Service manual

Wells-Garnder Color Vector Monitor Guide
Page 36 of 73
ADJUSTMENT OF CONVERGENCE
In most cases, you should never have to converge, or reconverge your monitor yoke and tube.
However, if you are replacing the tube, or your deflection yoke has been knocked loose, you will
need to converge (or realign) the yoke.
You will need some rubber wedges and magnetic shunts to perform a convergence. You can
order some from your closest Mazzco dealer - http://www.mazzco.com. Give them these Wells
Gardner part numbers - (wedges) 008X0374-001 and (magnetic shunts or tabs) 009A2808-001.
They are approximately $0.40 cents each. You might also get a hot glue gun.
1. Feed crosshatch signal to the monitor [using either a pattern generator or a working
vector game board in self-test mode].
2. Insert a wedge temporarily and fix the Deflection Yoke. NOTE: The wedges may need to
be moved during adjustments.
3. Adjust the yoke back and forth until all the colors (usually separated at this point) are a
clean red, green and blue.
• Tilting the angle of the yoke up and down adjusts the crossover of both vertical and
horizontal red and blue lines (Figures 8a and 8b).
• Tilting the angle of the yoke sideways adjusts the parallel convergence of both
horizontal and vertical lines at the edges of the screen (Figures 9a and 9b).
• Make sure the crosshatch grid is straight and not warped.
4. Put a rubber wedge temporarily up top to keep the position of the deflection yoke.
5. Adjust the color purity (see below).
6. Install three permanent rubber support wedges for the deflection yoke.
7. Do NOT force the permanent wedges in. They are to be inserted until they just make
contact with the yoke - after the yoke has been positioned.
8. Fix the three permanent rubber wedges with chloroprene rubber adhesive (or equivalent).
9. After the adhesive has dried enough to hold the wedges in place, carefully remove the
temporarily installed wedge(s).
10. Use your paper magnetic shunts to properly align the beam edges. It is almost impossible
to align the edges without using the shunts.