1. General Licensing Class Your Receiver Lake Area Radio Klub Spring 2012

2. 2 Amateur Radio General Class Element 3 Course Presentation  ELEMENT 3 SUB-ELEMENTS (Groupings) 1 - Your Passing CSCE 2 - Your New General Bands 3 - FCC Rules 4 - Be a VE 5 - Voice Operations 6 - CW Lives 7 - Digital Operating 8 - In An Emergency 9 - Skywave Excitement

3. 3 Amateur Radio General Class Element 3 Course Presentation  ELEMENT 3 SUB-ELEMENTS (Groupings) 10 - Your HF Transmitter  11 - Your Receiver 12 - Oscillators & Components 13 - Electrical Principles 14 - Circuits 15 - Good Grounds 16 - HF Antennas 17 - Coax Cable 18 -RF & Electrical Safety

4. Your Receiver  The simplest combination of stages that implement a superheterodyne receiver is HF oscillator, mixer, detector. (G7C07) Simple Generic Superheterodyne Receiver

5. Your Receiver Simplest combination HF oscillator mixer detector

6. Your Receiver  A mixer is the circuit used to process signals from the RF amplifier and local oscillator and send the result to the IF filter in a superheterodyne receiver. (G7C03) IF Amplifier Stages Single conversion receiver Dual conversion receiver

7. Your Receiver  A product detector is the circuit is used to combine signals from the IF amplifier and BFO and send the result to the AF amplifier in a single-sideband receiver. (G7C04)  Heterodyning is another term for the mixing of two RF signals. (G8B03) Very simple mixer

8. Your Receiver  In a receiver the Mixer stage combines a 14.250 MHz input signal with a 13.795 MHz oscillator signal to produce a 455 kHz intermediate frequency (IF) signal. (G8B01) A Mixer circuit is used to process signals from the RF amplifier and local oscillator and send the result to the IF filter in a super heterodyne receiver. In this mixer the output is the sum and the difference of the two applied signals: The sum would be 14.250 + 13.795 or 28.045 MHz The difference would be 14.250 - 13.795 or 0.455 MHz Filtering removes the undesired frequency Mixer First IF amp. Local oscillator 13.795 MHz 14.250 MHz 455 kHz

9. Your Receiver  If a receiver mixes a 13.800 MHz VFO with a 14.255 MHz received signal to produce a 455 kHz intermediate frequency (IF) signal, a 13.345 MHz signal will produce an image response in the receiver. (G8B02) To prevent this many receivers use a tuned preamplifier before the mixer input (sometimes called a preselector).  An advantage of a receiver Digital Signal Processor IF filter as compared to an analog filter is that a wide range of filter bandwidths and shapes can be created. (G4C12)  The following is needed for a Digital Signal Processor IF filter. (G7C09)  An analog to digital converter  A digital processor chip  A digital to analog converter All of the choices are correct.

10. Your Receiver  One use for a Digital Signal Processor in an amateur station is to remove noise from received signals. (G4C11)  Digital Signal Processor filtering is accomplished by converting the signal from analog to digital and using digital processing followed by converting back to analog. (G7C10) Basic Digital Signal Processing (DSP) System DSP speaker

11. Your Receiver  One reason to use the attenuator function that is present on many HF transceivers is to reduce signal overload due to strong incoming signals. (G4A13) Dual function switch: Pre-amp & Attenuator. Icom 7000

12. Your Receiver  The purpose of the "notch filter" found on many HF transceivers is to reduce interference from carriers in the receiver passband. (G4A01)

13. Your Receiver  A Digital Signal Processor (DSP) filter can perform automatic notching of interfering carriers. (G4C13)  A discriminator circuit is used in many FM receivers to convert signals coming from the IF amplifier to audio. (G7C08) FM receivers have different types of circuits than the superheterodyne receivers designed for AM, CW and SSB. Discriminator circuitFrequency to voltage conversion

14. Your Receiver  An S meter is found in a receiver. (G4D06) Most commercial receivers have an S meter.  An S meter measures received signal strength. (G4D04) “S” Meters are based on S9 representing 50uV

15. Element 3 General Class Question Pool Your Receiver Valid July 1, 2011 Through June 30, 2015

16. G7A07 What is the simplest combination of stages that implement a superheterodyne receiver? A.RF amplifier, detector, audio amplifier B.RF amplifier, mixer, discriminator C.HF oscillator, mixer, detector D.HF oscillator, pre-scaler, audio amplifier

17. G7C03 What circuit is used to process signals from the RF amplifier and local oscillator and send the result to the IF filter in a superheterodyne receiver? A.Balanced modulator B.IF amplifier C.Mixer D.Detector

18. G7C04 What circuit is used to combine signals from the IF amplifier and BFO and send the result to the AF amplifier in a single-sideband receiver? A.RF oscillator B.IF filter C.Balanced modulator D.Product detector

19. G8B03 What is another term for the mixing of two RF signals? A.Heterodyning B.Synthesizing C.Cancellation D.Multiplying

20. G8B01 What receiver stage combines a 14.250 MHz input signal with a 13.795 MHz oscillator signal to produce a 455 kHz intermediate frequency (IF) signal? A.Mixer B.BFO C.VFO D.Discriminator

21. G8B02 If a receiver mixes a 13.800 MHz VFO with a 14.255 MHz received signal to produce a 455 kHz intermediate frequency (IF) signal, what type of interference will a 13.345 MHz signal produce in the receiver? A.Local oscillator B.Image response C.Mixer interference D.Intermediate interference

22. G4C12 Which of the following is an advantage of a receiver Digital Signal Processor IF filter as compared to an analog filter? A.A wide range of filter bandwidths and shapes can be created B.Fewer digital components are required C.Mixing products are greatly reduced D.The DSP filter is much more effective at VHF frequencies

23. G7C09 Which of the following is needed for a Digital Signal Processor IF filter? A.An analog to digital converter B.A digital to analog converter C.A digital processor chip D.All of the these answers are correct

24. G4C11 Which of the following is one use for a Digital Signal Processor in an amateur station? A.To provide adequate grounding B.To remove noise from received signals C.To increase antenna gain D.To increase antenna bandwidth

25. G7C10 How is Digital Signal Processor filtering accomplished? A.By using direct signal phasing B.By converting the signal from analog to digital and using digital processing C.By differential spurious phasing. D.By converting the signal from digital to analog and taking the difference of mixing products

26. G4A13 What is one reason to use the attenuator function that is present on many HF transceivers? A.To reduce signal overload due to strong incoming signals. B.To reduce the transmitter power when driving a linear amplifier. C.To reduce power consumption when operating from batteries. D.To slow down received CW signals for better copy.

27. G4A01 What is the purpose of the “notch filter” found on many HF transceivers? A.To restrict the transmitter voice bandwidth. B.To reduce interference from carriers in the receiver passband. C.To eliminate receiver interference from impulse noise sources. D.To enhance the reception of a specific frequency on a crowded band.

28. G4C13 Which of the following can perform automatic notching of interfering carriers? A.Band pass tuning B.A Digital Signal Processor (DSP) filter C.Balanced mixing D.A noise limiter

29. G7C08 What type of circuit is used in many FM receivers to convert signals coming from the IF amplifier to audio? A.Product detector B.Phase inverter C.Mixer D.Discriminator

30. G4D06 Where is an S-meter found? A.In a receiver B.In a SWR bridge C.In a transmitter D.In a conductance bridge

31. G4D04 What does an S-meter measure? A.Conductance B.Impedance C.Received signal strength D.Transmitter power output