Do I need to remove the front panel on my 1780R/1781R to change the graticule light bulbs?
No. To gain access to the graticule light bulbs the metal strip under the two CRT's must be removed. Loosen the set screws on the SCALE, FOCUS, INTENSITY, VERT POS, and HORIZ POS knobs. Slide the knobs off of their shafts. Use pliers to grip the lip around the hole for SCALE adjustment shaft. Carefully pull the metal strip forward until it pops out. Long needle nose pliers can be used to remove the bulbs. Wrapping the tips with masking tape will prevent the bulbs from breaking. To access the graticule bulbs that lie behind the plastic light guide remove the 3 screws that hold the plastic CRT Frame Outer Bezel to the chassis. Then gently pull forward on the lower edge of the bezel taking care not to disconnect the wire to the PROBE BNC connector. Remove the light guide that covers the defective bulb. Then use long nosed pliers to remove the bulb. After new bulbs have been installed reverse the removal procedure to reinstall all the parts.
FAQ ID 58151