NEC NDA-24300 manual How to Set the ROM in IC Socket

SYSTEM MAINTENANCE OUTLINE

(3)When a circuit card appears to be faulty, check the following items before replacing it with a spare:

(a)Poor connector contact at the circuit card may be responsible for the fault. Repeat insertion and ex- traction of the circuit card a few times. Clean the connector portion, and recheck for proper operation.

(b)Check the lead wires of vertically-mounted parts (resistors, capacitors, etc.) to ensure they have not shorted each other or broken.

(c)Check the back side of the circuit card to see if there is any short-circuited soldered portion, or mod- ified cross connection wires erroneously left unconnected.

(d)Check the ROMs to ensure proper seating in the IC socket. Figure 2-21shows a leg that is bent and not set in the socket.

A pin is bent, not inserted in the socket.

ROM

SOCKET

Figure 2-21 How to Set the ROM in IC Socket

CHAPTER 2 NDA-24300

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Issue 1