1. 1 General Licensing Class The W5YI Group Power Point presentations are authorized for use by individuals who register with The W5YI Group’s HamInstructor.com program. The presentations are provided by Master Publishing and The W5YI Group and include material that is covered by U.S. and International copyrights. They are intended solely for the use of Registered Instructors using the Gordon West, WB6NOA, Technician Class, General Class, and Extra Class study manuals to teach FCC Amateur Radio Licensing Classes. Registration through HamInstructor.com constitutes a Licensing Agreement between The W5YI Group and the registered instructor under which the instructor agrees not to copy or distribute the Power Point presentations to unauthorized users.

2. 2 General Licensing Class Good Grounds Valid July 1, 2015 Through June 30, 2019

3. 3 3 Amateur Radio General Class Element 3 Course Presentation  ELEMENT 3 SUB-ELEMENTS (Groupings) Your Passing CSCE Your New General Bands FCC Rules Be a VE! Voice Operation CW Lives! Digital Operating In an Emergency Skywave Excitement!

4. 4 4 Amateur Radio General Class Element 3 Course Presentation  ELEMENT 3 SUB-ELEMENTS (Groupings) Your HF Transmitter Your Receiver Oscillators & Components Electrical Principles Circuits  Good Grounds HF Antennas Coax Cable RF & Electrical Safety

5. 5 Good Grounds G4C05 Nothing worse than petting Fido while going on the air with your new high frequency installation and seeing a blue arc from your D-104 microphone to his metal nametag, accompanied by a yelp! Welcome to RF floating along the chassis ground of your equipment. Using wire to ground HF equipment may create an antenna-like circuit that looks like an open circuit to earth ground. Round ground wires may also behave like wire coils, developing a reactance at specific frequencies, and blocking the ground connection to that cold water pipe. This blocking action is called impedance. Always ground your equipment with flat braid or copper foil, using the shortest run possible to an actual earth ground. In some cases, this may not be possible. In such a situation you might try a device called an artificial ground, which makes a low impedance, series resonant circuit out of any ground wire you do have. Sometimes acquiring a good RF ground is an art form and may require patience and persistence

6. 6 Good Grounds G4C07A safe way to keep all of your equipment at the same potential is to run a strip of copper foil at the rear of your station operating desk, and then small, one inch wide copper foil tags going to each radio and accessory. These tags should be long enough to allow you to pull out the equipment for servicing, and then accordion-up when you push the gear back into place. Connecting all of your equipment grounds together in this way (a procedure known as bonding) will help keep stray RF out of your station.

7. 7 Good Grounds G4C09I have several HF transceivers at the shack, and all copper foil ground connections go to a single ground point. From that point, the flattened copper pipe goes through the wall and into the earth. Grounding to a single point will minimize ground loops. If you ever have a new fancy audio stereo system installed in your vehicle, the savvy tech will run all component grounds to a single ground point to minimize ground loops.

8. 8 Good Grounds G4C10 You are on the air for the first time and everyone reports you sound loud and sort of clear, but with a hum behind your signal. Sounds like a ground loop to me. This can be cured with good copper foil grounding interconnected to each and every piece of metal equipment you have on your desk. This includes that big computer, too. Grounding Equipment

9. 9 Good Grounds G4C06If you notice a tingle when you touch anything metal on your equipment during transmit, it is a sign that a resonant ground connection is causing high voltages to back up onto the case of the radio. Time to switch over to some 3-inch wide copper foil. That’s what Gordo and Eric use at their stations. Copper foil ground strap provides a good surface area ground.

10. 10 Good Grounds G4A15 Not only can radio frequency interference potentially cause problems with your neighbors’ electronics, but sometimes you can cause interference to yourself. This interferrence can manifest itself in a number of unexpected and “interesting” ways! “RF in the shack” is the general term used to describe a whole catalog of undesired symptoms. But they can usually be resolved with some logic and persistence. The two main ingredients of harmful RF are an antenna of some sort and a rectifier “detector” of some sort. These components may not be obvious. Any conductor such as a microphone cable, computer data cable, or your transmission line (if it’s not properly decoupled from your transmitting antenna) can be an antenna. A detector can be anything from a microphone preamplifier to a cold solder connection. When RF in a conductor encounters a detector, a DC or audio voltage is created, which looks just like “real” audio to your transmitter. This audio can keep your VOX keyed, create distortion, or do “a number” on digital signals. A few ferrite beads slipped over suspect cables can do wonders to tame RF in the shack. Sometimes just rearranging cables can fix things too.

11. 11 Good Grounds G4C01When you begin operating on General Class frequencies, your powerful, high-frequency SSB transceiver fed into a roof-top antenna system will probably create audio-frequency interference to your own home electronics and those of your neighbors. Bypass capacitors – usually 0.01 mF – will sometimes help minimize this problem when strategically placed across and onto speaker wires and wiring harnesses inside the affected home electronic systems. It’s not a cure-all, but bypass capacitors are your first step in resolving interference complaints on a case-by-case basis.

12. 12 Good Grounds G4C08You can get some terrific audio DSP speakers to add on to older equipment that does not have audio DSP capability. If the speakers are amplified, sometimes RF transmit sounds come out over the speaker itself. You can minimize this common-mode current on the audio cable by placing ferrite beads around the cable. Use ferrite beads around all the computer and data cables, too. Snap-on ferrite choke.

13. 13 Good Grounds G4C03Single-sideband sounds like distorted speech coming over a public address system or certain home electronics. However, double sideband AM CB radio transmissions usually come through loud and clear, so these are easily distinguished from SSB ham transmissions. If someone says you are causing interference, ask the big question: “Does it sound clear, or does it sound garbled?”

14. 14 Good Grounds G4C04CW transmissions come over a PA or home electronics system as on-and-off humming or clicking sounds. There is no mistaking the sound of CW.

15. 15 Good Grounds G4C02About once every 6 months I go around and tighten up all connections on my ham equipment. Most important is the tightening-up of the copper ground foil connections to the back of my rig. An intermittent RF ground will sometimes create broadband radio frequency noise that will magically go away as soon as you give that nut a little clockwise crank.

16. 16 Good Grounds G4E07The noise blankers on most HF mobile transceivers do a nice job of getting rid of sparkplug pops. But right where you want to operate on the “Gordo net” frequency at 7250 kHz you hear a steady, raspy carrier that only goes away when you shut off the ignition. Guess what – it may be your vehicle’s onboard computer. Sometimes these computer noises go all the way up into the 2 meter band as well. Relocating the antenna may help. While I have heard of vehicle computer interference on the VHF and UHF bands, luckily I almost never hear of this problem down on HF.

17. 17 Valid July 1, 2015 Through June 30, 2019 Good Grounds Element 3 General Class Question Pool

18. 18 G4C05 What might be the problem if you receive an RF burn when touching your equipment while transmitting on an HF band, assuming the equipment is connected to a ground rod? A.Flat braid rather than round wire has been used for the ground wire. B.Insulated wire has been used for the ground wire. C.The ground rod is resonant. D.The ground wire has high impedance on that frequency.

19. 19 G4C07 What is one good way to avoid unwanted effects of stray RF energy in an amateur station? A.Connect all equipment grounds together. B.Install an RF filter in series with the ground wire. C.Use a ground loop for best conductivity. D.Install a few ferrite beads on the ground wire where it connects to your station.

20. 20 G4C09 How can a ground loop be avoided? A.Connect all ground conductors in series. B.Connect the AC neutral conductor to the ground wire. C.Avoid using lock washers and star washers when making ground connections. D.Connect all ground conductors to a single point.

21. 21 G4C10 What could be a symptom of a ground loop somewhere in your station? A.You receive reports of “hum” on your station’s transmitted signal. B.The SWR reading for one or more antennas is suddenly very high. C.An item of station equipment starts to draw excessive amounts of current. D.You receive reports of harmonic interference from your station.

22. 22 G4C06 What effect can be caused by a resonant ground connection? A.Overheating of ground straps. B.Corrosion of the ground rod. C.High RF voltages on the enclosures of station equipment. D.A ground loop.

23. 23 G4A15 Which of the following can be a symptom of transmitted RF being picked up by an audio cable carrying AFSK data signals between a computer and a transceiver? A.The VOX circuit does not un-key the transmitter. B.The transmitter signal is distorted. C.Frequent connection timeouts D.All of these choices are correct.

24. 24 G4C01 Which of the following might be useful in reducing RF interference to audio frequency devices? A.Bypass inductor. B.Bypass capacitor. C.Forward-biased diode. D.Reverse-biased diode.

25. 25 G4C08 Which of the following would reduce RF interference caused by common-mode current on an audio cable? A.Placing a ferrite bead around the cable. B.Adding series capacitors to the conductors. C.Adding shunt inductors to the conductors. D.Adding an additional insulating jacket to the cable.

26. 26 G4C03 What sound is heard from an audio device or telephone if there is interference from a nearby single sideband phone transmitter? A.A steady hum whenever the transmitter is on the air. B.On-and-off humming or clicking. C.Distorted speech. D.Clearly audible speech.

27. 27 G4C04 What is the effect on an audio device or telephone system if there is interference from a nearby CW transmitter? A.On-and-off humming or clicking. B.A CW signal at a nearly pure audio frequency. C.A chirpy CW signal. D.Severely distorted audio.

28. 28 G4C02 Which of the following could be a cause of interference covering a wide range of frequencies? A.Not using a balun or line isolator to feed balanced antennas. B.Lack of rectification of the transmitter’s signal in power conductors. C.Arcing at a poor electrical connection. D.Using a balun to feed an unbalanced antenna.

29. 29 G4E07 Which of the following may cause interference to be heard in the receiver of an HF radio installed in a recent model vehicle? A.The battery charging system. B.The fuel delivery system. C.The vehicle control computer. D.All of these choices are correct.