Wednesday, June 30, 2010

Lesson 20: Technician Class Exam Prep T6B

This is the 20th lesson in the Technician Class Exam preparation course.  This lesson covers the T6B questions from the exam question pool dealing with semiconductors.  This lesson primarily focuses on the functions of diodes and transistors.  This subject can get pretty deep, but I tried to give you enough of a knowledge base in the video to deal with the questions.

Some of the items you will need to remember.

-Diodes allow current to flow in only one direction.
-The leads on a diode are called an anode (+) and a cathode (-).  The cathode is identified with a stripe.
-Transistors are capable of using a voltage or current signal to control current flow and can act as amplifiers or switches.
-A Bipolar junction transistor has three leads.  They are the base, emitter, and collector.
-A field effect transistor, or FET, has three leads as well.  They are the gate, source, and drain.

If you have all this you should be fine with this section.  Explanations of semiconductors on the internet tends to be a bit complex.  If you are looking for more information about semiconductors, or electronics in general, I recommend the book Understanding Basic Electronics published by the ARRL.  This gives down to earth and simple explanations of some fairly complex electronics subjects.  This book does not presume you have any previous knowledge of electronics and builds from the ground up.  A great book!

Until next time and lesson 21...

73,
Andy
KE4GKP


Tuesday, June 29, 2010

Lesson 19: Technician Class Exam Prep T6A

Again, welcome back!  Here is lesson 19 which goes over electronic components from the T6A section of the exam question pool.  Even though you don't need to learn the schematic symbols of the various components for this lesson, I threw some in there anyway.  There are other sections where you will need to know a schematic symbol or two and I figured it would be easier if some of it were review at that point.  This lesson is one of the funner ones. 

Be sure to take the quiz in the video!  It really does help if you go through the quiz and try to answer the questions correctly.  This repetition helps build memory and really increases your score when you finally take the exam...I promise.

If you have any questions, comments, or suggestions, I welcome it all.  Until the next lesson...

73,
Andy
KE4GKP


Monday, June 28, 2010

Lesson 18: Technician Class Exam Prep T5D

Welcome back!  Here is lesson 18 which covers the T5D questions from the exam question pool and is entirely devoted to Ohm's law.  If you haven't memorized or know how to use Ohm's law yet, you will after this lesson.  Ohm's law basically states that voltage, current, and resistance in a circuit are all related.  The formula is E=IR where E is voltage in volts, I is current in amperes, and R is resistance in ohms.  From the word problems on the exam, you solve the equation for the variable you are looking for and just substitute in the numbers.  There is a decision circle which helps solve for each variable quickly.  It looks like this:
                                                
To solve for voltage, current, or resistance, you just cover the letter you are looking for and what remains uncovered is what you need to calculate.  For instance, if you are looking for resistance, you cover the 'R' in the circle and what you are left with is E/I.  So divide E (volts) by I (amperes) and it will give you the resistance in ohms.  Simple?

If you have any questions, comments or suggestions, please feel free to leave them in the comments box.  Until the next installment...

73,
Andy
KE4GKP



Sunday, June 27, 2010

Lesson 17: Technician Class Exam Prep T5C

Hello again!  Lesson 17 is one of the funner lessons in my opinion.  In this lesson we get started covering some basic electronic principles and components.  There are a few basic units and a formula you need to memorize for this section.

The basic unit of capacitance is the farad.
The basic unit of inductance is the henry.
The basic unit of frequency is Hertz.

And you need to be able to find the power in a DC circuit when you are given the current (amperes) and voltage,  That formula is:

P=IE  Where P is power in watts, I is the current in amperes, and E is the voltage in volts.

And that's about it.  As always, I welcome your questions, comments, or suggestions...especially the suggestions as I am trying to build this site into a useful resource.  Thanks!

73,
Andy
KE4GKP


Saturday, June 26, 2010

Lesson 16: Technician Class Exam Prep

Here is lesson 16.  This lesson may prove to be the toughest one yet in preparing for the Technician Class exam.  This lesson covers the T5B questions dealing with metric conversions and calculating decibels (dB).  Don't worry I've broken down what you need to know.  There is a metric conversion chart in the links section, but for the purposes of the exam I will lay down what you need to memorize.

Keep in mind that the prefix in a metric unit (kilo, mega, pico, etc) describes the size of a particular measurement to the standard unit of measure.  So if the standard unit of measure is watts, a kilowatt is 1000 watts.  These metric prefixes help us deal with really big and really small numbers.  Here are the ones you need to memorize:

Pico = 1/1,000,000,000,000 (1 trillionth) of the standard unit (Hz, Amperes, Volts, etc.)
Micro = 1/1,000,000 of the standard unit (Hz, Amperes, Volts, etc.)
Milli = 1/1000 of the standard unit (Hz, Amperes, Volts, etc.)
Kilo = 1000 of the standard unit (Hz, Amperes, Volts, etc.)
Mega = 1,000,000 of the standard unit (Hz, Amperes, Volts, etc.)

To find how many kHz go into a MHz, one way to find the answer is to break the number down into Hz.  A kHz is 1000 Hz.  a MHz is 1,000,000 Hz.  So to find out how many kHz go into a MHz, all you do is divide the bigger unit into the smaller unit.  1,000,000/1000 = 1000 so 1 MHz is equal to 1000 kHz.

To find how many MHz 3525 kHz is, you can break the numbers down into the base unit (Hz) as well.  So 3525 kHz is equal to 3,525,000 Hz and a MHz is equal to 1,000,000 Hz.  Divide 3,525,000 by 1,000,000 and you get 3.525 MHz.  It's a lot easier if you've ever been taught to multiply and divide by powers of 10.  If you remember, the conversion chart in the links section has the powers of 10 listed.

The other piece of memorization you need to do is the formula for calculating decibels (dB).  Bels are often used to calculate the amount of change in noise or power.  Decibels are the units used most often.  A decibel is 1/10th of a Bel.  The way this is used is it calculates the amount of change from one power or noise level to another.  Logarithms are used in the formula so it would be wise to find yourself a good scientific calculator.  On the exam, the questions deal with changes in power.

The formula you need to memorize is:

dB = 10log(P1/P0
Where P0 is the reference power (where you're starting from) and P1 is the power being compared to the reference power (where you are ending).  So if you were to calculate the change in dB from an increase in power from 3 watts to 10 watts, P0 would be the 3 Watts (where you're starting) and P1 would be 10 Watts (where you're ending).  Substitute these numbers into the formula and that's it.  It's also important to note that if the change in power is a decrease (10 watts to 3 watts, for example) the answer on the calculator will be a negative number.  Since we are dealing with the amount of change, the answer will always be positive.  It is like calculating distance.  If you drove 20 miles and them backtracked 5 miles, the total distance traveled is 25 miles.  Just because you backtracked doesn't mean those 5 miles are subtracted from the 20 miles.  Change is the same way.  A decrease in power only means the change is happening down vice up.  Clear as mud?

If you have any questions, comments, or suggestions (there might be a few in this one...I am a rotten math teacher) please leave them in the comments box.  Until the next lesson...

73,
Andy
KE4GKP



Friday, June 25, 2010

Lesson 15: Technician Class Exam Prep T5A

And once again, here is the latest lesson installment to prepare you for the Technician Class Amateur Radio exam.  In this lesson, we go over the T5A section of the question pool which cover basic electrical principles.  There are a few basics which you will need to memorize if you (like me) have erased most of your high school physics class out of your memory.  They are:

-Current is measured in Amperes.
-The rate at which electrical energy is used is called Power.
-Electrical power is measured in Watts.
-Electromotive Force (EMF) is also known as Voltage and is measured in Volts.

Until the next installment...

73,
Andy
KE4GKP


Thursday, June 24, 2010

Lesson 14: Technician Class Exam Prep T4B

Here is lesson 14 of the Technician Class Amateur Radio Exam course.  This lesson covers the T4B questions from the exam question pool dealing with operating controls.  One of the things I recommended for this lesson is to go to the newsstand, or order online, a copy of an Amateur Radio magazine like QST (published by the ARRL) or CQ : Radio Amateurs Journal.  Look through the magazine, especially the ads for the various new transceivers.  Take particular note of what features these transceivers have.  What type of memory, squelch, gain control, etc.  Also, it wouldn't hurt to read through some of the equipment reviews.  This will give you a good idea what this section of the exam is talking about, plus it gives you an excuse to buy a Ham Radio magazine.  Until lesson 15...

73,
Andy
KE4GKP


Wednesday, June 23, 2010

Lesson 13: Technician Class Exam Prep T4A

Welcome back!  In lesson 13 we go over the T4A section of the question pool dealing with Station Setup.  This is a relatively easy lesson and should give your brain a rest for a bit.  In this lesson I talk about a data mode called PSK 31.  PSK 31 stands for Phase Shift Keying 31 Baud and is one of the easiest data modes to get started.  PSK 31 is resistant to interference and solid signals can be received where voice and most other means of data communication fail.  It requires low power and a very simple antenna to get great signals.  I've added a link if you are interested.

Until next time...

73,
Andy
KE4GKP


Tuesday, June 22, 2010

Lesson 12: Technician Class Exam Prep T3C

Hello once again!  Here is the latest addition, Lesson 12, to the Technician Class Exam Course.  This lesson covers the T3C section of the question pool.  This section deals primarily with radio propagation.  This is a big deal if you are looking for those DX, or distant, contacts.  One of the subjects that wasn't covered in too much detail in the questions is the D, E, and F layers of the ionosphere.  These are the key layers when we are talking radio waves traveling great distances.  Depending on the band and the time of day, you can get all sorts of great contacts by bouncing radio signals off the ionosphere.  I added a link in case you were looking for more information.  As always, if you have any questions comments or suggestions please leave them in the comments box.  Until lesson 13...

73,
Andy
KE4GKP


Monday, June 21, 2010

Lesson 11: Technician Class Exam Prep T3B

Hello once again! Here is Lesson 11 of the Technician Class Exam Course.  In this lesson we cover the T3B questions from the exam question pool concentrating on Radio and Electromagnetic Wave Properties.  There is a good amount of memorization for this section.  I have broken down what I think might be tricky to remember here to help focus your memorization skills.

The speed of light = 300,000,000 meters per second

Wavelength (meters)=300/frequency in MHz

Frequency limits of the HF Spectrum 3-30MHz; VHF Spectrum 30-300 MHz; and UHF Spectrum 300-3000 MHz.

If you have any questions, comments, or suggestions please leave them in the comments box.  Until lesson 12...

73,
Andy
KE4GKP


Sunday, June 20, 2010

Lesson 10: Technician Class Exam Prep T3A

Hello again!  This is lesson 10 which goes over the T3A questions from the Technician Class exam question pool and covers Radio Wave Characteristics.  Now we are starting to get into the real meat of Ham Radio!  The challenge of Amateur Radio is to figure out how to manipulate electromagnetic waves to carry radio signals when, how, and where you want them.  This brings either great joy or despair to every Ham operator.  I hope you enjoy the video.  As always, fell free to leave any questions, comments, or suggestions in the comments box.

73,
Andy
KE4GKP


Saturday, June 19, 2010

Lesson 9: Technician Class Exam Prep T2C

Welcome back!  Here is the 9th Lesson in the Technician Class Amateur Radio license prep course.  This lesson deals with the T2C section of the exam question pool which covers Public Service.  In this video I talk a little about RACES and ARES.  These are both excellent groups to be a part of if you are interested in emergency communications.  They offer excellent training and provide you a chance to give back to the community.  Also, once you're lecensed, the ARRL has an excellent set of emergency communication courses to help get you proficient in how the process works, hierarchy, etc.  Until lesson 10...

73,
Andy
KE4GKP


Friday, June 18, 2010

Lesson 8: Technician Class Exam Prep T2B

Hello once again!  Here is Lesson 8 of the Technician Class Exam Prep Course covering the T2B questions from the question pool.  This lesson covers questions dealing with VHF/UHF operating practices.  There are some tricky questions that deal with FM signals, deviation, amplitude, and bandwidth in this one.  Unless you want to go deep in to Frequency Modulation, I recommend just memorizing the answers to the two questions.  I provided a few comparisons (though probably poor ones) to help you remember the answers.  You will have plenty of oportunity to go into detail when the issues come up after you get your license.  However, I am providing a link if you want to go into more detail now.  As always, I am happy to receive any questions, comments, or suggestions.  Please leave them in the comments box below.

73,
Andy
KE4GKP




Thursday, June 17, 2010

Lesson 7: Technician Class Exam Prep T2A

Hello all!  This is lesson 7 of the Technician Class license exam course dealing with the T2A questions from the exam question pool covering Operating Procedures.  Even though you may only expect one question from the T2A section on the exam, this is important stuff to know for general Ham practice.  Please feel free to leave any questions, comments, or suggestions in the comments box.  Until lesson 8...

73,
Andy
KE4GKP


Wednesday, June 16, 2010

Lesson 6: Technician Class Exam Prep T1F

Hello again! This is the 6th lesson to get you prepared for the Amateur Radio Technician Class exam.  In this lesson we cover the T1F questions from the exam question pool which is the last of the T1 sub-element so you've reached the first milestone!  The subjects covered are station identification and operation standards to include special operations for repeaters and auxiliary stations, third party communications, club stations, station security, and FCC inspections.  Because this video went a little long it is broken into two parts.

One of the subjects that was not covered in too much detail in the question pool but I think is important is Third Party Communications.  There are two slightly different aspects to third party communications.  The first is the passing of messages from a non-licensed individual (third party) over the Amateur bands to another non-licensed individual.  With in the United States, this is fine as long as the persons operating the transmitters are licensed U.S. Amateurs and the message does not violate any FCC rules.  Third party communication is done a great deal in emergency communications and disaster relief.  From an international point of view, third party traffic is acceptable only if the foreign government where the message is being sent or received allows third party message traffic. In the second aspect, Amateurs may allow a third party to send the information themselves over the Amateur bands.  This can only be done under the direct supervision of a licensed Amateur who acts as the control operator.  The control operator is responsible to ensure the third party sending the message remains in compliance with FCC rules and regulations.   Clear as mud?

As always, if you have any comments. questions, or suggestions please leave them in the comment box.  Until next time...

73,
Andy
KE4GKP





Tuesday, June 15, 2010

Lesson 5: Technician Class Exam T1E

We're well on our way!  This is the 5th lesson in the Technician Class exam course to help you get your Technician Class Amateur Radio license.  In this lesson the T1E questions from the exam question pool are covered.  The subjects include station control and type of control.  As always, please leave any questions, suggestions, or comments you may have in the comments box below.  Until the next lesson...

73,
Andy
KE4GKP


Monday, June 14, 2010

Lesson 4: Technician Class Exam T1D

 Here is the latest lesson on the way to taking the Technician Class Amateur Radio exam.  As always, if you have any questions, please leave them in the comments box and I will be happy to get back to you.  Also, if you are interested in exploring any of the subjects in more detail than this page and the links can provide, I highly recommend getting a copy of The ARRL Handbook for Radio Communications.  It has everything you need to know or ever want to know about Ham Radio.  It is updated annually and is an essential piece of information for any Amateur operator.  Until the next lesson...

73,
Andy
KE4GKP


Sunday, June 13, 2010

Technician Exam License Prep: Lesson 3

Here is the latest installment of the Technician Exam License series.  Please feel free to leave any comments or questions in the comments section.  I'll be happy to get back with you.

73,
Andy
KE4GKP


Saturday, June 12, 2010

Technician Class License Exam: Lesson 2

Here are some pieces of the video that I thought would be helpful to see again:

First, you can find the mode and frequency chart published by the American Radio Relay League (ARRL) on the links window.  It breaks down everything for all licensed U.S. Amateurs.  Second, the frequencies I suggested in the video that you memorize are listed below:

6M     50-54 MHz
All modes anywhere except for 50-50.1 MHz which is CW only

2M     144-148 MHz
All modes anywhere except for 144-144.1 MHz which is CW only

1.25M     219-220 MHz and 222-225 MHz
219-220 MHZ is fixed digital message forwarding system only
All modes for 222-225 MHz

70cm     420-450 MHz
All modes anywhere

23cm 1240-1300 MHz
All modes anywhere
 
There are a few things to keep in mind concerning this list.  Even though the FCC won't get upset if you use any authorized mode anywhere it is authorized, a lot of Hams will.  When transmitting, it is best to adhear to the band plan agreed upon by most amateur operators.  I have a link to the band plan in the links window.  Also, the above frequencies are not all the frequencies authorized for a Technician Class operator.  These are just the bands, frequencies, and modes you need to know to pass the exam.  I'm trying to keep it easy.  I've also provided a link to information regarding the various modes.  If you have any questions, I'd try there first.
 
I hope these videos are working out for you.  Remeber, these videos are designed to get you past the exam.  Actually operating a Ham station is not a closed book exam.  You can have whatever you need to know right in front of you when you are actually transmitting.  Don't sweat it.
 
If you have any questions, please leave them in the comments box.

Thanks and 73!
Andy
KE4GKP


Friday, June 11, 2010

Tech License Intro and Lesson 1


This is the first video in a series of probably about 35 preparing for the Technician Class exam.  I had to push the time to get the video within YouTube parameters so if there are any questions, please leave them in a post and I'll get right to them.  This was also my first adventure into a video podcast so please, bare with me.



Ham Radio,It's Fantastic!

I really enjoy Ham radio. I like building my own equipment, looking for new contacts, and collecting the QSL cards that eventually come from those big, hard to find contacts. It is relaxing and relatively exciting all at the same time. Sort of like an electronic form of fishing. In fact at it's fundamentals, it is almost exactly like fishing. You throw your line (signal) into the water and see who bites. There are more adventurist sides of Amateur Radio as well. Ham Radio introduced me to storm chasing and satellite communication.  I talked to Bosnian Hams reporting war updates.  I talked to space shuttle astronauts.  And once almost was able to talk to the King of Jordan.
Unfortunately, I've strayed a bit from the hobby over the last few years. I made a few attempts to get going strong again but something always got in the way, usually work. I've decided to get going again despite all my other commitments and am going to use this blog as a tool to stick to it.
One of the things I've always had a problem with Ham radio is a lot of the Hams out there are not very good teachers. I got my license pretty much by memorizing the question pool posted by the FCC without any explanation. I can tell you what the answers are but I don't understand a lot about the "how". It's also intimidating as all get out to get out there and get transmitting without worrying about messing up. I am going to address that here and maybe fill in the gaps that I found when I first got started. I'm going to get back to the basics in my fresh start and do my best to figure it out. Hopefully I'll get back into the swing of things and find that Zen once again.