Technician Class Series – Your First Radio

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Hello everybody and welcome back to my blog! Today we are going to continue our series on the Technician Class License Question Pool! Today we will be talking about your first radio.

As always, the correct answers will be in bold. I also recommend that you only read the correct answers when studying for your test. If you do this, when you take your test and you see a question, there will be a better chance that the correct answer will jump out at you easier. Some say that this approach is kind of like cheating, but the way that I see it, you will always be learning something in this hobby and you don’t have to know everything there is to know about the hobby to get your license.

If you would like to purchase a copy of the Technician Class study book that this series is:

Let’s move on to the good stuff, shall we?


T7A07 What is meant by term “PTT”?

A. Pre-transmission tuning to reduce transmitter harmonic emission

B. Precise tone transmissions used to limit repeater access to only certain signals

C. A primary transformer tuner use to match antennas

D. The push to talk function which switches between receive and transmit

PTT = Push-To-Talk! This is the button that you have to press in order for your words to be transmitted by the radio over the airwaves to who ever you might be talking to. Now-a-days it is just one button that you have to press, but if you were to talk to any of the “old timers’, those that have had their license for 50+ years, they can tell you stories about radios that you had to flip several switches to talk. The PTT button effectively turns off your receiver and turns on your transmitter and visa versa when you left off the PTT.

 

T4B04 What is a way to enable quick access to a favorite frequency on your transceiver?

A. Enable the CTCSS tones

B. Store the frequency in a memory channel

C. Disable the CTCSS tones

D. Use the scan mode to select the desired frequency

My very first radio had 25 memory channels on it I believe. It was a Radio Shack HTX-202. That radio was a brick compared to the radios that are on the market today. Here is a picture of what it looked like:HTX-202 HT

 

 

T9A04 What is a disadvantage of the “rubber duck” antenna supplied with most handheld radio transceivers?

A. It does not transmit or receive as effectively as a full-sized antenna

B. It transmits a circularly polarized signal

C. If the rubber end cap is lost it will unravel very quickly

D. All of these choices are correct

The factory supplied “Rubber duck” antenna is the bare minimum that you need to get a signal out. It is basically about as good a dummy load. It doesn’t have any gain to it. If you are talking to a friend a mile away and you are both outside, then it will work. If you are trying to reach a repeater five miles away or more, you can pretty much forget it. You can buy an after market “rubber duck” antenna that will have some gain to it though. So when you buy your hand held radio, you might also consider buying one of the after market antennas as well, and if you are using it in your vehicle, it wouldn’t be a bad idea to buy a mag mount antenna as well, just make sure that you buy the correct adapters to hook it to your hand held.

T9A07 What is a good reason not to use a “rubber duck” antenna inside your car?

A. Signals can be significantly weaker than when it is outside of the vehicle

B. It might cause your radio to overheat

C. The SWR might decrease, decreasing the signal strength

D. All of these choices are correct

When you are inside your vehicle with all that metal around you, your signal will be significantly weaker that if you were standing around outside of it.

 

T7A10 What device increases the low-power output from a handheld transceiver?

A. A voltage divider

B. An RF power amplifier

C. An impedance network

D. All of these choices are correct

In this question, the easiest was to remember it is to look for the keyword, “power”. There is only one options that says anything about power. In practice though, an Amplifier is the last thing on your list that you should buy when you put a HT in your car for mobile use. The first thing that you need to look at is an external antenna. Most of the time that external antenna will do everything you need without having to increase the power. With that being said and me living in an area where I’m not always with a short distance from a repeater, there are times when more than the five watts, that an HT put out, would be useful. Amplifier will normally take a 5 watt signal and turn it into 50-100 watts output. However, they can be kind of spendy so why not save a little extra money and just buy a mobile unit for your car.

 

T8A04 Which type of modulation is most commonly used for VHF and UHF voice repeaters?

A. AM

B. SSB

C. PSK

D. FM

AM, SSB and PSK are generally for HF frequencies. There are a few SSB areas in the VHF/UHF bands but for a repeater use, it is a very slim chance that you will ever find one that uses anything but FM or Frequency Modulation.

 

T8A09 What is the approximate bandwidth of a VHF repeater FM phone signal?

A. Less than 500 Hz

B. About 150 kHz

C. Between 10 and 15 kHz

D. Between 50 and 125 kHz

Most FM signals on the VHF frequencies range between 10-15kHz. If your equipment is properly tuned, it will be right around 10kHz which is the norm.

 

T2B05 What determines the amount of deviation of an FM (as opposed to PM) signal?

A. Both the frequency and amplitude of the modulating signal

B. The frequency of the modulating signal

C. The amplitude of the modulating signal

D. The relative phase of the modulating signal and the carrier

How much deviation on an FM signal is dependent on the amplitude of your signal. The loader you talking into your microphone, the greater the amplitude, therefore the higher the deviation.

 

T2B06 What happens when the deviation of an FM transmitter is increased?

A. Its signal occupies more bandwidth

B. Its output power increases

C. Its output power and bandwidth increases

D. Asymmetric modulation occurs

On FM, when the deviation increases so does the bandwidth required to transmit the signal. With recent changes to the digital era, many repeaters are being forced into narrow bandwidth instead of the wide bandwidth that FM use to have. Instead of the normal 10 kHz, there is only 5 kHz to use. So if your radio isn’t tuned to use the narrow bandwidth, the repeater wont properly pass your transmitted signal, unless you speak softly to minimize the bandwidth you are using.

 

T8A02 What type of modulation is most commonly used for VHF packet radio transmissions?

A. FM

B. SSB

C. AM

D. Spread Spectrum

The majority of the VHF and UHF frequencies us FM. There is a small area in the 6m, 2m, 1.25m and 23cm bands that are designated SSB along with the majority of the 33cm band, but for the most part its going to be FM.

 

T4A02 How might a computer be used as part of an amateur radio station?

A. For logging contacts and contact information

B. For sending and/or receiving CW

C. For generating and decoding digital signals

D. All of these choices are correct

With the digital age moving us along so fast, if you were ask this question 10 years ago, the answer would be a lot different. Now-a-days there are computer controlled radios, radios that are all software driven, APRS, echolink, packet(a fastly dying mode), RTTY, FSK, even CW can be received and set via a computer. Technology has moved so far and so fast over the last 10-15 years that it’s hard to keep up with it.

 


That about wraps it up for this week. I hope that yall are continuing to find this series helpful, not only for those new hams and soon to be hams, but also those that have been hams for a while. This hobby is ever changing and ever evolving so you will be learning new things all the time.

If you haven’t already, please subscribe to my blog either on email or RSS feed, like me on Facebook and follow me on Twitter, Google+ and LinkedIn. I want to thank you for coming and reading my blog and I hope that you will continue to come back in the future. Until next time…

73 de Curtis, K5CLM

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