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RicardoJM
02-09-2009, 06:45 PM
Lets use this thread for week #3 homework assignment and class questions.

RockRunner
02-10-2009, 10:45 PM
I missed last night, I am so bummed. I am going to keep reading and come next Monday. It may not be PC to say right now but i hate work sometimes:mad:

Groucho
02-11-2009, 07:43 AM
These are repeats from the notes I gave for last Monday night. I will be posting others during the week, so stay tuned for them.

Begin notes:

Some other types of fun things we will do are learn a little bit about operating practices on the air, so that everyone knows a little about what to expect when you get on the air for the first few times and understand what is being said.

For the Technician license, you will probably spend most of your early operating on the 2M band using repeaters. A couple of good things to know are the meanings of the following:
Full-Quieting--This means that on FM transmissions where the incoming signal is sufficient to engage the receiver limiters - thus eliminating the noise due to amplitude fluctuations, or the incoming signal is clear and without any other static or interference.
Over--Operators say "over" when there is an expected response from the other station.
Clear--Amateur operators say clear instead of the common term "out" when no response is expected from the other station, and the operator is done transmitting for a period of time or is done being on the radio. "Clear on your final" indicates that the operator will listen for the other stations last transmission and then is done transmitting or being on the radio.
Rag-chewing--Rag chewing is just people having casual conversations on the air. They are not trying to get many contacts as is the case for contests where stations will only exchange callsigns, signal reports and maybe handles. Rag chewing is more casual, and can go on and on.

Usually on repeaters operators give their callsigns when they end their transmission, or as often as the repeater gives its callsign, whichever comes first. Because the repeater is required to give its call every ten minutes, if all of the operators rag-chewing on the repeater do a roundtable call ID then everyone is in compliance. You will hear them saying "WØIIN, 'cause the repeater did". Just an informal way to remind people to give their call.

Passing the mike--This is a common error new operators will do when they are nervous. In face-2-face conversations, it is easy to know who was talking to who, and who is next. In radio conversations, the microphone needs to be "passed" to the next operator or some operators will be left out and some will talk forever. "Passing" the mike is as easy as saying "Ok, that's what I had to say, KØNAK over to you". At first callsigns will be all jumbled numbers and letters in your head, but after a while you will pick up a few. It does not matter who you pass the mike to, as long as you indicate who you are passing it to. That way, if the next operator has nothing to say, they can pass it to someone else, instead of ten operators trying to talk all at once or dead silence 'cause no one knows who is next.

Now a little about HAM-speak for all the bands. Q-signals have their root in telegraphy when letters and numbers all cost money to send. Abbreviated versions of what needs to be said made it easier and cheaper to say the same thing. Some q-signals we all need to learn, as well as some abbreviated word are:

QSO-a contact made with another station. You'll hear "thanks for the QSO" (pronounced Q-SO)
QSL-confirmation. When asked as a question, it means "did you understand?", when said as a statement it means "I understand".
QRM-the M stands for Man-made interference such as another operator who is trying to talk at the same time you are
QRN-the N means Natural interference such as power line static, lightning, and poor band conditions
QSB-Fading signals. that means that you may hear them really good for a few seconds, then they fade out, and then they are back to good again
QRP-Decrease power, or more often the term for operating with very little (less than 100W) power
QRO-Increase power
QSY-change frequency. When said as a question, it means "do you want to change frequency?" and when stated it means "lets change frequency"
QRX-hang on for a minute, I'll be right back (Going to get a beer)

XYL-wife
yl-young lady
om-old man
sked-schedule
73-see you later
88-hugs and kisses
fine business-another way to acknowledge something
roger, roger-another way of acknowledging
Hi, Hi-radio laughter. Indicative of a joke, or laughing at something that was said. For example, if someone says "I bet he is faster than you doing that obstacle. Hi, Hi" they are saying it as a joke.

And a double-secret bonus item to know? Life's too short for QRP. If Bruce decides to join us for some real life stories, you will impress him with that.

Hope that can give us some fun things to incorporate into the class. '73

Groucho
02-11-2009, 02:13 PM
FYI-- Since it bears merit to another thread in the forum, I will reemphasize factual statements I made last Monday night. In our class, we covered that there are other non-licensed radio services that do not have the provisions for use that Amateur Radio does. These provisions make Amateur Radio much more attractive as a means of communication. And much more fun!;)

FCC regulations Part 95, subpart D relate to the Citizens Band (CB) radio service.
Part 95.409 asks the question "What equipment may I use at my CB station."
As I stated in class Monday night (as well as class last year, for those who attended) any radio used in the CB service MUST be certified by the FCC. Otherwise, it is illegal. The regs read "(a) You must use an FCC certified CB transmitter at your CB station."

Part 95.410 asks the question "How much power may I use?"
I stated (incorrectly by 1 watt) that CB's were limited to 5 Watts peak power. In fact, the regulations say that it is 4 watts peak power. Otherwise it is illegal. The regs read "(a) Your CB station transmitter power output must not exceed the following values under any conditions: AM (A3)--4 watts (carrier power) SSB--12 watts (peak envelope power)" Almost all of the lower end CB trancievers (transmitter/receiver combo) use AM to transmit and receive. Most often it is only the higher end ones that have the selectability for SSB (Single SideBand)

Part 95.411 Asks the question "May I use power amplifiers?"
I stated that amplifiers were illegal. The regs read "(a) You may not attach the following items (power amplifiers) to your certified CB transmitter in any way: (1) External radio frequency (RF) power amplifiers (sometimes called linears or linear amplifiers);

So when someone says "why get a HAM radio when you can do all the same things with a CB for half the cost and no license" , you as licensed operators can tell them just how different the two are. :thumb::cheers:

farnhamstj
02-11-2009, 06:28 PM
What are the chapters to be familiar with this week?

Groucho
02-11-2009, 09:48 PM
OK, so let me get the nitty-gritty out of the way.

The reading assignment for class #2 will be:
Chapter 3--Operating Station Equipment
Transmitters and Receivers
Station Fundamentals
RF Interference (RFI)

Chapter 4--Communicating With Other Hams
Contact Basics
Band Plans
Making a Contact
Nets and Emergency Operating
Special Modes and Techniques

We will be doing some in class activities, such as learning about SingleSideBand (SSB) and the difference between Lower SideBand (LSB) and Upper SideBand (USB).

One thing to learn about radio:More power does NOT let you hear a repeater better, and if a repeater is already full-quieting improving the receive antenna will not improve a weak station transmitting through a repeater. You are only able to control how good your signal is coming out of your radio and into the air (antenna and feedline). Everything else is left to chance. If a poorly setup station is trying to reach you a few blocks down the road on 2M simplex (we'll cover what simplex is), you will not do anything to improve that station's signal.

Know what harmonic and overload interferences are. Know how to identify possible RFI producing devices around the home. Know items that can be of help in suppressing RFI.

KNow about station setup. What gets hooked up to what and in what order. Remember, the test may ask about components that are single purpose in nature--HINT transmitter and receiver vs transceiver. Know what daisy-chaining is and why it is important NOT to do it with regards to station ground.

Know what high-pass, low-pass and band-pass filters are and how they work (meaning what are they supposed to filter OUT). What are ferrite cores?

Know what the difference between simplex and repeater operations. What are CTCSS tones? What is a repeater directory and how do we use it? What does it mean if a repeater is OPEN? What about input and output frequencies for repeaters? What are some of the q-signals you may use from time to time, and know a little history why these were used in the first place. Be able to answer "What is your QTH?" if you are at (a) at home (b) at work (c) driving

How does Amateur Radio support the emergency services worldwide? What are nets? What is the purpose for "checking-in" if there is no net traffic? What exactly is RACES and ARES?

What is Echolink? What is IRLP? How do they work? Is this considered cheating in HAM radio circles? What is APRS? (www.findu.com) What is CW? SSB (LSB & USB)? Phone? Are there segments of the band where each are allowed?

Hopefully this gives some idea of the topics we will cover. Hopefully, if everyone comes to class prepared (Oleg:D), we can spend more time on actual activities and less time where I am talking, boring everyone.:blah:

Groucho
02-18-2009, 11:33 AM
Reading for Class #3 will be:

Radio and Electronics Fundamentals (Chapter 2)

Radio Safety (Chapter 7)

Be prepared to go over OHMS LAW, safety around antennas and towers, and what happens if you aren't safe. We will cover this as fast as possible, so make sure everyone tries to come to class prepared with specific questions about OHMS LAW and safety, so we don't spend any more time on it than necessary.

MDH33
02-18-2009, 11:38 AM
Since we didn't have any time on the 16th to cover Chapter 4, will that be covered along with CH 2 and 7 on the 23rd?

Groucho
02-18-2009, 12:01 PM
Also be prepared to ask more questions like Ige did about the difference between antennas on your vehicle.

We will go over what radiation patterns and TOA (Take Off Angles) are, and why it is important to determine the type of communication desired is. Know the difference between a 5/8 wave, a 1/2 wave and a 1/4 wave vertical antenna are.

Some reading:
The typical groundplane antenna is 1/4, 1/2 or 5/8 wavelength long. The different length have different characteristics.

The 1/4 will be shorter than the 1/2 or 5/8 wavelength antenna and will have a higher take-off-angle (shorter skip distance). On the other hand the antenna may work better in a valley. (The signals will shoot out of the valley. A 5/8 will maybe shoot the signals straight in to the mountains). The picture shows a 1/4 wave antenna shown by the dotted line and a 5/8 wave antenna shown by the solid line. Notice how the two differ in their TOA.

12014

Skip distance and Radiation angle (TOA)--
This will be a very easy explantion of how Radiation angle works and how this will effect HF radiocommunication below 30 mhz. It also applies to VHF but on a much lesser scale.

Every antenna has a radiation-pattern. This pattern describes which angle the signal will leave/enter your antenna. So before you make/buy an antenna, you need to know the purpose of your radiocommunication. If you want to make long distance contacts (DX) (over etc 3000 miles on HF, 30+ miles on VHF), you will need an antenna with low radiation angle (Take off angle = TOA).

If your purpose is shorter range contacts in your local area (10 miles or less, or varied terrain with lots of highs and lows for VHF/UHF) you want an antenna with high angle of radiation. That way the signal will go straight up to the atmosphere and right down.

The picture below will illustrate this. A and B are good for long distance contacts. That could be a vertical antenna with low radiation angle or an dipole that’s elevated atleast 1 wavelength above ground. The C example may be a low elevated dipole (< 1/2 WL over ground) for local contacts. For you can see the signal will go straight up, and straight down.

12015

Horizontal dipoles, long wire’s , yagi’s and other horizontal antennas will work so good you want it to work by deciding the height of the antenna. A rule of thumb is if you want a long skip distance, you have to put the antenna at least 1 wavelength above ground. (20 meters on 14 mhz). Below is a "Radiation Pattern", illustrating how the signal will be radiated from the antenna, based on how high the antenna is. In this example, both the yagi and the dipole are at 69 feet above the ground. It can be seen that the dipole has a much higher TOA than the yagi. Therefore, the dipole will be better for shorter communications with respect to the yagi.

12016

Groucho
02-18-2009, 12:04 PM
Since we didn't have any time on the 16th to cover Chapter 4, will that be covered along with CH 2 and 7 on the 23rd?

More uses of terminology. How to start, stop, and confidently carry on QSO's. Good etiquette. How the hobby of Amateur radio can be more than sitting in the basement. Contests, field days, experimenting, etc. Nets, IRLP, band plans.

Look for a few more notes to come.

MDH33
02-18-2009, 12:31 PM
So, would a horizontal antenna on your vehicle be a bad idea since you cannot get it high enough into the air to account for skip distance?

Groucho
02-18-2009, 01:07 PM
So, would a horizontal antenna on your vehicle be a bad idea since you cannot get it high enough into the air to account for skip distance?

Most mobile antennas are vertical for the plain fact that it is easier to do that than have a horizontal antenna due to space and mounting requirements. Any signal will skip, it just depends on how high and how far. Many HAM operators who participate in emergency services have antennas that are horizontally polarized antennas on their vehicle. Just depends on what you want to do.

You would still have success with a wire dipole on your car with the feedpoint over the sunroof. If you could have the wire go from front to back, and elevated off the car 12" or so parallel with the ground, I imagine you would have the equivalent of what is known as NVIS, or Near Vertical Incidence Skywave. That is where signals are sent up almost vertical so that when the bounce of the levels of the atmosphere they come down almost vertical. That way, a short range of communication is accomplished. While NVIS is used primarily on the 80M and 40M bands, it illustrates what TOA you might have with the aforementioned dipole on the roof.

Try it. It may prove to work really good.

DaveInDenver
02-21-2009, 09:18 AM
Nathaniel would like me to cover the electronics topics and I am happy to do so. But he wants to cover a lot in class #3, there are a few key points that you guys need to hear still (just in concept).

The class will have to move if we want to cover what's left in 2 hours! I plan to run through all of this in an hour to an hour and half, leaving time for a break and for Nathaniel (and Bruce?) to demonstrate more about operation. I've taken semester-long, 3 hour classes on just one of these things, so to talk about 125 years of radio and electronics in 60 minutes is gonna be overwhelming to say the least!

So please be sure to read about a few things that I would rather answer if you don't understand than to talk in any depth about.

Read and think about the follow things:

Ohm's Law
Propagation
Frequency and Wavelength
Electromagnetic fields
Radiation Patterns
Voltage, Current and Resistance
Impedance, Attenuation
Ohm's Law
Conductivity, Emissivity
Polarization, Directionality, Reciprocity, Reflectance
Components (conductors, insulators, resistors, capacitors, inductors, semiconductors)
Power, Heat
Ohm's Law

Last time I talked about this I know it was too detailed, but a radio operator needs to at least be aware that certain things exist so that you can look it up if you want or need to.

If you have questions about things now, please post them up and we can hash through them before getting to Stevinson. W0IIN has given you some nice things to start digesting.

MDH33
02-23-2009, 08:50 AM
IH8Math :confused:

so I made this graphic to help me remember some of this stuff. Now that I have the image in my head, I haven't missed any of the Ohm's law, Power, wavelength questions on the practice tests. :hill:

http://mdhuber.smugmug.com/photos/479260058_Vxybh-M.jpg

DaveInDenver
02-23-2009, 09:52 AM
so I made this graphic to help me remember some of this stuff. Now that I have the image in my head, I haven't missed any of the Ohm's law, Power, wavelength questions on the practice tests.
Whatever it takes to memorize Ohm's Law, there will be something on the test about it and you only get what's in your head on the test, no reference sheets.


Power is as easy as pie to remember. Really. The formula for power is P = I x E, see how it's easy as pie. Who doesn't like pie?



<IGNORE>

Some Technical Stuff

FWIW, I wonder how many people are confused about the 'E' part of the formulas, since I think many people are taught in physics class that Ohm's Law is V = I x R. Why 'E' and not 'V'? The 'E' means electromotive force (i.e. EMF), which is measured in volts (V). But sometimes EMF is simply referred to as voltage. But since the formula uses 'I' as the representation for flow of electronic charge (i.e. current, measured in amperes (A)), it's most correct to use the forcing mechanism and not the measuring unit for charge potential. This is all some of the vagueness of engineering and science. Where Ohms can mean resistance and impedance, which are sorta the same, but not really.
</IGNORE>

nuclearlemon
02-23-2009, 09:58 AM
i just don't understand where the heck they come up with the letters since they don't have anything to do with the word itself. that's what screws me up.

MDH33
02-23-2009, 10:04 AM
yup, me too. That's why I needed to see it with the units rather than just the letters. It may be 3rd grade math, but it just doesn't seem to stick anymore. :hill:

DaveInDenver
02-23-2009, 10:15 AM
yup, me too. That's why I needed to see it with the units rather than just the letters. It may be 3rd grade math, but it just doesn't seem to stick anymore. :hill:
Like I mention, the formula is correct for physical mechanisms.

E = I x R

If you want units, it would be

V = A x Ω.

That is not really a formula, though (and hard to remember too).

The way a scientist would write Ohm's Law is the physical things with units in parenthesis.

IOW:
E(V) = I(A) x R(Ω)

And if you want the reasoning behind the letters, the individual parts of the formula are:

EMF. This is a measure of electrical charge force. It would take a description of electromagnetic fields to understand from where charge potential stems. Just understand it's magic due to the fact that electrons and protons have a basic electrical charge.
http://upload.wikimedia.org/math/9/3/6/936ad62452c49caf21697dd0b6ebe877.png

So the lower case epsilon (ε) in upper case is 'E'

The flow of electrical charges is current, which is defined by:
http://upload.wikimedia.org/math/d/0/e/d0ebe45e0d4ee6804adb323de39bf364.png

The 'I' is just a variable that everyone agreed would represent the derived formula that describes that a change in charge per time is a current.

And D.C. (direct current) resistance is just R, that is a fundamental, but is defined as a function of length, area and resistivity ρ. Resistivity is a characteristic of a material and really can't be described beyond a concept. But it can be measured if you know voltage and current.
http://upload.wikimedia.org/math/9/5/5/95576da1fc8ce7009b46bb959f9bda0d.png

They are all just letters that represent variables, there is no inherent reason for choosing them. They could have just as easily been A, σ, y or anything else.

cougar337
02-24-2009, 11:56 AM
Thank you very much for an awesome class!! I'll have to postpone my exam and take it a little later (thanks for the link Nathaniel) but I feel pretty confident about taking the test now. I learned alot in the 2 days I was in the class and it was easy to learn with the practical applications everyone gave.

I can't wait to get my license and start looking at set ups!!:woot:

treerootCO
03-02-2009, 09:59 AM
I have another person that would like to take the test tonight. Let me know if there is anything special you need from them. Two forms of ID (photo), SSN, and $15 is all I am aware of.

RicardoJM
03-02-2009, 10:42 AM
I have another person that would like to take the test tonight. Let me know if there is anything special you need from them. Two forms of ID (photo), SSN, and $15 is all I am aware of.

That is what is required. Also, please make sure they are aware that we are only able to offer the Technician level exam. At most other Test sessions, the examiners are qualified to offer the General and Extra exams, and many times people will pass the Technicians exam and then try the General - they get the most bang out of their $15 testing fee. Just don't want someone to come in expecting something that we can not delvier. :thumb: