2. A logic probe is placed on the output of a gate and the display indicator is dim. A pulser is used on each of the input terminals, but the output indication does not change. What is wrong?
Options
A. The output of the gate appears to be open.
B. The dim indication on the logic probe indicates that the supply voltage is probably low.
C. The dim indication is a result of a bad ground connection on the logic probe.
Correct Answer: There is a signal loss to all gates on the node, and the affected node will be stuck in the LOW state.
5. As a technician you are confronted with a TTL circuit board containing dozens of IC chips. You have taken several readings at numerous IC chips, but the readings are inconclusive because of their erratic nature. Of the possible faults listed, select the one that most probably is causing the problem.
Options
A. A defective IC chip that is drawing excessive current from the power supply
B. A solar bridge between the inputs on the first IC chip on the board
C. An open input on the first IC chip on the board
D. A defective output IC chip that has an internal open to Vcc