Knowledge of Solid State Digital and Analogue Theory K1 1. Given the supplied logic symbol complete the table below. A B Output 00 01 10 11 2. Given the supplied logic symbol complete the table below. A B Output 00 01 10 11 3. The higher the Q of a tuned circuit, the ________ the bandwidth 4 pts 4pts 4. True or False: An NPN transistor switch has a positive voltage on its emitter and a negative voltage on its base. This transistor is “off”. 1pt 1pt 5. What are the following resistor values? 3 pts 1. Orange 2. Orange 3. Orange 4. Silver 2 pts Answers: 1. Yellow 2. Violet 3. Red 4. Gold4. Gold 1. Brown 2. Black 3. Red 6. How much power will be dissipated by the 12 volt regulator? Assume R1 is 20 ohms. 7. A 24 volt battery has internal resistance of 0.05 ohms. The load connected to it is drawing 16 Amps. How many watts are being dissipated by the battery itself? Show your work. 2 pts 8. Roughly without indicating any levels or numbers, sketch the approximate AC Voltage vs Frequency response graph the following circuit would be expected to produce. 2 pts 9. What is the impedance of a 10 microfarad capacitor, when a 1 kHz signal is applied? Show your work. 2 pts 10. What is the db gain of an amplifier with 25mW input, if it produces 500 Watts output? Round to nearest whole number. 2 pts Knowledge Electronic troubleshooting Techniques K2 1. Computer A has IP address 10.0.0.8 and computer B has IP address 10.0.0.12. Subnet masks for each is 255.0.0.0. What would you type at a DOS prompt on computer A, in order to test whether they can communicate together via the IP network? C:\>_________________ 2 pts 2. You need to replace some soldered components on a circuit board. What steps would you need to follow? The board has arrived in appropriate ESD safe packaging. 6 pts 3. You have observed a fault that disappears after a circuit board has heated up to its normal operating temperature. You don’t have time to allow the circuit to cool and reheat over and over, in order to troubleshoot. What can you do to “zero in” on this fault? 4 pts 4. You have received mixed reports from personnel onboard a ship regarding the details of a fault with one of their systems. What would you do in order to clarify the situation? 2 pts Ability to Read and Interpret Electronic Schematics A2 With respect to the supplied schematic: 1. What is the purpose of T1? 2 pts 2. Describe what CR2 in combination with U1 is doing. 2 pts 3. How many multi-pin connectors are mounted on this circuit board? 2 pts 4. In looking at this schematic, what would be the power rating, and percent tolerance of the resistors? 2 pts 5. What is the purpose of capacitors C1 through C4? 2 pts 6. If pin 16 of U1, which is being used as a comparator, is toggling between +5v and -5V, every second, what would the approximate waveform at TP7 look like? Assume U3 pin 11 is a high impedance, and CR3 has Vf = 0.7Volts. 4 pts Ability to diagnose faults and repair electronic equipment A3 1. You are called in to look at a power supply that is believed to be failing. The fault is that has blown its main fuse. What are some things you may wish to consider when pursuing this repair? 5 pts Powered by TCPDF (www.tcpdf.org) 2. You need to observe a waveform on an oscilloscope, and the unit under test employs a floating ground circuit. What precautions do you take when making this measurement? 4 pts 3. 4. 5. What is the difference between a logic analyzer and a network analyzer? 2 pts You need to make a very sensitive RF signal measurement from a point on a circuit board. What should you consider when doing this? 4 pts Why is it important to have high impedance inputs on some test and measurement equipment? 2 pts