What is the difference between lpd and pmr. Which range is better than LPD or PMR and is there a difference between them? Callsigns when using CBS LPD or PMR

Frequency bands intended for unlicensed use in accordance with the rules and laws of various countries.

(PMR446, Personal Mobile Radio - Personal mobile radio) is a European license-free mobile radio system in the VHF band with a frequency of 446.000-446.100 MHz and a maximum output power of 0.5 watts. It is intended exclusively for private use by the public. The range is intended for use on the territory of Russia and European countries.
In this range, the use of stations with a power of up to 0.5 watts is allowed in the United States.

PMR Frequency Grid

No. Frequency
1 446.00625
2 446.01875
3 446.03125
4 446.04375
5 446.05625
6 446.06875
7 446.08125
8 446.09375

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LPD
LPD (LPD433, Lower Power Device - Low Power Device) is a license-free mobile radio communication system in the VHF band with a frequency of 433.075-434.775 MHz and a maximum output power of 0.01 watts. Designed for private use by the public. The range is intended for use in Russia and some European countries.

Frequency Grid LPD

No. Frequency
1(1) 433.075
2(2) 433.100
3 433.125
4 433.150
5 433.175
6(3) 433.200
7 433.225
8 433.250
9 433.275
10(4) 433.300
11 433.325
12(5) 433.350
13 433.375
14 433.400
15 433.425
16 433.450
17(6) 433.475
18 433.500
19 433.525
20 433.550
21 433.575
22 433.600
23(7) 433.625
24 433.650
25 433.675
26 433.700
27 433.725
28 433.750
29 433.775
30(8) 433.800
31 433.825
32 433.850
33 433.875
34 433.900
35 433.925
36 433.950
37 433.975
38 434.000
39 434.025
40 434.050
41 434.075
42 434.100
43 434.125
44 434.150
45 434.175
46 434.200
47 434.225
48 434.250
49 434.275
50 434.300
51 434.325
52 434.350
53 434.375
54 434.400
55 434.425
56 434.450
57 434.475
58 434.500
59 434.525
60 434.550
61 434.575
62 434.600
63 434.625
64 434.650
65 434.675
66 434.700
67 434.725
68 434.750
69 434.775

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Which countries are allowed to use PMR and LPD bands
This information will help you make right choice means of radio communication, without violating the laws of the European country where you are going to travel. Having a walkie-talkie, you will always stay in touch with each other, regardless of availability mobile operator. In Russia, the LPD and PMR range is allowed, and the registration of unlicensed radio stations was canceled in 2007.

country use conditions
Austria allowed Free
Belgium prohibited prohibited
Germany allowed freely
Holland allowed free
Greece allowed free
Denmark prohibited prohibited
ireland forbidden forbidden
Italy allowed from channel #1 to #20 freely
Iceland allowed Free
spain forbidden forbidden
Cyprus allowed Free
Latvia prohibited prohibited
Lithuania prohibited prohibited
Luxembourg forbidden forbidden
Norway allowed Free
Poland allowed Free
Portugal forbidden forbidden
United Kingdom prohibited prohibited
Slovakia allowed Free
Slovenia allowed Free
turkey forbidden forbidden
Finland forbidden forbidden
France allowed Free
Sweden allowed Free
switzerland forbidden forbidden
Croatia forbidden forbidden
Estonia forbidden forbidden

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PMR (446 MHz)

country use conditions
Austria allowed Free
Belgium allowed Free
Hungary allowed Free
Germany allowed Free
Holland allowed Free
Greece allowed Free
Denmark allowed Free
Ireland is allowed freely, but you need to check subtones
Italy allowed general permission
Iceland allowed Free
Spain allowed Free
Cyprus allowed Free
Latvia is allowed to have a station type approval
Lithuania allowed Free
Luxembourg allowed Free
Madeira and Azores allowed Free
Malta allowed Free
Norway allowed Free
Poland allowed Free
Portugal allowed Free
United Kingdom allowed Free
Slovakia allowed Free
Slovenia allowed Free
Turkey allowed nominal permission
Finland allowed Free
France allowed Free
Croatia allowed Free
Czech Republic allowed general permission
Sweden allowed Free
Switzerland allowed Free
Estonia allowed Free

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FRS
FRS (Family Radio Service - Family Radio Communication) is a license-free personal mobile radio system over short distances in the countries of North and South America in the UHF band at frequencies 462 MHz - 467 MHz.
The range includes 14 simplex radio channels with a step of 25 kHz. The power of radio stations is 0.5 watts.

Frequency Grid FRS

No. Frequency
1 462.5625
2 462.5875
3 462.6125
4 462.6375
5 462.6625
6 462.6875
7 462.7125
8 467.5625
9 467.5875
10 467.6125
11 467.6375
12 467.6625
13 467.6875
14 467.7125

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GMRS
GMRS (General Mobile Radio Service - Basic Mobile Radio Service) license-free band, designed for use in the United States and Canada and includes 16 radio channels with a 25 kHz step. Power of radio stations - from 1 W.
In this range, a lower GMRS and an upper GMRS are distinguished. Most often, low-cost, non-professional walkie-talkies use the lower GMRS to expand the FRS range. GMRS 462 MHz - (462.5625-462.7250 MHz), up to 2 watts allowed in the US.

Two cars is a company, and three is already a column. And the more participants, the more difficult it is to coordinate. The question of operational and reliable communication is acute. It would seem that the simplest and most obvious option is cellular communication. But it has several serious drawbacks: dependence on the availability of a cell tower, the need to wait for a connection to be established, and operator services are not free.

We quickly and decisively get rid of the operator cellular communication, we pass from digital to analog, we go into the legally permitted frequency range - and we get a civilian radio station (CB, LPD or PMR) in front of us. We no longer depend on the infrastructure of an intermediary operator, we can quickly communicate with each other at the touch of a button, we pay only for batteries or battery charging. But here, alas, not without flaws.

There is such a thing as the range of stable communication. It consists of transmitter power, receiver selectivity and sensitivity, transmitting and receiving antenna efficiency, electromagnetic interference level, obstacles between the receiver and transmitter, and so on. That is, for maximum communication quality, we need to take a powerful transmitter and a high-quality receiver, install an antenna with a high gain, find a frequency free from interference and try to eliminate all obstacles. This is how smoothly and unobtrusively we came to a set of equipment for an amateur radio base station, with which you can communicate for tens, hundreds, or even thousands of kilometers)

Our task is more modest: as a rule, when moving in a convoy, a particularly large communication range is not required, several kilometers should be enough (provided that the crews are disciplined and do not strive to stretch out and get confused in all directions). The "entry threshold" is also important - it is obvious that the CB (27 MHz) range is optimal for land mobile radio communications, but in order to communicate in this range, you will have to install a rather long antenna on the car, which not everyone is ready to do - there are a lot of problems. On the LPD and PMR bands, the antenna length requirements are much lower. Therefore, the most logical option seems to be the purchase of portable transceivers in the LPD / PMR band (433 / 446 MHz), that is, exactly what most people mean by the word "walkie-talkie".

There are a huge number of models in the LPD / PMR ranges, as a rule, most of them come in a set of "two radios". The legislation provides for limiting the maximum transmitter power for LPD (433MHz) - 0.01W, for PMR (446MHz) - 0.5W. The use of external and directional antennas is prohibited. In fact, you can easily purchase an LPD radio with a power of, for example, 4 watts - and where does the radio frequency center look?))

Since we are not paid money for reviews, the walkie-talkies were collected as best they could - from the kadabra.

Selected the following company:

Midland GXT-1050

Voxtel MR-190

Motorola T5622

* apparently a subtle hint that the radio can be "opened" to high power

Cobra MT600-2

Baofeng UV-5R

This walkie-talkie covers a much larger range than conventional LPD/PMR. It is possible to work on reception and transmission from 400 to 480 Mhz. Also, there is a second range (the so-called "two") 136-174Mhz, which allows us to regard this transceiver as an amateur radio device.
It was possible to test it with standard and extended antennas, so the tables will periodically meet one or both options.

Separately, out of standings (because the connection with her is such that it’s easier to shout out the window to each other) CB-portable

Midland Alan 42

We immediately decided that we would conduct tests exclusively while in the car, that is, we deliberately complicated the conditions. Everything had to be as close to reality as possible, because you won’t constantly stop on the side of the road and climb a hillock to transmit some information to a distant subscriber.

The area for testing was chosen of two types: a city with dense buildings and a country road. At the same time, two series of tests were carried out in each location: in the presence of direct visibility and in the presence of obstacles between two subscribers. For the test, two first-generation Kia Sportage cars were taken, on which car CB radio communication kits were installed - through it we maintained constant communication between the crews.

The tests themselves looked like this: both cars stop at one point (A), one car remains in place, the second one drives off to a given distance (measured by a GPS navigator in a straight line) and stops. We turn on the first set of walkie-talkies, the first car calls the second, then vice versa, we write the assessment on a subjective ten-point scale, turn off the walkie-talkies, take the next set, and so on, until we check everything. After that, the first car continues to stand in the same place, and the second one goes further, and everything starts all over again.

And so, the first location is "city":

The long and straight Bogatyrsky Prospekt came in very handy. Communication in a straight line was measured along it. The results were recorded from the point of view of the subscriber in this particular vehicle. That is, there were situations when the subscriber in car No. 1 did not receive a subscriber from car No. 2 at all, at the same time in reverse direction the connection was quite good. Perhaps this is due to the presence of electromagnetic interference at different points in the location, which clogged the reception, but did not interfere with the transmission. Here are the results:

City, line of sight

City, with obstacles (houses, urban areas) Either we were unlucky that day, or it’s always like this, but the LPD band turned out to be totally crap - there were some kind of interference everywhere, builders, security guards, almost on every channel either something was making noise or someone was talking. The PMR range, despite its only 8 channels, was clean - a minimum of interference and extraneous conversations. I was very surprised by CB - after 2km it became extremely difficult to communicate. However, this is natural for the city, because. on 27 MHz, any urban man-made man, who goes unnoticed on 433-446 MHz, strongly interferes with interference.

1. Baofeng took the lead by a wide margin - this is not surprising, with 4 watts of power and an effective antenna it is hard to compete with it. At one point, the standard antenna began to receive even better than the elongated one - perhaps a more efficient antenna, due to its sensitivity, was able to "catch" some kind of interference that the short one "did not hear."
2. Midland GXT-1050 was in second place in terms of range.
3. Unexpectedly, the third place was taken by Voxtel MR-190.
4. Cobra MT600-2 - one of the walkie-talkies in this set turned out to be defective and refused to transmit normally, the connection had to be evaluated in a one-way mode.
5. Motorola T5622 is an amazing walkie-talkie. It would seem that a fairly powerful signal, which confidently opened noise reduction up to 2 km in a straight line. But the modulation is so disgusting that it is absolutely impossible to make out the words. Sensation that a person is talking with his mouth sealed. Therefore, there are two scores in the cell - voice intelligibility scores and Roger Beep intelligibility scores (transmission end signal, sent by the radio automatically when the button is released). Honorable last place.

Midland Alan 42 participating out of standings dropped out of the fight already at 500m. The fact is that even at such a ridiculous distance, I had to get out of the car into the street - when transmitting from the passenger compartment, he could not even open the noise reduction from another subscriber. He worked for the transfer by 1 point, after which it became clear that there was no point in wasting time on his further testing. Again, the axiom was confirmed that it makes sense to work in the CB band only if you have a fairly serious set of equipment. There is no place for portables.

Moving to the second location - "suburban track"

Straight track By arrangement of seats, the picture turned out to be the same as in the city - Baofeng, Midland GXT, Voxtel, Cobra, Motorola. In the test with bumps at 2000m, Baofeng unexpectedly lost to Midland - most likely we stumbled upon some kind of interference at this frequency, perhaps it was worth trying other channels, and the picture would change.

The test "in a straight line" had to be stopped at 2000m due to the fact that a smooth asphalt straight line ended there, and then there were turns. Therefore, it was not possible to establish the maximum communication range in a straight line outside the city. But the purpose of our study was not so much to identify the most "long-range" walkie-talkie, but to determine at what distance, in general, you can comfortably communicate when driving in cars. By the way, CB outside the city worked quite well at all the above distances.

The conclusion is this: when using the usual popular PMR / LPD, sold in sets, when driving both around the city and outside the city - you should not separate further than ~ 1.5 km - any uneven terrain, turn or other obstacle, and the communication range immediately drops very much. And the optimistic range figures stated in the brochures should be safely divided by 2.

Many thanks to teammates in kadabra: @Turbocat , @BeeRMaN , @Michspar and @Cooleroff for providing radios. And also @Michspar and @Cooleroff special thanks for their help in running the tests.

-What are they needed for?
- frequency bands. What is it and which one to choose?
-subtones, why they are not “subchannels”;
- radio communication range (power, antenna and relief);
- power consumption and weight. An important topic for tourists;
-accessories. headsets and laryngophones;
-how to communicate.

Everyone used to go without them, but walkie-talkies add an enormous amount of convenience and safety to your adventures. For example:

In the mountains, communication within a bundle, a group. If, of course, you are tired of yelling “railing of freedom” and “understood”, through the wind;
- inside the group in any hiking trip, where there are 10 or more participants, the walkie-talkie at the navigator, trailer and leader will give the leader a ton of comfort and save extra nerve cells if the group is stretched. You can stop far-running “moose”;
between cyclists. I don’t understand how cyclists lived without walkie-talkies in general) People ride constantly at different speeds, and it gets boring to stop, waiting for everyone at each fork;
communication with people who have gone on reconnaissance saves time;
- in search and rescue operations;
-when some people go to the radial exit, and some are waiting for them at the base. Any event where there is a stationary camp. Alpine activities are the same;
- in a civilization where it is a pity to call a mobile phone while roaming;
- on a ski slope where everyone skis separately, but wants to meet at the same time and go home or be able to signal for help.

Now closer to the point.

About frequencies.

Have you seen the waves yet? For those who haven't seen it, here they are:

And here's the actual physics. How often the waves wave is measured in Hertz (Hz).

Everything! All physics!
With a further choice of the number of hertz, our state (Russia) helps us, where the following ranges are allowed for general unlicensed use:

CB (26-27 MHz)

LPD (433-434 MHz)

PMR (446 MHz)

For licensed radio operators, a two-meter range of 144-146 MHz is opened. For those who do not have a license, but run fast through the forests - too. The same range is the only way to organize communication between the group and the base at the climbing event due to its greater range compared to LPD and PMR.

Other ranges cannot be used. They are for airplanes, sailors, police, etc. There, hooliganism will be punished, because you will really interfere (for example, out of ignorance of the balabol at frequency 16 of the sea channel, which serves to send an SOS signal).

The physics shown above tells us that the CB will perform better in rough terrain, but:

Walkie-talkies in this range are large, you can’t put them in your pocket, they require a lot of voltage to work, they are heavy.

But all these long numbers lead people, especially unprepared ones, into depression and despondency. And you don't need to know them! And even imagine: you want to switch to another frequency and you have to dictate a new number to someone ... on the walkie-talkie .. darkness! Humanity strives to make everything easier and more convenient. People agreed that they would communicate on certain frequencies and gave them numbers - already shorter and easier to remember. These numbers are called "Channels".

And they made walkie-talkies in which you can only set the channel number, they don’t even have a keyboard or knobs to set an arbitrary frequency.

Now it’s enough to just say “Vasya, go to the eleventh”. If Vasya has such a channel walkie-talkie, then he doesn’t even need to know what LPD is, what frequencies he has and other crap. As a rule, he does not even need to know that he has LPD. You just need to select the number 11 on the screen.

Midland LPD channel radio with selected channel 11
Usually on such channel radios, the channel is selected with two arrow buttons, by “scrolling” the numbers in a circle.

Important point: Please note LPD and PMR channels do not overlap with each other! If one person has a canal walkie-talkie LPD, and the other channel PMR, then they will not be able to communicate!

You can determine the range of your walkie-talkie by looking at the instructions, google the walkie-talkie model, or, which is usually faster and work “in the fields”, simply by looking at how many channels the walkie-talkie offers to choose. If 69 - LPD, if 8 - PMR.

If you want to be able to communicate on all bands, buy a channel walkie-talkie with LPD and PMR (for example, Midland GXT-850) or a frequency walkie-talkie. For example, I have a frequency Baofeng UV-5R, which is in the photo above, it can also climb into the two-meter range. This walkie-talkie has two modes (switched by a red button on top).

1. Frequency mode. In it, on the radio keyboard, I type the numbers of the frequency in which I am going to work. Like a phone number.

In the upper line of the walkie-talkie on the left (frequency), the frequency of the 2nd LPD channel is dialed, which is selected on the walkie-talkie on the right (channel). Now these two radios can communicate with each other.

2.Pre-recorded channel selection mode. This walkie-talkie has 128 memory cells in each of which I can write down my frequencies from a computer using a special wiring and give them my name. Firstly, it is useful when I want to communicate with a channel walkie-talkie of a certain range, but I do not remember by heart that terrible long frequency number. I will record the traditional LPD and PMR grid into the walkie-talkie and, if necessary, select the desired channel. Secondly, no one will judge me if I suddenly want to communicate with my friends not in the generally accepted channel, but on a frequency between channels, for example, and I'm too lazy to enter it manually every time. I can put it on the walkie-talkie and name it “DRUH 1” for example. Or in my get-together it is customary to communicate on a channel with a certain subtone (what it is will go below), I can also record it from a computer, and then choose with arrows as on a convenient and simple channel walkie-talkie.

There are even walkie-talkies without screens at all.

Channels are poured there only through a wire from a computer and are selected on it with a separate toggle switch. Such walkie-talkies are the cheapest, but reconfiguring them in the field will no longer work, and in order to get in touch with the owner of another customizable walkie-talkie (at least a channel one, at least a frequency one), you must remember by heart what is written there inside its electronic memory. Then a person with a customizable walkie-talkie will get a chance to connect with you.

Subtones

If channels were invented to make it more convenient to connect with someone, then subtones were invented to disconnect someone from this :)

Everyone who turned on the radio every time heard the builders, taxi drivers, store guards, while he did not want to hear them. For such cases, subtones were invented.

By turning on one of the analog (CTCSS) or digital (DCS) subtones (codes, as they are also called), you will stop hearing everyone else who does not have the same set turned on: channel + subtone.

For example my Midland walkie-talkies GXT 1050 (channel LPD) 38 analog and 104 digital subtones. If I use one of the LPD channels, the probability that someone is already talking in the channel I have chosen is 1/69, and if I turn on one of the analog subtones, then this probability will be 1/2622. It seems I will be in silence :) And with a subtone, chaotic “PShShSh” practically disappears.

The second LPD channel and the fifth analog subtone on the Midland radio

At the same time, this is not encryption, everyone who will have the same channel / frequency, will hear you closing for a subtone. Therefore, it is useless to swear at the builders who interfere with you - most likely they are also closed to the subtone and do not hear you.

And you have to understand that this is not a separate channel, the subtone only prevents your walkie-talkie from sounding if someone else's transmission is on the same channel as yours. And the radio is not mobile phone, on one channel only one can speak the rest are listening. If there is a subtone, when you start the transmission, you may not know that at that moment the taxi drivers are also saying something, and the transmission will not come out. In general, get out of the city and you will be happy there :)

There is such a problem with subtones that if the channel frequencies are accepted the same all over the world, and all manufacturers make the same channels, then whoever makes subtones as he wants. Those. in order to connect the walkie-talkies of one model by subtones, you just need to set the same value for each of them, and in order to connect different models, you need to dance with a tambourine. I have to dance like this, because I have walkie-talkies from different manufacturers. My models are very popular, and the question can often arise not only for me: “How can I combine subtones from different manufacturers?” Here you will meet someone in the forest ...

Analog subtones(CTCS) . They are labeled as they wish. In some walkie-talkies (like my Baofeng UV-5R) they are called by their natural identifier - a frequent tone that is broadcast along with the voice.

In the Baofeng Uv-5R radio, the analog subtone is selected in the 11th menu item.
I don’t enter the subtone frequency (71.9) here, but select it with arrows from the list in the radio’s firmware.

It is this frequency that is recorded in the first column in the subtone correspondence table from a cheerful guy with a cool haircut (Column heading - Freq, from “Frequency” - frequency) (You can easily find similar tables on the Internet yourself). And in other walkie-talkies, the manufacturers followed the same logic as with the frequencies-channels - they decided not to bother the user's brain with long numbers and called the subtones serial numbers. But each manufacturer has numbered a slightly different list of tone frequencies. Someone numbered 38 subtone frequencies, someone 39, someone 43, 48, 50, 64. Then they began to copy these lists from each other, trying to achieve compatibility ... In general, now it’s easiest to determine which list in one or another walkie-talkie used - by the number of available subtones. On the vast majority of LPD / PMR radios there will be 38 of them. And then the numbering can be seen in the column with the heading "38". How it looks like you have already seen in the photo before last on the Midland radio with the fifth analog subtone.

Digital subtones (codes) (DCS). For them, the natural designation is a three-digit number.

In the Baofeng Uv-5R radio, the digital subtone is selected in the 10th menu item.

The same nonsense as with analog ones, only the manufacturers have not yet agreed which impulse to consider as zero, and which one ( binary system do you understand). As a result, the designations "n" ("direct") and "i" (inverse) appeared. These are not two different incompatible worlds. For each direct there is a fully compatible inverse. And some, like the same Midland, simply gave them serial numbers (it will look like in the same photo "Midland with the fifth analog subtone", only over the subtone number there will be an inscription not "CTCSS", but "DCS").

Radio power

PMR works over longer distances, because. its maximum permitted power in the Russian Federation is 100 times greater than LPD (10 mW LPD and 0.5W PMR);
- the more powerful the radio station, the steeper.

Let's deal with the first. Everyone saw the speedometer of a car. Judging by it, the average car CAN accelerate to 200-odd kilometers. Why aren't such cars banned from driving in a city where the maximum speed limit is only 60 km/h? Yes, because they also CAN drive at the speed allowed. If the driver violated the speed limit, the driver is fined, not the manufacturer of the car. It's the same with radios. Almost all walkie-talkies sold in Russia have a power of 5 W or more, but they all have a button or menu item that switches the walkie-talkie to low-power mode, which is within the permitted range. Everything! The manufacturer made sure that the walkie-talkie could be used within the law, and it is honestly sold in the Russian Federation. And the fact that physical the person uses it at a higher power - everyone sneezes.

That is, in fact, the power of the radio is that LPD and PMR are the same. As a rule, most models have a power of about 5 watts.

Now about the power of the radio in general. The distance at which the radio is heard is proportional to the square root of the power. Those. to double the range, the power must be increased by 4.

Example: A 5 W radio (most of them) finishes off in a certain area, say, 3 km. The same 8 W radio will reach only 3.7 km. And an 8W battery eats much faster than a 5W one. Are 700 meters worth it? And you with more powerful walkie-talkie they will hear a little further, but you will hear the rest of the “losers” with low-power walkie-talkies as well. By the way, all the same, walkie-talkies in LPD and PMR bands work in line of sight. Behind the houses, the bends of the relief, no one will hear anything anyway, no matter how powerful it is. Although in theory you can contact the ISS flying over your head.

And do you need range at all? In practice, not often. Of the options for using radio communications that I have listed, the range is needed only with a radial exit of part of the group or during search operations.

If you still need range, then:
- you can go to the two-meter range (do not go to other frequencies, except for the interval of 144-146 MHz, and do not flood in it);
-buy an antenna longer. For example, my Midland radio has a non-removable antenna, and for Baofeng, instead of a standard antenna, you can screw a longer Nagoya antenna and enjoy life;
Buy yourself and the whole group digital walkie-talkies. For example Baofeng DM-5R. With the same power and antenna, the radio range and quality will be greater.
- get up, finally, higher :)
The main thing to remember is that any information on the seller's website about the communication distance is nothing more than marketing and a “spherical horse in a vacuum”.

power usage

I must say right away that the answer to the question: "How much battery is enough?" No one will give you the exact number. It all depends on the nature of the use. On reception, the radio "eats" several times less than on transmission. Do you prefer to listen or talk?

Walkie-talkies come with AA/AAA battery/batteries (like my Midland GXT 1050, which runs on my favorite AA batteries) or their own batteries (like my Baofeng UV-5R).

It would seem that for an autonomous trip, you need to take Midland and that's it. But in fact, if you think about it, everything is a little more complicated.

Below I will give the calculations for my walkie-talkies. Of course, it is not necessary that you will have exactly the same choice, but the conclusions will be interesting, and you will be able to study your options by analogy (although the Baofeng UV-5R is a VERY popular walkie-talkie, and among the channel ones I often see my Midland or slightly younger models , not very different from it). There is really something to think about here.

The weight of the equipped Midland radio is 277 grams, the weight of the Baofeng UV-5R is 212 grams or 221 with an enlarged antenna.

Weight of 1 IKEA battery (2450 mAh) or Eneloop pro (2500 mAh) 31 grams. In the Midland walkie-talkie, you need 4 pieces, i.e. the kit weighs 124 grams.

The weight of 1 standard Baofeng UV-5R battery is 79 grams.

Those. taking batteries to Baofeng is easier. But…

Midland is still a slightly better tuned walkie-talkie, including in terms of energy consumption (it’s not for nothing that it’s more expensive. And it’s also overpaid for the company) and in theory it will work longer. Yes, and I can use AA elements from it in Garmin GPS, a headlamp or my Powerbank - to charge the phone.
I can supply the Baofeng UV-5R with: a) an extended battery, b) a 6 AAA battery pack (looks like a standard battery), c) a 6 AA battery pack (looks like an extended battery).
In the photo, a walkie-talkie with a standard battery and an extended battery (actually an AA battery pack, but there is no difference in size)

On the left is a Baopheng Uv-5r walkie-talkie with an enlarged branded 6 AA battery / bat block, on the right is the same walkie-talkie with a standard 6 AAA battery / bat block

Baofeng UV-5r walkie-talkie and extended battery or AA battery pack

Open battery pack for AA

Baofeng UV-5r battery scale plate. IKEA LADDA batteries were inserted into the butblocks, but you can insert whatever you want.

Suppose I go to live in the taiga, on a hike 6 ks, in general, for a very long time outside of civilization, and I take walkie-talkies with me, hoping to charge them.

In the case of Midland, I take out 4 AA cells from it and connect them to the ROBITON MobileCharger, which can charge 4 AA / AAA at once.

What if I take Baofeng UV-5R?

Option 1. I take a battery pack to it. Doesn't matter if it's AA or AAA.

Both have 6 batteries. Here I will definitely have to use at least two USB outputs. One for ROBITON MobileCharger and 4 batteries, the other for example for ROBITON SmartCharger Traveler for two more. (and I carry both in my camping electronics kit) And if the first device is busy, then I can only charge ⅔ of the walkie-talkie with the help of two “frogs”. Sadly.

Option 2. I take Baofeng UV-5R with a standard battery. And I can charge such a battery with one ROBITON SmartCharger Traveler frog, but that is wildly inconvenient (baofeng batteries do not hold well there). So I'll take a glass to charge the baofeng battery from USB.

Charger from USB on the left, on the right is the charger that comes in the standard set upon purchase.

Here's the math. Moral of the above: Choose a walkie-talkie based on your tasks, conditions and available equipment.

Useful stray

Herms. All the walkie-talkies I see fit there, except for healthy CBs (27 MHz). From there you can hear and speak. Drawstring is adjustable and comfortable.

Headsets. They are more comfortable, especially on a bike. It is inconvenient with them if you keep the walkie-talkie in your backpack, and the headset is on you - you will definitely tear it off when you take off the backpack. And also, if you take off and put the walkie-talkie somewhere, and do not remove the headphone wire from it, then you will not hear the walkie-talkie if someone tries to shout to you. Be careful when choosing - not all headsets will fit all models at once.

Laryngophones. In theory, it's cool that the wind does not blow into the microphone. This thing takes the voice off the neck. But you need to learn how to use and keep in the right place.

Tangents. The remote PTT button is not always combined with a microphone (then it is a headset). It is convenient to attach this to the handlebars of a bicycle.

How to use the device?

On the side of each walkie-talkie there is a PTT (Push to talk) button, it is also called a “tangent”. While someone else is talking on the same channel, it is USELESS to press it and it is not necessary. This is not a mobile phone, you WILL NOT be able to outshout the interlocutors. They won't hear you while someone is holding the button. In radio communications, we learn to be polite - we waited for the end of the speech on the radio, pressed, we say our own. They said they let me go, the radio went into signal reception mode.
It is good to accustom yourself to speak not immediately after pressing the button, but after waiting a second at the beginning of the transmission and at the end (we say to ourselves the number 21 or any other two-digit number that is not a multiple of 10 or the union "and"). The fact is that you don’t know how the interlocutor’s radio is set up, she needs to quickly distinguish the signal you transmit from random interference on the air, and if she doesn’t do this on time, then the beginning of your phrase will disappear. The case symbolizing this error, the miners will understand me:
First: - So what did you decide, I untie the knot at the end?

Second: - Pshshshrazvyazyvay.

What was it? "Yes, untie" or "Don't untie"?

In order to understand the interlocutor that you have completed the transmission of information, and now your radio will go into receive mode (you will release the PTT), it is customary to say “Reception” at the end of the phrase
- We are fine, how did you receive it? Reception.

Understood, you're fine, hang up. end of connection.

At the beginning of a communication session, it would be good to make sure that the interlocutor hears you and, if there are more than two of you in the working group, tell him who and who is calling (first the call sign of the one they want to hear, and then your own).

At this moment, Petya realizes that some kind of sound is coming from the valve of his backpack. He remembers that he has a walkie-talkie, that he must have missed the communication session. Petya starts to take off his backpack and fish out a walkie-talkie from there. Vasya can't stand it and repeats.

Petya, tell Vasya how you hear me. Reception.

Petya finally got the radio.

Petya is in the channel, I can hear you well. Reception.

That's probably all for now.

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What connection do we use while doing active sports and recreation?

Cellular telephone, not always convenient, not always working.

Satellite, but in some cases this is the only connection with the "large earth".

Now about everyday realities.

Someone bought “soapbox” walkie-talkies, someone snatched something more impressive, some of them had radio amateurs, many band stations.

When all stations have the same, usually there are no problems, everyone hears each other. And when the stations are different, how to “make friends” with them. After all, not all people engaged in the same kind of activity have the same radio stations.

There can be many situations requiring the construction of different stations:

- Skiing, you want to build walkie-talkies with a guide.

- You go on vacation in several cars, in a large company.

- Communicate in the mountains with other groups of climbers.

If you are in trouble, ask for help.

- Collaborate with other teams on rescue missions.

Let's first look at what radio stations are.

From simple to complex 😉

"Soap dishes"

"Soap dish" - "soap dish discord" ®

and so they are done according to the transmitter power and frequency.

You probably noticed that there are a different number of channels on the walkie-talkies: 69 channels, 22 channels, 8 channels. n with a different number of "subchannels", remember, there are no subchannels, in most cases you call tone CTCSS or digital DCS noise suppressor with this terrible word. What it is, see the appendix, at the end of the material.

There are also different markings, on boxes, walkie-talkies, or under batteries: LPD, PMR, FRS / GMRS.

Let's see what is here and why.

FRS / GMRS is an American standard for household transmitters that operate on frequencies that are not allowed in Russia for use by a simple layman. It will not be possible to legally use these walkie-talkies.

PMR ("Personal Mobile Radio"), 8 channels are allocated for walkie-talkies with a transmitter output power of not more than 0.5 watts. The European standard for household transmitters (446.00625- 446.09375 MHz) due to the grid spacing of 6.25 kHz, they do not match almost anything, except for the same PMR radios standard. On amateur radio stations where there is no 6.25 kHz step, you can tune in slightly deviating from the given frequency. Registration of radio stations is not required.

LPD (Low Power Device) can be used freely - registration of radio stations is not required. They operate in the range 433.075-434.775 MHz. The most successful household radio stations for active pastime, especially if you bought the “right” models that can be tuned to a slightly higher power (up to 3x W), compared to the allowed 0.01W. There are models with a twisted antenna, you can replace it with a longer antenna from a professional or amateur radio station, which will greatly increase its receiving and transmitting characteristics.

See the appendix for a table of correspondence of frequencies to numbers of channels and tones of the squelch.

P.S. The use of LPD radios (SRD) is not allowed in the following countries: Belgium, Denmark, Finland, Prland, Luxembourg, Portugal, United Kingdom, Spain, Lithuania, Latvia, Estonia, Croatia, Turkey.

There are no such restrictions for PMR radios, you can safely go abroad and use them freely.

As for FRS / GMRS, this range is prohibited primarily in Russia. 😉

amateur radio stations.

How Not All Apples Are Equal

So not every Kenwood is a Kenwood.

(amateur radio wisdom)

A good connection is not cheap. With these words, I want to start a story about mid-range equipment.

Chinese KENWOOD TK-K2AT, TH-K2AT and TK-150S band 137-174 MHz, or TK-K4AT, TH-K4AT and TK-450S band 420-470 MHz work with any LPD / FRS / GMRS "soap dishes" price less than 100 $ piece. These and other similar devices are widely sold in our country.

BUT! Oh, if you only knew how much I dislike such "buts" myself. Walkie-talkies of this price range, with the declared characteristics - a pig in a poke.

Reliability = non-failure operation, durability, maintainability.

That's just the reliability in these KitaKenwoods and is lame.

How quickly it will stop working is also not known. This equipment, class, lucky - no luck, tested on our own experience.

Kenwood is a good manufacturer of professional equipment, for adequate money. If your Kenwood kit breaks down, remember Kenwood has nothing to do with it, he never saw these stations.

There are so-called "two-bend" radio stations that combine the bands of interest to us, the so-called two-meter range and the 70cm range, they are not named so by chance, this is a reflection of the wavelength in the name. These are the frequencies of 137-174 MHz and 420-470 MHz, in the second, as you remember, household walkie-talkies "soap dishes" fall.

So why are we interested in the 2 meter range, do you think? And in fact, a lot.

The first and very important argument is that rescuers of the Ministry of Emergency Situations work on it.

Secondly, a huge "army" of radio amateurs communicates in this range.

Thirdly, it has good penetration in mountainous and wooded areas, the 70cm range wins only in dense urban areas.

Being involved in active sports and recreation, it is very foolish to assume that you, your friend or other people around you in your sport will not need any third-party help. You can not count on a mobile phone everywhere, and you yourself have come across this. So being able to ask for help in time can be very important. When arriving in a new area, find out the frequencies of the radio stations: guides, voluntary rescue units and the Ministry of Emergency Situations. For the Ministry of Emergency Situations, this is usually a frequency of 164.450 MHz, but you must find out on your own what frequency the receivers of local rescue services and their call signs are tuned to.

The calling frequency of radio amateurs (usually 145.500 MHz), all neighboring radio amateurs conduct their communications here, and many have stationary equipment of much better quality and finely tuned than in the Ministry of Emergency Situations. You understand, some people are so addicted to their hobbies that they are ready to spend a lot of money and that's it. free time to your passion in order to achieve good results. It should also be noted that radio amateurs repeatedly received distress signals and transmitted information to rescuers, so many lives were saved at different times.

Taking this into account, we can conclude that having a 2-meter range in your walkie-talkie is not very superfluous. Radios of this level require registration if you are going to use them legally. There is nothing complicated in this, but more on that later.

Yaeski-yaeski.

Yaesu- well-known brand

among radio amateurs

and is synonymous with high quality

amateur radio stations.

A good combination of price = quality simply forces us to dwell in more detail on the models of this manufacturer. Here are three models of portable stations that you should pay special attention to.

YAESU FT-60R

YAESU VX-3R

YAESU VX-6R

All three stations are dual-band, cost in ascending order.

Briefly about the advantages and disadvantages thereof. All of them are very similar in their characteristics.

YAESUFT-60 R

Pros: Full 5W transmitter power, price, ability to use: lithium, metal hydride and nickel-cadmium branded batteries, the ability to run on batteries. Dustproof, waterproof.

Minus: large and heavy compared to the other two. Not a very thoughtful headset connector, so as not to fly out, you have to press it with a rubber band.

YAESUVX-3 R

Pros: Very compact and light, 130g. Dustproof, waterproof.

Cons: Weaker transmitter, no more than 3W. Only lithium branded batteries.

YAESUVX-6 R

Pros: Full 5W of transmitter power, compact, medium size between FT-60R and VX-3R. According to the requirements of moisture protection, the station complies with the JIS-7 standard (immersion to a depth of 1 meter for 30 minutes). Only lithium branded batteries.

The Yaesu VX-120 stands apart, it can be described as “hope”.

This radio has only a two-to-one range, but its merits are not in a wide reception range, but in reliability. Waterproof and shock resistant to military standard MIL STND 810 C/D/E.

Radio Options

The antenna is the best amplifier.

Whatever your "cool walkie-talkie"

with a bad antenna it doesn't matter.

Antennas.

All antennas supplied with radio stations have very weak characteristics due to their broadband. Since we need antennas for very narrow ranges, you can purchase them and win in quality and communication range.

Yaesu ATU-6B (420-470 MHz) good antenna to seventy, if you put it on the LPD station, for example, the four hundredth midland, you will win great as a connection.

Yaesu /Vertex ATV-6XL Antenna for 136-174 MHz band, tuned to the required frequency by trimming. A cropping card is included in the kit.

Cut it to 145 MHz and the second to 164 MHz and get the most efficient antennas for these frequencies.

Opek 601HV dual band antenna 136-174MHz-420-470MHz. It has slightly more gain than a standard antenna. Flimsy, requires careful handling, strongly breaks at the point of articulation with the coil. The quality has been very unstable lately. With minor home modifications, it shows slightly better results than the standard antennas for the FT-60 or VX-6.

When using radio communications at a considerable distance from each other, the use of antennas tuned exactly to the frequency on which you work is mandatory, since when using standard multi-band antennas, there is no chance of being out of touch or receiving only fragments of phrases.

Headsets - PTTs

Headsets or the same handsfree are very convenient, which frees your hands from the radio station, but you can just as quickly receive the information transmitted to you.

A PTT is a remote unit on a wire that connects to your walkie-talkie with a microphone, speaker and a transmit button. It also has a headphone jack in most cases.

A very handy thing, regardless of the type of station. The radio can be in an inner pocket (for example, so as not to freeze) or in a backpack, and the PTT is brought to a convenient place and connected to the station with a twisted wire.

Batteries

There are different types of batteries: lithium, metal hydride and nickel-cadmium. Briefly about the pros and cons of them when used in radio stations.

Lithium - have the largest capacity, with a modest battery size. Accordingly, long-term energy efficiency. Their disadvantage is that they are very afraid of negative temperatures, quickly lose tension and the ability to continue working.

Metal hydride batteries have a lower capacity for the same size, and are not as afraid of negative temperatures as lithium. They do not have a “memory effect” and can be recharged without waiting for full discharge. But they have a relatively high self-discharge current. This means that they lose their charge when they are simply stored waiting to be put into service. For one week of storage of a charged battery, you will lose somewhere around 20% capacity, respectively 20% of the operating time.

Nickel-cadmium batteries have the lowest capacity of the above. They can deliver the most current. They have a "memory effect" and require full discharge before recharging. But their advantages are in low self-discharge current. Therefore, they still enjoy the attention of operational services.

Battery cassettes

Convenient devices for AA batteries. They can help out a lot when there is no way to find an outlet to charge the station.

Cons: due to the many intermediate contacts between the batteries (batteries), micro-resistances are obtained that prevent normal current transfer, while the station will not work at full capacity and for as long as on a standard battery. Inserting larger-capacity AA batteries there and using it instead of a regular battery is also not profitable due to micro resistances. It is necessary to solder all connections with short (about 10-15mm) and thick wires. Well, that's a completely different story.

Increasing the range of radio communication within the group in a given area.

If your area of ​​interest is around a static object (house, gatehouse, campground, etc.), then you can put a stationary base antenna there with good reception characteristics (for example, Diamond X-50) and receive to a small portable station connected via an adapter. or install a station with a high transmitter power and a more sensitive receiver, which equals better reception of weak signals (for example, an automobile FT-2800 on the "two" or FT-7800, FT-8800 on both bands), but in both cases use thick wires (7 -10mm) with a small attenuation factor for your chosen range.

If there is such a “base”, but there is no person in it, everyone dispersed around the bush, and it is impossible to shout from one portable station to another because of the range or terrain. You can connect an Echo Repeater (Parrot), which is a small digital tape recorder, to the “base” station, for an average of 60 seconds of recording. connected instead of a PTT to the station.

It works very simply, it records the voice received at the base station, at the end of the reception it puts the station into transmission mode and plays your words on the air. You yourself and the correspondent who is not available in direct radio visibility hear this. He answers you and the cycle repeats the required number of times. The cost of such devices is comparable to the cost of two simple or one good "soap dish".

Frequencies for work on the air.

2 meters - 144-146 MHz

Here is a small illustration explaining the distribution of frequencies in the range of 144-146 MHz.

From the beginning, what frequencies you should NOT work on, say while skiing or boarding. Do not step on frequencies that are marked with a color other than green in the plates above. With your negotiations, you can interfere with other participants in the broadcast, and they, in turn, will interfere with you. Don't make each other uncomfortable.

Where possible, as you probably guessed, at those frequencies that are marked in green, but there are a few caveats. The frequency 145.500 and two frequencies to the right and left are underlined, commonly used by radio amateurs for local communication with each other. Therefore, do not occupy these frequencies either. There are 25 frequencies in the range of two meters, among which you can definitely choose a free one. Be respectful and polite to everyone on the air, and everyone will be polite to you.

As is known, in Russian Federation there are several ranges that can be used by citizens for their own purposes. The most popular range, CB, is covered quite extensively in the magazine, but here VHF bands were not particularly considered. It's time to correct this shortcoming.

So, in Russia there are 3 ranges that are available for use by citizens for their own personal purposes.

CB range, 11 meters, 27 MHz with a permitted power of up to 10 W, (and according to new data, up to 4 W) it is allowed to use radio stations with any type of antenna.

LPD range, 70 cm, 433 MHz with a permitted power up to 0.01 W, it is allowed to use radio stations with built-in antennas.

PMR band, 70 cm, 446 MHz with a permitted power up to 0.5 W, it is allowed to use radio stations with built-in antennas.

Terms of use

Everything is clear with CBS, and the rules for using portable and portable radio stations have been described more than once on the pages of the magazine. In short, portable car radio stations of the CB range with a power of up to 10 watts are not subject to registration. In this case, the antenna used must have a gain of less than 1.73dBi. Stations used stationary, with stationary antennas (bases), are subject to registration in in due course. Deviation from the above, strictly speaking, is not legal. But what about LPD and PMR?

If your portable radios operating in the LPD and PMR bands do not have the ability to operate at powers above the legal limits, then you have nothing to worry about. You can use these ranges as ordinary citizens, and no one will say a word to you. Exceeding the established power limits transfers the station from the civilian category to the amateur category, and if you do not have the appropriate amateur radio category, at least the fourth, then the use of such a station becomes illegal and any authorized person can withdraw your radio station and roll a fine for radio hooliganism.

The organization Roskomnadzor monitors the observance of order on the air. Her responsibilities include identifying radio stations that do not comply with the norms established by law for the permitted power. In practice, if you use walkie-talkies, albeit with increased power, not systematically, and do not interfere with anyone, then most likely no one will be interested in you and the station will not be taken away from you. In any case, when using the air, respect other users of the air, especially if they use frequencies legally. This applies to all civilian bands.

IN general view, when choosing a range for communication, remember that:

1. There is always scattering of radio waves - the wave power of an equidirectional source weakens in proportion to the square of the distance (simply due to the fact that the energy is distributed over the area of ​​\u200b\u200bthe sphere, the radius of which is equal to the distance to the source). That is, at some distance, the antenna will not be able to catch more energy than is contained in the ambient electromagnetic noise).
2. An obstacle to the propagation of radio waves is any object whose geometric size is more than half the wavelength. The opposite is also possible, when a shorter wave passes through, for example, the reinforcement of a reinforced concrete building or a steel mesh with lower losses than a wave whose length is much greater than the distance between the reinforcement or mesh cells.
3. There is attenuation of radio waves - the energy of the waves weakens in the propagation medium. To do this, there are many tables and coefficients for different weather, different climates and other factors that affect attenuation in the atmosphere.
4. The earth, in the first approximation, has the shape of a sphere (geoid) - the waves propagate almost rectilinearly. Therefore, effective propagation occurs mainly within direct radio visibility (due to refraction, it is slightly greater than optical visibility). The line-of-sight distance depends on the height of the antennas and is calculated approximately as follows: R = 4.12 * √ (h1² + h2²), where h1 and h2 are the heights of the transmitting and receiving antennas.
5. Ionospheric reflection and birefringence, re-reflection from the surface of the Earth and the ionosphere, curvature in the atmosphere, VHF waves are weakly affected and are usually not taken into account. On the CB bands, long-range transmissions, reflections of signals from the ionosphere and propagation over distances of more than a thousand kilometers are possible.
6. The higher the frequency, and accordingly the shorter the wavelength, the shorter the antenna used at this frequency. Each antenna has a gain (due to the ability to radiate and receive a large fraction of the energy in the right direction).
7. The higher the frequency, the less ethereal noise is present on the band. On the CB band, the air is very dirty, heavily clogged with industrial interference and long-range transmissions. On VHF, due to the lack of transmissions in the sense in which they are present on CB, the air is much cleaner, which has a positive effect on the range and quality of communication. However, in cities, LPDs and PMRs can also be heavily polluted by industrial interference.

LPD/PMR CB frequencies

LPD, 69 channels 433.075 - 434.775 MHz, step between channels 25 kHz.

PMR, 8 channels 446.00625 - 446.09375 MHz, step between channels 6.25 kHz.

CB, 40 channels 26.965 - 27.405 MHz, step between channels 10 kHz

Radio range LPD/PMR and CB

On the boxes of LPD / PMR radio stations, the range is written in kilometers. I can only say that usually this figure in real conditions can be divided by 2, by 4, or even by 8. The indicated range can be obtained under the condition of direct visibility and the absence of obstacles. The practically measured communication range of any walkie-talkie in the 400-470 MHz range, at a power of 0.5-2 W, with a sensitivity of 0.18 mKv and a half-shortened antenna, will be as follows:

– in the city 0.3-0.6 km
– in the forest 0.4-1 km
– in the village 1-3 km
– in the field 2-5 km
- in the mountains 5-25 km (in line of sight)

Portable MW radio stations at 27MHz: 1-10km. (depends on interference, antenna and terrain)
These distances can vary by a factor of two, it all depends on the terrain and interference. If instead of a standard shortened antenna, you use a 1/4λ antenna, then the range will increase by 1.5-2 times. When using a directional antenna, the range will increase by 3-7 times. And if you increase the power by 2 times, then, other things being equal, the range will increase by another 15-20 percent.

As for portable radio stations of CBS and VHF bands, this is a separate issue, since they have much more power and, for example, LPD and PMR radio stations are moving from civilian to amateur category. Since LPD / PMR stations are not available for a car, you can go for the trick and adapt a regular portable to work from a car. To do this, buy car antenna, for the range of 420 - 450 MHz, install a connector (adapter) in the station and connect it to the antenna, this will increase the communication range by 2 - 3 times.

What to buy, LPD, PMR, CB?

If you are not a radio amateur with a call sign and the corresponding category, then the best choice for you it's CBS, LPD/PMR radio stations. LPDs are compatible with amateur radio stations in the 430-440MHz band. PMRs operate outside of the amateur radio band (a plus in some cases), and PMR stations are more powerful, cheaper, and allowed in more countries around the world.

Differences in radio range between LPD and PMR radios

There are three indicators on which the communication range depends:

1. transmitter power
2. receiver sensitivity
3. antenna gain.

If these parameters are approximately the same for LPD and PMR stations, the range will be the same. There will be no difference between them. The difference appears when you change any of the three parameters listed above. For example, a 500mW PMR station will provide greater range than a 10mW LPD station.

Callsigns when using CBS LPD or PMR

Since all three bands are civil, users of such radio stations can come up with their own call signs or not use them at all. You can use your name as a call sign. For example: Masha, Vasya, Petya, digital callsigns, etc. If there are many people with the same names in your group, use a name with a number (Vasya1, Vasya2, etc.) or nicknames.

Improvements for CB LPD / PMR radio stations

Are they required? For cheap models, yes, they are desirable. Often radio stations come across poorly tuned, because of this, the communication range and intelligibility fall.

Tone and digital noise suppression, or what are CTCSS and DCS

They are used mainly in professional communications, but radio stations of civilian bands have also inherited. These are special signals (subtones) that are transmitted along with the signal generated by the station. On radios working with each other, the code must be the same. Thus, interference and other signals on the frequency are filtered out and do not interfere with the conversation. The conversations themselves are not encrypted.

CTCSS ( Tone-Coded Squelch System) tone coded squelch system (38-50 codes)

DCS (Digital-Coded Squelch) Digital Squelch Code (83-104 codes)

Both encodings are designed to filter interference from other radio stations or household interference. CTCSS is an analog system, so when a radio station with a neighboring tone appears next to you, you will also hear it. For example, you are using channel 4 with tone 22, if a radio station appears nearby on channel 4 with tone 21 or 23, you will hear it. There are no such overlays in DCS.

I must say that such codes and subtones take place not only in VHF radio communications, which include LPD and PMR, but also in CB, where protection against long-distance passages is currently quite important. However, there are very few equipment capable of supporting such an anti-interference system.