Removing The Crt - Elo TouchSystems IntelliTouch Ultra Product Manual

Removing the CRT

Removing the CRT
frame. As you pull the chassis away from the bezel, make sure that cables and frame. As you pull the chassis away from the bezel, make sure that cables and
circuit boards do not hit the neck of the CRT and that nothing becomes caught on circuit boards do not hit the neck of the CRT and that nothing becomes caught on
the adjustment rings or other components on the neck of the CRT. Also watch for the adjustment rings or other components on the neck of the CRT. Also watch for
other cables that need to be disconnected. After removal, set the electronics other cables that need to be disconnected. After removal, set the electronics
chassis aside. chassis aside.
Removal of the CRT is next. Prepare a soft surface to set the CRT on. Remove the Removal of the CRT is next. Prepare a soft surface to set the CRT on. Remove the
screws attaching the CRT to the bezel, and then remove the CRT. Do not lift or screws attaching the CRT to the bezel, and then remove the CRT. Do not lift or
carry the CRT by the neck or yoke assembly. Avoid contact with the anode button, carry the CRT by the neck or yoke assembly. Avoid contact with the anode button,
which may still have some residual charge on it, (you may wish to discharge it which may still have some residual charge on it, (you may wish to discharge it
again at this point). Set the CRT on the prepared surface. again at this point). Set the CRT on the prepared surface.
Several other preliminary compatibility requirements should now be assessed: Several other preliminary compatibility requirements should now be assessed:
• • Position the CRT so the face is accessible, providing a soft cushion for the Position the CRT so the face is accessible, providing a soft cushion for the
neck and the yoke if they must rest on the work surface. Alternatively, set the neck and the yoke if they must rest on the work surface. Alternatively, set the
CRT face-up in an office-type plastic waste basket, CRT face-up in an office-type plastic waste basket,
is not resting on the neck is not resting on the neck
check to see that the face of the CRT and touchscreen are about the same size, check to see that the face of the CRT and touchscreen are about the same size,
and that the radius of curvature (ROC) of each surface matches well. If both of and that the radius of curvature (ROC) of each surface matches well. If both of
these conditions are not met, you may not have the proper touchscreen for the these conditions are not met, you may not have the proper touchscreen for the
display. Most color displays have standard size CRT's with standard ROC's, display. Most color displays have standard size CRT's with standard ROC's,
and Elo has touchscreens for most of them. and Elo has touchscreens for most of them.
Next, determine if the touchscreen will fit in the bezel without modifications Next, determine if the touchscreen will fit in the bezel without modifications
• •
to the bezel. Modifications, if necessary, should be done without seriously to the bezel. Modifications, if necessary, should be done without seriously
compromising the mechanical integrity of the display. compromising the mechanical integrity of the display.
Lay the touchscreen face-down in the bezel, being careful not to damage the Lay the touchscreen face-down in the bezel, being careful not to damage the
transducers (see Figure 2-1, page 9). Leave the degaussing coil in place, if transducers (see Figure 2-1, page 9). Leave the degaussing coil in place, if
present. The degaussing coil is a hoop, often located between the CRT and present. The degaussing coil is a hoop, often located between the CRT and
bezel, approximately 0.25-inch (6 mm) thick, with a two-wire cable and con- bezel, approximately 0.25-inch (6 mm) thick, with a two-wire cable and con-
nector. The coil was probably unplugged from the power supply earlier. nector. The coil was probably unplugged from the power supply earlier.
If the touchscreen will not fit flush against the lip of the bezel, do not force it. If the touchscreen will not fit flush against the lip of the bezel, do not force it.
An interference fit between the edge of an IntelliTouch touchscreen and some An interference fit between the edge of an IntelliTouch touchscreen and some
of the plastic ribs found in display bezels can pinch and break the small wires of the plastic ribs found in display bezels can pinch and break the small wires
which carry the signals along the edges of the touchscreen or even result in which carry the signals along the edges of the touchscreen or even result in
fracture of the glass after reassembly. fracture of the glass after reassembly.
Disassembling the D Disassem
. Place the touchscreen on the face of the tube, and . Place the touchscreen on the face of the tube, and
bling the Display isplay
making sure that the tube making sure that the tube
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