surface.  
2. Disconnect the 15-pin Molex connector from the mounting bracket on the display chassis 
and the harness connectors from the Deflection PCB and the Neck PCB.  
3. Use a 1/4-inch hex driver to remove the two screws securing the Deflection PCB to the 
display chassis [NOTE: there are holes for two more screws in the remaining (rear) two 
corners of the board which some users decided to fill; if the board will not come out, 
check for this]  
4. Remove the Deflection PCB from the display.  
5. Connect two type-1N754A Zener diodes together, anode to anode, as shown in Figure 6. 
Use a soldering iron to solder the two anode leads together.   
						

							Wells-Garnder Color Vector Monitor Guide Page 52 of 75  
Figure 6 - IN754A and 1N756A Zener-Diode Connections 
 
                          Solder Here 
                              | 
        CATHODE +-+------+   \|/   +------+-+ CATHODE 
        --------+ |1N75#A+---------+1N75#A| +-------- 
                +-+------+ ANODES  +------+-+ 
 
                ----||---- 
 
 
6. Connect two type-1N756A Zener diodes together and solder as described in step 5.  
7. Examine the soldered side of the Deflection PCB removed from the display and 
determine which of the two PCBs matches your PCB. [either a P314 or a P327/339] 
8. On the component side of the Deflection PCB, locate the yellow wire (top right side of 
the PCB).  
9. Solder one cathode lead of the two type-1N754A Zener diodes (soldered together in step 
5) to the yellow lead on the soldered side of the PCB as shown in the appropriate 
illustration in Figure 7.  
10. Solder the other cathode lead of the two type-1N754A Zener diodes to ground as shown 
on the appropriate illustration in Figure 7.  
11. On the component side of the Deflection PCB, locate the orange wire (near top center of 
the PCB).  
12. Solder one cathode lead of the two type-1N756A Zener diodes (soldered together in step 
6) to the orange lead on the soldered side of the PCB as shown on the appropriate 
illustration in Figure 7.  
13. Solder the other cathode lead of the two type-1N756A Zener diodes to ground as shown 
on the appropriate illustration in Figure 7.  
14. On the component side of the Deflection PCB, locate connector P600 (right center of the 
PCB).  
15. Solder the cathode lead of a type-1N4002 diode to pin 1 and the anode lead to pin 4 of 
connector P600 on the soldered side of the PCB as shown on the appropriate illustration 
in Figure 7.  
16. Solder the cathode lead of a type-1N4002 diode to pin 5 and the anode lead to pin 7 of 
connector P600 on the soldered side of the PCB as shown on the appropriate illustration 
in Figure 7.  
17. On the component side of the Deflection PCB, locate connector P700 (left center of the 
PCB).  
18. Solder the cathode lead of a type-1N4002 diode to pin 1 and the anode lead to pin 4 of 
connector P700 on the soldered side of the PCB as shown on the appropriate illustration 
in Figure 7.  
19. Solder the cathode lead of a type-1N4002 diode to pin 5 and the anode lead to pin 7 of 
connector P700 on the soldered side of the PCB as shown on the appropriate illustration 
in Figure 7.  
20. Refer to Table 3 to determine which of the four versions of the display has been installed 
in your Tempest game.  
						

							Wells-Garnder Color Vector Monitor Guide Page 53 of 75  
Table 3 - Display Versions 
 
Version 1 
Deflection PCB has two large, black, tubular capacitors, C804 and C805, 
installed below top center of PCB. Version 2 
Input Protection Circuit PCB is installed (piggyback) WITH A 1K Ohm, 
+/-5%, 1/4 W RESISTOR CONNECTED BETWEEN THE INPUT 
PROTECTION CIRCUIT PCB AND THE DEFLECTION PCB. Version 3 
Input Protection Circuit PCB is installed (piggyback) BUT DOES NOT 
HAVE A RESISTOR CONNECTED BETWEEN THE INPUT 
PROTECTION CIRCUIT PCB AND THE DEFLECTION PCB. Version 4 
Deflection PCB DOES NOT HAVE CAPACITORS C804 AND C805 
(BELOW TOP CENTER OF PCB) OR AN INPUT PROTECTION 
CIRCUIT PCB INSTALLED.  
 
 
21. Perform the procedure as follows for the appropriate version of the display determined 
from Table 3. (Refer to the display manual, TM-183, for component and connector 
locations). 
 
NOTE: The 30K ohm, 1/4W resistor supplied in the kit is used only for Version 1 of the Wells-
Gardner display. 
  
Version 1 Deflection Board 
 
Perform the following procedure for Version 1 of the Wells-Gardner 6100 display. 
 
1. Verify that the Preliminary Procedure has been performed. [see above] 
2. Use a soldering iron to remove resistor R811 and replace it with the 30K ohm, 1/4W 
resistor supplied in the kit. 
3. Use a 1/4-inch hex driver to secure the modified Deflection PCB to the display chassis.  
CAUTION!: Make certain that the harness from Q705 and Q706 is connected to P700 
and not P100. 
4. Connect the harnesses to the appropriate Deflection PCB connectors. 
  
						

							Wells-Garnder Color Vector Monitor Guide Page 54 of 75  
Version 2 Deflection Board 
 
Perform the following procedure for Version 2 of the Wells-Gardner 6100 display. 
 
1. Verify that the Preliminary Procedure has been performed. [see above] 
2. Use a 1/4-inch hex driver to secure the modified Deflection PCB to the display chassis. 
CAUTION!: Make certain that the harness from Q705 and Q706 is connected to P700 
and not P100. 
3. Connect the harnesses to the appropriate Deflection PCB connectors. 
  
Version 3 Deflection Board 
 
Perform the following procedure for Version 3 of the Wells-Gardner 6100 display. 
 
1. Verify that the Preliminary Procedure has been performed. [see above] 
2. Locate the wire connected to resistor R1 (22K ohm) and the collectors of transistors Q1 
and Q3 (type 2N3904) on the Input Protection Circuit PCB and the point shown in Figure 
7 on the Deflection PCB. 
3. Use a wire cutter to cut the wire, located in step 2, halfway between the two PCBs.  
4. Use a soldering iron to solder a 1K-Ohm, +/-5%, 1/4 W resistor (not included in the kit) 
between the two ends of the wire cut in step 3. 
5. Use a 1/4-inch hex driver to secure the modified Deflection PCB to the display chassis. 
CAUTION!: Make certain that the harness from Q705 and Q706 is connected to P700 
and not P100. 
6. Connect the harnesses to the appropriate Deflection PCB connectors. 
  
Version 4 Deflection Board 
 
Perform the following procedure for Version 4 of the Wells-Gardner 6100 display. NOTE: This 
version of the display requires that an Input Protection Circuit PCB assembly be installed on the 
Deflection PCB as part of the display modification procedure. This PCB assembly is not 
included in the kit. However, to obtain the Input Protection Circuit PCB assembly, use the order 
form at the back of this document. 
 
1. Verify that the Preliminary Procedure has been performed. [see above] 
2. Install the Input Protection Circuit PCB to the Deflection PCB as described in the 
instructions supplied with the Input Protection Circuit PCB assembly. 
3. Use a 1/4-inch hex driver to secure the modified Deflection PCB to the display chassis.  
CAUTION! Make certain that the harness from Q705 and Q706 is connected to P700 
and not P100. 
4. Connect the harnesses to the appropriate Deflection PCB connectors. 
 
  
						

							Wells-Garnder Color Vector Monitor Guide Page 55 of 75 THE INPUT PROTECTION CIRCUIT (IPC)  
 
This Modification is for P314 versions of the Deflection Board ONLY. The P327 and P339 
versions already have this circuit designed into the board. Here is the text from Atari CO-183-02 
(1st printing) that describes a circuit that was sold by Atari to help make the deflection board 
more robust. This input protection circuit is unavailable but very simple and easy to recreate 
from the schematics provided herein. 
  
New Input Protection Circuit For Wells-Gardner Color X-Y Display 
(Supplement to TM-183) 
 
This display contains an additional small printed-circuit board (PCB) that is not described in the 
display manual (TM-183). The PCB is mounted in piggy-back style on top of the Deflection 
PCB. 
 
The input protection board was added to protect the fuses in the display from damaging input 
voltage conditions. Without this board, the display fuses might blow in the event of an 
intermittent or long-term game PCB failure. With this board, the screen will momentarily go 
blank if the average X- or Y-axis voltage(s) exceed a certain level. The screen then automatically 
recovers for normal game play and earning when the voltage(s) return to normal. 
 
If this display is used in a Tempest (TM) game, be sure to correctly adjust the X and Y SIZE and 
CTR video pots on the Tempest Analog Vector-Generator (main) PCB [see text above]. The 
instructions for these adjustments are printed on the Tempest schematics - Sheet 2, Side B - 3rd 
printing or later. Improper adjustment may cause the screen to go blank during normal game 
play. 
  
 
Input Protection Circuit (IPC) PCB Parts List Part No. Description (Reference Designations in parentheses) 24-250107 100 uf Aluminum Elec. Fixed Axial-Lead 25V Capacitor (C1,2) 31-1N914 75V Type-1N914 Switching Diode (CR2-4) 32-1N751A 5.1V 400mW Type-1N751A Zener Diode (CR1) 33-2N3906 PCB Switching and Amplifying Transistor (Q2, 4, 5) 34-2N3904 Type-2N3904 NPN 60V 1-Watt Transistor (Q1, 3) 52-222 22-Gauge Jumper Wire (2 in. required) 110000-223 22K Ohm, +/- 5% 1/4 W Resistor (R1, 8, 11) 110000-273 27K Ohm, +/- 5% 1/4 W Resistor (R5) 110000-393 39K Ohm, +/- 5% 1/4 W Resistor (R4) 110000-682 6.8K Ohm, +/- 5% 1/4 W Resistor (R6, 7)  
						

							Wells-Garnder Color Vector Monitor Guide Page 56 of 75 110001-222 2.2K Ohm, +/- 5% 1/2 W Resistor (R10) 110001-472 4.7K Ohm, +/- 5% 1/2 W Resistor (R9) 110011-122 1.2K Ohm, +/- 1% 1/4 W Metal-Film Resistor (R2, 3) 110000-102 1K Ohm, +/- 5% 1/4 W Resistor (R12) A038088-01 B INPUT PROTECTION CIRCUIT PCB ASSEMBLY  
  
Schematic of the Input Protection Circuit PCB 
  
  
						

							Wells-Garnder Color Vector Monitor Guide Page 57 of 75 COLOR X-Y DISPLAY 92-053 
INSTALLATION INSTRUCTIONS 
INPUT PROTECTION CIRCUIT PCB 
 
A038088-01 
 
 
1. Remove R600, R605, R700 and R706. 
2. Remove solder from all nine holes indicated in figure 13 [figure not included].  
3. Straighten pins of PCB so that they are perpendicular to the board [meaningless to you 
since you probably do not have the board].  
4. Match and insert the numbered holes in figure 13 with the numbered pins in figure 1 
[figures not included].  
5. Solder. 
 
All descriptions refer to a deflection board oriented component side up with the board label 
P314 at the top (right-side-up) and the two large electrolytic capacitors at the bottom. This 
orientation will have the electrolytic capacitors side by side and the board will be taller than 
it is wide. 
 
· J1 is R700s old top pin.  
· J2 is R700s old bottom pin.  
· J3 is R600s old top pin.  
· J4 is R600s old bottom pin.  
· J5 is the first empty/unused hole to the right of C701.  
· J6 is the first empty/unused hole to the right of Q701 and below C701.  
· J7 is the first empty/unused hole to the left of C602 and below D601.  
· J8 is R606s old left pin.  
· J9 is R706s old left pin.  
 
SPECIAL NOTE: According to the Major Havoc manual, this Input Protection board came in 2 
versions. Later versions had a 1K-Ohm, +/-5%, 1/4 W resistor as one of the stilts on the board 
instead of a plain piece of wire. If your board does not have this resistor, here is what you need to 
do. 
 
· Locate the stilt wire connected to resistor R1 (22K ohm) and the collectors of 
transistors Q1 and Q3 (type 2N3904) on the Input Protection Circuit PCB (the other end 
is connected to the P314 Deflection PCB). 
· Use a wire cutter to cut the wire, located in step 1, halfway between the two PCBs.  
· Use a soldering iron to solder a 1K-Ohm, +/-5%, 1/4 W resistor between the two ends of 
the wire cut in step 2. 
 
  
						

							Wells-Garnder Color Vector Monitor Guide Page 58 of 75 INPUT PROTECTION CIRCUIT PCB (continued) 
 
 
  
 
 
  
						

							Wells-Garnder Color Vector Monitor Guide Page 59 of 75 Appendix A:  X-Y Monitor/Final Solution (sort of)  
 
WELLS GARDNER 
X-Y MONITOR/FINAL SOLUTION 
By Wayne McGuire, Brady Dist, Charlotte, NC 
[edited for content by Tom McClintock; additional notes by Zonn Moore] 
 
 
 
STANDARD DISCLAIMER: 
-------------------- 
REMEMBER, NO WARRANTEES, EXPRESS OR IMPLIED, ARE GIVEN.  USE THIS 
INFORMATION AT YOUR OWN RISK. I AM NOT RESPONSIBLE FOR ANY 
DAMAGES THAT MAY OCCUR TO YOUR PERSON OR PROPERTY. 
 
 
------------------------------ 
Source: 
Star*Tech Journal  
December 1983 
Volume 5, Number 10 
Pages 14 and 15 
------------------------------- 
 
We at Brady Distributing Co. pride ourselves on the service we have been able to offer our 
customers. The following modifications are a product of our shop personnel and, in our 
estimation, a final solution to the Wells Gardner X-Y monitor problems. 
 
Over the past three months, we have modified every Well Gardner X-Y monitor to cross our 
bench and the rate of repeated failure is such that only one has returned with a deflection 
problem. These changes make the 19K6901 and 19K6103 very reliable monitors and much better 
suited for the environments in which they are operated. 
 
BRADY MODIFICATIONS FOR WELLS GARDNER QUADRASCAN COLOR X-Y 
 
1 - INPUT PROTECTION CIRCUIT PCB ASSEMBLY 
 
To ensure continued circuit operation, Atari Field Service suggests that you perform the 
following modification: 
 
A. Remove the lead connecting the IPC board to +27 volts on the display printed circuit 
board. The lead is near Q1 and Q3 (see Fig 1.1). 
 
 B. Replace this lead with a 1K ohm, 1/4-watt resistor (see Schematic of  Fig 1.1). 
  
						

							Wells-Garnder Color Vector Monitor Guide Page 60 of 75 2 - POWER SUPPLY CIRCUIT 
 
The Low Voltage Power Supply is to be bypassed in this modification. The input stages of the 
deflection circuits used in this monitor are of the differential type and exhibit a high common 
mode rejection. This characteristic will filter out any noise or ripple of the power supply. 
 
A. Cut diodes D104 and D105 out of the power supply circuit (Schematic 2.1) 
 
 B. Cut the wires at P100 leaving about two inches at the plug. 
 
C. Make a Rat Tail splice connecting the leads at pins 1 and 4; also, splice the leads at 
pins 5 and 7. [Note that pin 2 is missing from the plug.] 
 
D. Solder and cover the exposed wire with electrical tape or shrink tubing. 
 
 E. Cut the remaining wires flush with the plug (leads at pins 3 and 6). 
 
[Alternatively, you could make a non-destructive modification by using a 7-position molex (or 
comparable) plug and making a wire loop between pins 1 and 4, and 5 and 7. Never a very good 
idea to cut up your original harness! An interesting benefit of this modification is that it removes 
two chassis transistors (Q102 and Q103) from the monitor. Please refer to Schematic 2.1] 
 
NOTE: This [Low Voltage Power Supply] modification will require readjustment of the monitor 
color, focus and signal level from the logic board. This is due to the higher supply voltage now 
available at the deflection and color stages. This modification will remove about 45 watts of 
power from the bottom plate of the monitor chassis and cause a noticeable reduction in 
temperature. 
 
[notes from Zonn: 
* Though it claims otherwise, removing the regulator from the low voltage side make for 
irritating jitters and blooming on the vectors.  This might not be so bad from an 
operators point of view, but as a collector is was unacceptable. 
 
* Removing the regulator increases the voltage across the output yoke drivers. This might 
have an advantage of a slight increase of vector speeds when moving large distances, 
but it also means the transistors must dissipate more heat during large movements. 
Since Tempest was written for the monitor as it was designed, the speed increase is 
meaningless, but the heat dissipation is critical! 
 
* The low voltage regulator designed by Atari really sucked, I came up with a re-design 
that was slightly more complicated than the LV2000 -- I switched to the LV2000.  The 
best thing to do with the low voltage section is to install an LV2000.]