© Alex Wulff 2019
A. WulffBeginning Radio Communicationshttps://doi.org/10.1007/978-1-4842-5302-1_8

8. Handheld Transceivers and Repeaters

Alex Wulff1 
(1)
Cambridge, MA, USA
 

This chapter is meant to introduce you to some of the technology that powers the world of amateur radio. We’ll first cover the handheld transceiver (HT), a small radio that allows you to get on the air quickly. Even if you don’t have your license, you can still participate in this chapter. Just know that you cannot transmit anything until you’re licensed.

Your Handheld Transceiver

The handheld transceiver we’ll be using throughout this book is the BaoFeng UV-5R (shown in Figure 8-1). There are many variants of this radio, and they all have basically the same features. BaoFeng is a Chinese company that was the first to really introduce low-cost HTs to the masses. These are oftentimes the first radios that a ham will purchase, and they usually work for years without any problems. Low-cost BaoFeng radios are by no means perfect, but they’re a great way to get on the air for new hams. They feature comparable specifications to mid-range transceivers that cost $100+. If you haven’t picked one up yet, go to the “Materials” section of this book and buy one from the link provided. If you already have a different handheld transceiver, you should still be able to follow along.
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Figure 8-1

The BaoFeng BF-F8+, which is almost identical to the UV-5R. Other similar variants of this radio look exactly the same, except for the text at the bottom of the radio indicating the model

A common criticism of these radios is that they enable unlicensed individuals to utilize amateur radio frequencies, as the radios are cheap and somewhat easy to use. It’s not uncommon for groups of individuals to pick up a set of these radios and use them to communicate while hiking, skiing, and more. But this is illegal. If you do not have proper licensing, you cannot use the transmit functionality of these radios (or any that utilize amateur frequencies). It is perfectly legal, however, to listen to whatever you want using your HT without a license. If you haven’t taken the licensing test yet, you can still participate in the exercises in this chapter by listening instead of both transmitting and listening.

You could be forgiven for confusing your HT with a generic walkie-talkie such as the ones in Figure 8-2. At their cores, both devices have a very similar function: transmit/receive voice information over radio waves. Where walkie-talkies use opaquely defined “channels” to obscure the real transmit/receive frequency, HTs allow the user to directly set the transmit and receive frequency to within 5 kHz steps. Most walkie-talkies operate in a special portion of the 2 m band reserved for walkie-talkies, while your HT can transmit and receive on amateur radio 2 m and 70 cm bands.
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Figure 8-2

A selection of walkie-talkies, each of which looks very similar to a typical handheld transceiver

Another difference is transmit power. Most walkie-talkies output around 0.5 W or 1 W, which allows for communications at a maximum of a few miles. Your BaoFeng UV-5R can output up to 5 W, increasing the maximum range to a few tens of miles with a good antenna. In proper conditions, individuals have made contacts using 5 W and the stock antenna from over 100 miles away. This is most often only possible from high elevations free of obstructions in the path.

Another cool feature of HTs is your ability to use them with all kinds of antennas. Walkie-talkies have an antenna attached to the device, but all HTs offer an interconnect that allows you to disconnect the stock antenna and attach whatever you want. The stock antenna on BaoFengs is notoriously bad, so many opt to purchase better-matched “rubber ducky” antennas of the same form factor. You can also use an HT with a more elaborate antenna setup, such as the optional log-periodic antenna in the “Materials” section. This enables extremely long-distance contacts such as with satellites. A handheld transceiver with a special rollable antenna is shown in Figure 8-3. Lastly, HTs have many software-configurable features that make them useful to hams. We will explore many of these in the following sections!
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Figure 8-3

A handheld transceiver connected to a “slim jim” antenna. These antennas can be rolled up when not in use, and provide much better gain at VHF and UHF than the stock antenna

Using Your Handheld Transceiver

The first thing you should do when you get your radio is place it in its provided charging cradle. The radio and cradle are shown in Figure 8-4. The battery life on these devices is quite good; with infrequent transmissions, you can expect it to last for an entire day. Keep it charging until the light on the front of the cradle turns green, which indicates that it’s done charging.
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Figure 8-4

A BaoFeng UV-5R in its charging cradle

Next, remove your radio from the charging cradle and turn it on by twisting the knob at the top. In addition to powering on/off the radio, this knob controls the output volume of the speaker. Your radio should greet you with a series of beeps, and the display should light up. We’ll first start by identifying all the buttons on the radio and their function.
  • Pressing the red button on the left side (labelled “call”) will switch the radio to FM-radio-receive mode. Any incoming signals on the amateur frequency the radio is set to will automatically silence the FM radio. Holding the call button will activate alarm mode, which you should avoid doing.

  • The button below call is PTT, or push-to-talk. This will activate the transmit function of the radio and transmit your voice! If you’re unlicensed, pressing this button is illegal.

  • The button below PTT is used to turn on the flashlight or open the squelch (discussed later).

  • Next, looking at the face of the radio you should see a button labelled “VFO/MR.” This allows you to configure your radio between stored channel mode and frequency mode. In frequency mode, you can manually set the transmit and receive frequency of the radio. In channel mode, you can cycle between preprogrammed channels.

  • The “A/B” button allows you to switch between the frequencies or channels on the upper and lower portions of the display.

  • The “menu” button allows you to configure the settings of your radio. In the menu screen, you can cycle between different options by pressing the up and down arrow keys, or you can type the number of a given option to access it quickly. Once you’ve reached the desired setting, you can access it by again pressing the menu button, and then you can change the setting with the number keys or arrow keys. Pressing the menu button again will save your selection—you need to do this after you change any setting, as they do not save automatically. You can press the “exit” button to return to normal operation.

  • While in frequency mode, you can enter the frequency at which you wish to transmit and receive through the number keys. In channel mode, entering a number with the number keys will take you to that channel.

Don’t worry if the interface seems confusing at first—it is confusing, but you’ll learn it quickly if you use your radio frequently. Table 8-1 lists some common menu options that you’ll likely need to use at some point.
Table 8-1

Useful BaoFeng menu options.

Number

Name

Description

0

SQL

“Squelch” is essentially a threshold that the received signal must surpass in order to be output to the speaker. This saves you from constantly hearing noise.

2

TXP

This setting is the transmit power. You can change this between LOW (1 W) or HIGH (5 W).

13

T-CTCS

Transmit-continuous tone coded squelch is explained more in the following, but you’ll likely need to modify this in order to communicate through repeaters.

25

SFT-D

Shift direction. Again, this is explained in the following, but you will likely need to modify this setting at some point.

26

OFFSET

This is another setting that you’ll need to communicate with repeaters which is also explained in the following.

40

RESET

If you mess something up, you can quickly reset your radio with this option.

Repeaters

Now that you’re familiar with how your radio operates, you can use it to do interesting things! An integral part of HT-based amateur radio communications is repeaters. Repeaters are devices that accept incoming voice signals and rebroadcast them at a much higher power at a slightly different frequency. This enables a simple handheld transceiver to communicate with devices across a large swath of area, generally many tens of miles in diameter. The repeater may not provide much benefit for transmissions close to you, but it can effectively double the maximum range of transmissions to distant handheld transceivers. Even if your device cannot reach a given receiver, you can often still hear transmissions from it. Some repeaters have coverage maps that show the maximum distance from which an individual can typically hear transmissions. Figure 8-5 is an example of a coverage map. This map does not show the coverage of a repeater, but rather a weather radio station operated by NOAA. This station transmits at 1 kW, and is located in New York City. Coverage maps are generally computer simulated based on the geography of the region.
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Figure 8-5

A typical coverage map, with coverage shown in white

Repeaters are most often tower-based devices. The actual signal processing hardware is quite compact, but to get a decent amount of coverage, one must mount antennas for the system atop a tower. Repeaters can be placed on mountaintops or hills, and share the same tower as other communications equipment (see Figure 8-6). Repeaters are managed by individuals or amateur radio clubs in that region.
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Figure 8-6

A typical telecommunications tower—one of the monopole antennas here could very likely be utilized as an amateur radio repeater

Your HT is well equipped to communicate with repeaters. There are plenty of 70 cm and 2 m repeaters, both of which you can transmit to and receive from using your HT. You generally need to know three things to communicate with a repeater: frequency, offset, and private line (PL) tone .

Repeater Frequency

The listed frequency for a repeater is the frequency at which the repeater transmits signals. If you just want to listen to transmissions from the repeater, you can simply tune your radio to this frequency and be done. If you want to transmit through a repeater, you’ll need more information. As mentioned before, repeaters transmit at a different frequency than they receive. This helps prevent interference from many hams trying to talk at the same time.

Repeater Offset

The repeater offset is the distance, in frequency, between the transmit frequency and the receive frequency. Almost all 2 m repeaters utilize a 600 kHz offset, and almost all 70 cm repeaters utilize a 5 MHz offset. You need to know the offset direction for a given repeater, which describes the direction in which the offset is applied. For example, a repeater operating at 147.000 MHz (which is in the 2 m band) with a positive offset will transmit signals at 147.000 MHz and accept incoming signals at 147.600 MHz.

Repeaters are generally listed something like “147.000+”—the frequency of the repeater is the number, and then the offset direction is either a “+” or a “-” to indicate a positive or negative offset. You can set the offset direction in your radio by going to menu setting 25, which is also listed in Table 8-1. When active, a plus or a minus sign will appear on your display, and when transmitting the displayed frequency will change to the base frequency plus or minus the offset. This is shown in Figure 8-7. Ensure that you know when this setting is operational, as it can cause transmissions to something other than a repeater to fail if the receiving device is not configured to use an offset.
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Figure 8-7

The screen of an HT when a positive offset is applied. Notice the “+” located at the top

PL Tone

Most repeaters will not accept incoming transmissions that are not accompanied by a special subaudible tone. This is mainly to prevent unintended activation of the repeater by noise or spurious signals. This tone is often called a PL (“private line”) tone or a CTCSS (“continuous tone-coded squelch system”) tone. These are the same thing. As described before, squelch is a way to prevent your radio from constantly being activated by noise. CTCSS is merely a smarter way to activate a repeater or a radio. Repeaters have specific PL tones that will activate them, and they will not activate if they don’t receive this specific tone.

PL tones are generally in the range of 50 Hz–150 Hz, which are considered to be subaudible. PL tones are configurable in your radio using menu option 13. A full listing for a repeater will generally appear as “147.000+ PL 71.9.” You already know what the first part of this indicates, and the number after “PL” indicates the PL tone (measured in Hz). Leaving the PL tone on for transmissions other than to a device configured to use them is harmless. The tone is subaudible, so the receiving device will not even notice that it’s there unless specifically designed to listen for a PL tone. Much like with offsets, your HT will indicate if a PL tone is active. The tone screen is shown in Figure 8-8, and some radios indicate that a tone is active on the main screen.
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Figure 8-8

The PL tone menu screen

Finding a Repeater

You now know the basics of how repeaters operate, but how can you actually obtain information about repeaters in your area? As usual, the answer is the Internet. Searching “amateur radio repeaters in ____,” with the line replaced with the name of the closest city to you, will generally provide a comprehensive list. You’ll be surprised at just how many repeaters there are in your area—there’s a large community of hams all across the globe that dedicate a significant amount of time building repeater networks. You can also purchase a book called a Repeater Directory which lists repeaters by city or state.

Some repeaters form a linked network. Signals picked up by one repeater will be broadcast by all other repeaters linked to it, allowing for extremely long-distance communications. The fact that a repeater is linked to another is normally indicated in the repeater listing. You’ll generally find that you can reach repeaters a maximum of 15 miles away with 5 W, or the highest transmit power of your radio. A general rule of thumb is if you can see a repeater, you can probably reach it.

Some repeaters are part of the EchoLink system—EchoLink allows you to connect to any repeater that’s a part of its system via the Internet. You can both monitor transmissions coming into the repeater and send your voice out over the repeater with no radio required. EchoLink is a great way to monitor repeaters if you don’t have a radio on you, but you’ll need to have an FCC callsign to sign up. Repeaters that are part of the EchoLink system are given a node ID that you can utilize to connect to them.

Making a Repeater Contact

Hams operating other voice modes and bands than FM and VHF/UHF oftentimes utilize calling frequencies to initiate a contact. A calling frequency is a predetermined frequency where one would advertise a desire to initiate a contact. Since these other bands propagate farther and are usually operated with higher-power equipment, it’s easy to find a contact this way—however, this is unsuitable for handheld transceivers, as they operate across a very limited geographical range.

Local amateur radio operators with HTs will instead rely on repeaters as common frequencies at which to make a contact. Many individuals leave their radios on and constantly tuned to repeater frequencies to pick up such contacts if they occur. If you’re lucky, someone is listening to a repeater around you right now!

Due to repeaters’ function as local “gathering places” for hams, many new hams make their first contacts through a repeater. Unless you’re in a densely populated area, you may never find hams talking on frequencies other than those used by a repeater with your handheld transceiver. Repeaters have the added benefit of being geographically optimized for an area. In a valley, transmissions will generally be blocked by the hills or mountains on either side. Repeaters at the top of the hill can rebroadcast your signal out of the valley and across the surrounding area.

Let’s now set up your radio. Configure your radio with the correct frequency, offset, and PL tone for a repeater around you. Once you think everything is set up correctly, you’re ready to go! To initiate contact on a repeater, one usually says his/her callsign followed by the word “listening.” This indicates to other hams that may be on the repeater that you are monitoring the repeater and looking for a contact. Before doing this, ensure that the repeater is not currently in use by listening for a minute. If a conversation is currently underway, you can break in by announcing your callsign and your name in the gap between exchanges.

Many repeaters are configured with a courtesy tone to show you that your transmissions are going through and to indicate that the last ham that transmitted has released the repeater and someone else can transmit. After announcing your callsign and “listening,” your radio should light up for a few seconds after your transmission with a signal and possibly a short tone coming back from the repeater. If nothing happens after you release the transmit button, it’s entirely possible that you have configured your settings incorrectly (or you’re out of range of a repeater). All repeaters I’ve seen will at least have a few seconds of silent signal after a transmission.

For your first few contacts, it’s also important to indicate to the other ham that you’re new to the hobby. You’ll likely make mistakes, and hopefully the other ham will identify these mistakes for you and help you correct them. Almost all hams love teaching and informing others, so don’t hesitate to ask for help or clarifications when necessary.

If you don’t hear anything back, but you know your transmission is going through, try repeating your callsign followed by “listening” every minute for a few minutes until you get something, or switch to a different repeater. It’s also a good idea to leave your radio on and tuned to the frequency of a repeater in your area. Sooner or later, you’re bound to hear someone. You’re more likely to get a contact on a repeater that’s linked to other repeaters, as this system inevitably covers a larger geographic area.

If you’re having trouble hitting repeaters around you, try utilizing your log-periodic antenna. This requires that you know the location of a given repeater—you need to point your antenna at the repeater in order for it to be effective. You may also need to twist the antenna such that the radiating elements are vertical, as repeaters’ antennas are generally vertically polarized. This is shown in Figure 8-9. Note how the antenna in the figure is twisted so that the elements are vertically polarized. High-gain antennas such as this can be utilized to reach repeaters with obstacles in the way, such as the trees shown in the figure. Instructions on how to use this antenna are located in the following chapter.
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Figure 8-9

Using a log-periodic antenna for repeater contacts

Summary

Congratulations! You now know how to operate your first piece of amateur radio hardware! With your handheld transceiver, the BaoFeng UV-5R, you can use repeaters to contact individuals many miles away. Repeaters will be your gateway to the amateur radio community until you invest in fixed hardware that allows for longer-distance operation. Repeaters are convenient ways to talk with others; additionally, they serve as common gathering places for hams to talk with one another.

Clearly, handheld transceivers are versatile devices that open the door to the world of amateur radio. Many hams don’t purchase other radio equipment than handheld transceivers for years after they get their license as these devices are so capable. It’s well worth it to spend your time getting to know your handheld transceiver, as it will become an invaluable tool in your radio toolbox. BaoFeng radios do have shortcomings, particularly in their voice quality and receiver hardware. If you enjoy amateur radio, it might be a good idea to invest in a more expensive HT—you can find decent used models in the range of $100 or $200. In the next chapter, we will use an HT and a specialized antenna to communicate with other hams via a satellite.

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