Wells-Gardner Vector Monitor 6100 Faq And Guide Version

Wells-Garnder Color Vector Monitor Guide Page 31 of 75 CAUTION: When replacing the transistors mounted on the chassis, make sure the pins do not 
short to the chassis. If the chart procedures do not solve your problem, call Atari Field Service. 
 
 
We will finish off with a troubleshooting guide broken down by symptoms. Much of the rest of 
this section is a transcription of repair notes from a Wells-Gardner technician. Just because 
your symptom matches something in here is no guarantee that what he...

Wells-Garnder Color Vector Monitor Guide Page 32 of 75  
Symptom: Spot Killer ON and display dead 
 
Check the fuses first. If they are OK, then check the six transistors mounted on the chassis as 
described earlier. If you find at least two of the deflection transistors or one of the power 
transistors bad, then that is definitely tripping the spot killer. A good trick to figure out where the 
problem exists is to turn your brightness up all the way and see what your picture looks like. The 
spot killer...

Wells-Garnder Color Vector Monitor Guide Page 33 of 75 temperature (and the resistors heat) caused the resistor lead to separate in the hole on the board, 
while it still looked and tested fine. 
 
NOTE:  
Jeff Young from World Wide Distributors in Grand Rapids, MI reported some words of 
caution about these resistors on Page 3 of the November 1982 issue of the Star*Tech 
Journal: 
 
After fighting a problem in the Atari Tempest for three days and finding a silly 
mistake, I thought I should write to...

Wells-Garnder Color Vector Monitor Guide Page 34 of 75  
Symptom: Display bad only in lower right quadrant 
 
Distorted image, which exists ONLY in the lower right quadrant of the display. 
 
I have seen this several times and the problem has always been a bad ZD101. Much of the time 
this causes R101/Q101 to fry and spot killer comes on.  

Wells-Garnder Color Vector Monitor Guide Page 35 of 75  
NECK (CRT) BOARD PROBLEMS   
Symptom: Colors Drop In and Out (ZD500 open on neck board) or Display is too bright 
 
On neck board:  
· R515 (broken wire to R531)  
· C503 (reversed; may toast R527) 
  
Symptom: No Red 
 
On neck board:  
· R500 (open)  
· R502 (shorted to nearby component)  
· R510 (open)  
· R511 (open or wrong value)  
· R520 (open; red color can be seen but is very weak)  
· R529 (open or wrong value)  
· broken wire at R517...

Wells-Garnder Color Vector Monitor Guide Page 36 of 75  
Symptom: No Green 
 
On neck board:  
· R503 (open)  
· R513 (wrong value)  
· R520 (wrong value; was 22)  
· R530 (open)  
· Q501 (bad or base shorted to emitter)  
· broken wire at R513  
· jumper from R511 to R513 missing 
 
On deflection board:  
· neck board connector wrong type  
· broken green wire from deflection board to neck board 
  
Symptom: Only Green 
 
On neck board:  
· Q503 (reversed or wired wrong) 
  
Symptom: Green Too Bright...

Wells-Garnder Color Vector Monitor Guide Page 37 of 75  
Symptom: Green Does Not Turn Off When Dimmed All The Way 
 
On neck board:  
· R512 (shorted to nearby wire or connecting wires wrong)  
· R519 (connecting wires wrong)  
· R520 (open)  
· Q501 (reversed, open, shorted, or broken wire to base) 
  
Symptom: No Blue 
 
On neck board:  
· R504 (wrong value)  
· R515 (open or wrong value or broken wire or swapped with R505) 
 
On deflection board:  
· D803 (bad) or neck board connector wired wrong)...

Wells-Garnder Color Vector Monitor Guide Page 38 of 75  
HIGH VOLTAGE BOARD PROBLEMS   
Symptom: Display Unstable 
 
The image is extremely shaky and unstable and lines that should be straight have periodic 
wiggles along their length that make them look like an EKG (the distortion is sort of like when 
you watch TV with a bad antennae and lines walk around on the screen). 
 
Replace C901, C902, and/or C905 in the HV supply. If one of these is bad then the rest of the 
electrolytic capacitors are...

Wells-Garnder Color Vector Monitor Guide Page 39 of 75  
Symptom: Top of Q901 Blowing Off 
 
· R902 (open)  
· Q900 (inserted or wired wrong; if emitter shorted to base then Q901, Q902, and ZD901 
get fried)  
· Q901 (shorted)  
· Q902 (shorted)  
· ZD901 (shorted) 
  
Symptom: Top of Q902 Blowing Off 
 
· Q901 (reversed) 
  
Symptom: R901 and R907 are Smoking 
 
· Q902 (shorted)  
· Q906 (red and white leads interchanged) 
  
Symptom: Only R901 Smokes 
 
· Q906 (inserted wrong)  
· Q900 (missing spacer...

Wells-Garnder Color Vector Monitor Guide Page 40 of 75  
Symptom: R908 Smokes 
 
· Q900 (white and black leads interchanged) 
  
Symptom: R912 Smokes 
 
· C910 (reversed)  
· D901 (wrong value; perhaps ZD902) 
  
Symptom: R917 Smokes 
 
· Q905 (reversed) 
 
If R920 smokes, check: 
 
· C913 (bad; this can damage T901, too) 
  
Symptom: No HV (Very Dead Sound) 
 
No High Voltage (HV); you do not hear the crackling sound when you first turn the monitor on. 
 
Check the transistors in the HV unit as...