Q1. What are the two types of electrical communications?
A1. Radio and wire.
Q2. What is the main advantage of radiotelegraph communications?
Q3. Why is radiotelephone one of the most useful methods of military communications?
A3. It is direct, convenient and easy to use.
Q4. What are the disadvantages of radiotelephone communications?
A4. Static, enemy interference or a high local noise level.
Q5. What is the main use of a radio teletypewriter?
A5. High speed automatic communications across ocean areas.
Q6. What is facsimile?
A6. The process used to transmit photographs, charts and other graphic information electronically.
Q7. A system is subdivided into what levels?
A7. Set, group, unit, assembly, subassembly, and part.
Q8. In the example 1A6CR3, what is the assembly designator?
Q9. he majority of vlf transmitters are used for what purpose?
A9. Fleet communications or navigation.
Q10. Today the Navy uses lf communications as a segment of what operational system?
A10. Fleet Multichannel Broadcast System.
Q11. Why does the Navy only use the upper and lower ends of the mf band?
A11. Due to the commercial broadcast (AM) band.
Q12. What are the four general types of communications services in the hf band?
A12. Point-to-point, ship-to-shore, ground-to-air, and fleet broadcast.
A message transmitted on several frequencies at the same time is an example of what type of transmission?
Q14. Physically separating receive antennas is an example of what technique?
Q15. When using frequencies above 30 megahertz, you are normally limited to using what range?
A15. Line of sight.
Q16. The naval communications system is made up of what two groups of communications?
A16. Strategic and tactical.
Q17. What are the five most prominent communications modes of operation?
A17. Simplex, half-duplex, semiduplex, duplex, and broadcast.
Q18. What four switched networks are part of the defense communications system?
A18. AUTOVON, AUTOSEVOCOM, AUTODIN, and DSSCS.
Q19. What two elements support only designated Navy requirements?
A19. HICOM and NORATS.
Q1. What are the four basic transmitter types?
A1. Am, fm, cw, ssb.
Q2. What is the function of the oscillator in a cw transmitter?
A2. It generates an rf carrier at a given frequency within required limits.
Q3. What is the final stage of a transmitter?
A3. Power amplifier.
Q4. What purpose does a microphone perform in an AM transmitter?
A4. It converts audio (sound) into electrical energy.
Q5. In an fm transmitter, when does an oscillator generate only a steady frequency?
A5. When no modulation is present.
Q6. What is a harmonic?
A6. It is an exact multiple of the basic or fundamental frequency.
Q7. If the fundamental frequency is 200 megahertz, what is the third harmonic?
A7. 600 megahertz.
Q8. Why are frequency multipliers used?
A8. To obtain higher carrier frequencies.
Q9. What are two advantages of ssb transmission?
A9. It saves power and frequency bandwidth.
Q10. What is the purpose of an order-wire circuit?
A10. For operator-to-operator service messages and frequency changes.