Programming VHF/UHF Radios
By Ken Larson, KJ6RZ
Programming a new VHF/UHF radio usually proves to be a frustrating experience for most new amateur radio operators. In the words of Helen Tallen KG6DUK “I thought I could just buy a radio, turn it on, and it would work”. Unfortunately a new radio must first be programmed for simplex and repeater operation before it can be used to communicate with local hams.
Most VHF/UHF ham radios are packed with dozens of interesting features. Only a small number of these features are actually used for normal communications. The remainder are provided for special communication modes occasionally used by experienced hams. The problem is that the few features that you do need are usually imbedded in the complex menus used by the radio to set up all its other advanced features. To make matters worse, there are no standards for the set up menus. Each radio is different. Even radios made by the same manufacturer differ in their set up menus. This is not only exasperating to new hams, it drives experienced amateur radio operators crazy also. To program a radio you must read the radio’s instruction manual to learn what the specific set up procedures are for that radio. Don’t every loose the radio’s instruction manual! Without it, you will not be able to reprogram the radio.
While radio manuals are getting better, it is still very easy to get totally confused the first time that you try to set up a radio. Again, explanation of how to set up the basic functions that you need are mixed in with the complex descriptions of the advanced features. The purpose of this article is to give you an idea of what you will need to do to set up a new radio for basic Simplex, Repeater, and Memory operation so that you will have an idea of what to look for and concentrate on in the instruction manual for your radio. The Alinco radios installed at the East County Sheriff’s Station (ECSS) ARES/RACES Emergency Communication Center will be used as an example. These radios are fairly typical in their set up procedures. Also, by reading this article you will know how to operate the radios in the comm. center should it become necessary for you to do so during an emergency or to support one of our many CVARC Thousand Oaks public service events.
If you have trouble relating the process explained below to your particular radio, send me an email at firstname.lastname@example.org. As Jerry KC6JSO discovered, at CVARC help is available. We will give you a hand in setting up a set of easy to follow procedures for your radio.
SIMPLEX OPERATION: Simplex is the simplest mode of operation. Simplex does not involve a repeater and is used to communicate with a “near by” ham who is approximately in your line of sight. During a recent ARES/RACES simplex test, Pete Heins N6ZE used a low power handheld radio to talk to hams throughout Conejo Valley from the top of Tarantula Hill in central Thousand Oaks. All of Conejo Valley was in Pete’s line of sight. In a similar test, conducted in a hilly residential neighborhood near the Thousand Oaks Library, myself and another amateur radio operator were able to communicate only a half mile or less using handheld radios operating in the simplex mode. Being on top of a high hill or having a tall antenna with a “clear line of sight” is very important when using simplex communications!
To operate simplex you have to tune your radio to the frequency that you and the ham that you want to talk to agree upon. In addition, you have to turn off your radio’s repeater frequency shift function. Frequency shift is utilized only when communicating through a repeater. It is not used for simplex operation. Finally, set your radio’s output power to an appropriate level (usually low or medium power), set the squelch control to eliminate background noise, and turn the volume control to a comfortable listening level. You are now ready to begin simplex communications. These steps are described in more detail below. For the Alinco radio, simplex set up requires you to use a row of buttons located below its display as shown in Figure 1.
The buttons are labled as follows:
The pushbutton in the upper right hand corner of the radio is the power on/off button. The small knob to the left of the power on/off button is the volume control, and the larger knob below it is the frequency tuning knob. Other radios will have similar controls, with the exception of the smallest handheld radios which use push buttons instead of volume control and tuning knobs.
Frequency Selection: Radios have two operating modes, VFO mode and memory mode. To set the radio to the correct frequency you must be in the VFO mode. If your radio is in the memory mode, there will be an M or a channel number appearing somewhere on the radio’s display. For the Alinco, an M appears on the left edge of the display when it is in the memory mode. If you are in the memory mode, the V/M button must be pushed on the Alinco to enter the VFO mode (the M will disappear from the display). The Variable Frequency Oscillator (VFO) is the module that controls your radio’s frequency. Turning the tuning knob causes the radio to change frequency in very small steps. If the person that you want to talk to is on a frequency of 147.555 MHz and your radio is tuned to 144.000 MHz, it will take you all day to “crank” your tuning knob to a frequency of 147.555 MHz. To move across the band quickly with the Alinco, push the MHz button. The display will change to 144. Turn the tuning knob 3 clicks. The frequency display will change from 144 to 145, then 146, and finally 147. Pushing the MHz button again puts the radio back in the normal mode. Now turn the tuning knob until you reach 147.555 MHz. Many radios operate in this manner. Others allow you to enter the frequency that you want directly from the radio’s key pad, in the case of a handheld, or from the key pad on the microphone.
Turn Off Shift: When communicating through a repeater, the frequency that you are listening to (the repeater output frequency) will be automatically changed (shifted) by your radio to the repeater input frequency when you begin to transmit. In simplex mode you do not want this to happen. In simplex mode, the frequency that you are listening to is also the frequency that you want to transmit on. To ensure that this happens, you must turn off the shift function. On the Alinco you will notice the word SHIFT displayed above the MHz key. Since SHIFT is written above the key, it means that you activate the Shift function by first pushing the Function (FUNC) key and then the MHz key. Repeating this two keystroke operation will cycle you through three options, minus shift (a – appears on the display), plus shift (a + appears on the display), no shift (no symbol appears on the screen). It is this last option that you want for simplex operation.
As just described, the Alinco has one function engraved on each function key and a second function, requiring the use of the Function key, displayed above each key. On some radios, pushing the Function key causes the labels displayed above the function keys to change, thus changing the function performed by each key when it is pushed. Pushing and holding down the Function key for 1 second causes a third set of labels to appear. Other radios may show two functions above each key and differentiate them by color, gray and blue for example. Gray colored functions are executed directly by pushing the key under the label. Blue functions require you to push the radio’s Function key and then the key under the blue label. Your radio will likely use one of these approaches to select functions such as turning off the frequency shift.
End FunctionSelection : Usually, the radio will return you to the normal radio display after selecting a function. Occasionally you can get stuck in the function selection process. It is therefore important to know how to terminate a function selection. On the Alinco, you push the V/M key to terminate or close function selection. Find out how to do this on your radio before you use the Function key to avoid getting stuck in the function selection mode.
Power Level: Most radios have several transmit power levels, typically High, Medium, and Low. To minimize interference to others and to minimize the drain on your batteries, set your radio to the lowest power level needed to communicate with the person that you are talking to. A good level to start with is Medium. On the Alinco, H/L (High/Low power) is displayed above the Call key. This means that power selection is a second level function. Push the Function key followed by the Call key to select power level. Repeating this set of key strokes will cycle you through the High (nothing displayed), Medium (Mi displayed), and Low (Lo displayed) power levels of the radio. Stop at the setting that you want. Most radios set the power level in a similar way.
Squelch: On many radios the squelch and volume are concentric controls (an inner knob and a larger outer knob on the same shaft). For the Alinco there is a Squelch key (SQL). For concentric controls, turn the squelch knob (usually counter clockwise) until you hear continuous background noise (hissing). Now turn the knob the other direction until the hissing stops and the radio is quiet. This sets the sensitivity of your radio so that you can hear others without the nuisance of background noise. On the Alinco this is done by pushing the SQL key and then turning the tuning knob in the manner just described for concentric squelch controls.
Volume Control: Finally set the volume control to an audio level that is comfortable.
Receiving: You should now be able to receive the transmissions from the person that you want to talk with.
Transmit: To transmit, push the PTT (Push To Talk) key on your handheld radio or on your microphone. Wait a second after pushing the PTT key before speaking to give your radio time to enter the transmit mode. If you do not do this, the first word that you speak may not be clearly transmitted. Speak in a normal voice. Speaking too loudly will distort your transmission. Also, talk across your microphone, from the side, instead of directly into it. Talking directly into the microphone can cause background hissing.
EMERGENCY SIMPLEX OPERATION: Simplex operation is a very important mode that everyone should know how to use. During a natural disaster, the local repeaters may fail. If that occurs, amateur radio operators assisting with emergency communications traffic must switch to the simplex mode to continue emergency operations. This is done by setting up their radios for simplex operation, using the procedures described above, and tuning their radios to an agreed upon simplex frequency. On Tuesday night May 18 at 7:00 PM we will be testing our emergency communications simplex operations on 147.885 MHz. If you would like to be part of an important test, set up your radio for simplex operation and check into the exercise following the directions that will be transmitted to all participants that evening.
REPEATER OPERATION: Repeater operation permits communications over an extended area, even with a handheld radio. A repeater located on a high hill or mountain top has line of site coverage over a considerable area, often 15 to 20 miles.
A repeater amplifies signals it receives on its input frequency and retransmits them on its output frequency throughout its area of coverage. As a repeater user, you will listens to others on the repeater output frequency. This is the frequency that is listed for the repeater in repeater directories. For example, the output frequency for the Bozo Repeater is 147.885 MHz and the Grissom Repeater is 146.850 MHz. The repeater input frequency, for 2 meter repeaters, is off set or shifted either +600 KHz or -600 KHz from its output frequency. When you transmit to a repeater, the output of your radio must shift + or - 600 KHz, as appropriate, to the repeater’s input frequency. The off set for both Bozo and Grissom is negative. The Bozo output frequency is 147.885 MHz. So when you transmit to Bozo, your radio must transmit at a frequency of 147.285 MHz. You must program this + or - off set into your radio in order to use the repeater.
Most repeaters in metropolitan areas utilize an access tone to avoid receiving and retransmitting signals actually intended for a different repeater operating on the same frequency. This tone is known as a PL or CTCSS tone. There are actually 39 tones available for use ranging in frequency from 67.0 to 250.3 Hz. A repeater will only retransmit signals which contain its particular PL tone. For example, the PL for Bozo is 127.3 Hz while that for Grissom is 94.8 Hz. To utilize a repeater, your radio must be programmed to transmit the PL tone which the repeater is expecting. If you don’t, the repeater will ignore your signals. In some cases a repeater will not use a PL tone, for example the Ojai repeater does not use a PL. In that case you will not program a PL tone into your radio for that repeater.
Programming your radio to work with a repeater is similar to programming it for simplex operation with the addition of the +/- off set and the PL tone. For the Alinco radio, the programming proceeds as follows:
Frequency Selection: If the radio is in the memory mode (there is an M showing on the display indicating memory mode), then push the V/M key to place the radio in the VFO mode. Tune the radio to the output frequency of the repeater that you wish to use, 147.885 MHz for Bozo, using the same tuning procedures that were used to select a simplex frequency.
Select +/- Shift: Select the appropriate +/- off set for the repeater that you plan to use. On the Alinco this is done with the SHIFT key. The word SHIFT appears above the MHz key which means that the FUNC key must be pushed followed by pushing the MHz key to activate the Shift function. Performing this two keystroke operation causes a – to be displayed indicating that the radio is now set up for a negative off set. Performing the two keystroke operation again causes a + to be displayed indicating a + off set. Performing the operation again causes the – and + signs to disappear, indicating that you are back in the Simplex mode. Perform the operation as many times as needed to achieve either a – or a + off set, as appropriate for the repeater that you will be using.
Select PL Tone: If the repeater that you will be using requires a PL tone, then you must select the tone which the repeater expects. Tone is selected on the Alinco radio by pushing the TS/DCS key. Pushing the key once will cause a T to be displayed plus a tone frequency. Turn the tuning knob until the tone frequency expected by the repeater is displayed. Complete the tone selection by pushing the V/M key to exit the selection process. The normal display will return, except that a T is now showing on the display indicating that a PL tone has been selected. Pushing the Alinco TS/DCS key multiple times will cause other functions to appear on the display. If this occurs, continue pushing the key until only a T accompanied by a tone frequency is shown on the display and proceed as described above.
Power Level: Set the radio’s transmit power level to the lowest power needed for the repeater to clearly receive your signal. A good level to start with is Medium. Set this power level in the same way as was done for simplex operation.
Squelch: Set the squelch in the same manner as was done for simplex operation.
Volume Control: Finally set the volume control to an audio level that is comfortable.
Transmitting and Receiving: You are now ready to communicate with others via the repeater. Before beginning to transmit, make sure that the person that has been transmitting is really finished before starting your transmission. Then delay a little longer so that if someone has emergency traffic, they will be able to break in and use the repeater. If all is quiet, then you may transmit by pushing the PTT key on your handheld radio or microphone. Remember to wait a second after pushing the PTT key before speaking to give your radio and the repeater time to enter the transmit mode.
RADIO MEMORY OPERATION: Programming radio simplex and repeater frequencies is a lot a work. After you have set up your radio for a particular simplex frequency or repeater, you can store that information into your radio’s memory so that you will not have to repeat the set up the next time that you want to use that simplex frequency or repeater.
Writing to a Memory Channel: Storing the information that you have programmed into the VFO is particularly easy on the Alinco radio. Push the V/M key to place the radio in the memory mode. An M will appear on the display. Turning the tuning knob will select different memory channels. The number of each memory channel will appear on the display as it is selected. Select an unused memory channel. The memory channel number will blink if that memory channel is empty. Other radios tend to do the same for an empty channel. Push the FUNC key followed by the V/M key to write the contents of the VFO into the selected memory channel, ie to do a memory write function (MW).
Memory Read: Once you have stored all of your favorite repeater and simplex frequencies into memory, all that you have to do is select the appropriate memory channel to begin operating on that frequency. To do this, you switch your radio from the VFO mode to the memory mode, pushing the V/M key on the Alinco, select the appropriate memory channel, and begin operating. For example, if operation on the Bozo repeater (memory channel 02) is desired, push the V/M key to place the radio in the memory mode (an M appears on the display). Turn the tuning knob until memory channel 02 appears on the display. Begin operating on Bozo. That is all there is too it.
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