JVC 250 service manual CRT/Yoke Assemblies - Remove and Replace

Chapter 5---Electronics

CRT/Yoke Assemblies - Remove and Replace

Three CRT/Yoke Assemblies are located in the CRT Assembly area below the card cage (see Figure 5-30).

WARNING!!! Handle the CRT/Yoke Assemblies with extreme caution. If they are dropped, they can implode and flying glass can cause severe injury to personnel. Be careful not to bump or drop the CRT. Immediately after removal, place the CRT/Yoke in a safe area.

Procedure to remove a CRT/Yoke Assembly:

Tools Needed

#0 Pozi-drive Phillips-head screwdriver

Parts Needed

CRT p/n 105199

To remove and replace a CRT:

1.Power OFF the projector by IR Remote or PC, and allow the cooling fans to run until they shut off automatically.

2.Turn the AC Circuit Breaker to the OFF position and unplug the AC Power Cord.

3.Remove front and rear covers.

4.Tilt the Electronic Module up and lock it in place.

5.Loosen the two Pozi-drive Phillips-head screws from the top of the High Voltage Power Supply cover. Remove the one Pozi-drive Phillips-head screw at the bottom of the cover.

6.Remove the CRT Anode cable of the CRT being replaced from the High Voltage Power Supply.

7.Disconnect the Yoke plug and cable harness from the Scan Reversal PCB for the appropriate CRT (see Figure 5-25).

8.Remove the wires from the cable clamp for the CRT/Yoke Assembly being removed.

9.Loosen the CRT Holder Ring (knurled knob in Figure 5-29).

NOTE: The CRT Holder Ring should be only hand-tight. If it is not possible to remove by hand, place a Flathead screwdriver in the slots on the CRT Holder Ring and tap lightly to help loosen it. Do not use a tool of any kind to tighten this ring - hand tighten only.

10.Carefully remove the CRT/Yoke Assembly by sliding it backward and upward as far as possible before unplugging the CRT socket connector from the neck.

Model 250 Service Manual 5-57