Midland g5 excitation ULF radio way to eliminate. Overview of walkie-talkies Midland G5 - affordable communication

Midland g5 excitation ULF radio way to eliminate. Overview of walkie-talkies Midland G5 - affordable communication

14.08.2023

Midland G5 has been produced since 2006 and is considered one of the successful and best-selling PMR radios. At first glance, it looks like the G-225, but noticeably smaller in size. The circuitry of these radios is almost identical. The receiver is built according to the super-heterodyne circuit, the input is not broadband, a 446 MHz quartz filter is used, which is very good. The first IF is 21MHz, the second IF is 450kHz. Schematic solutions are classic. G5 powered by 3 AAA batteries (3.7-4.5V). Inside, the station is made with high quality, the installation is neat, nothing dangles, where screens are needed, all the adjusting elements are located on one side. The body is made of cheap plastic, but quite grippy, the first impression is pleasant.

appearance of the radio station G5

About the number of channels
Radio frequencies for PMR stations are always 8, to which 38 CTCSS subtone codes are added. DCS encoding is not supported here. Total 8×38=304 virtual channels in which users do not interfere with each other. This is more than enough, given the short communication range (1-3 km) of these walkie-talkies. It turns out that on a conditional territory with a side of a square of 10 km, 608 people can communicate without interfering with each other! In fact, more, because at the same time everyone will not talk.

Channel numbering can be indicated by a 3-digit number. For example, when asked to switch to channel 120, this means 1 radio channel with code frequency 20. Channel 838 is radio channel 8 with code 38, and so on. And in total there are 304 such combinations (from 101 to 838). Despite the fact that 8 channels are usually more than enough, in the G5 they can be increased. Below is a table of correspondence between PMR channels and frequencies (in MHz).


Shop purchase
I bought the cheapest option costing 999 rubles. for a couple of radios without headsets, chargers and batteries. These accessories are easy to make yourself (I don't like the standard accessories) or buy them separately.

In the store, you need to insert 3 AAA elements into each walkie-talkie and make sure that they work by asking the manager to go to another corner of the store. Audibility should be excellent, the signal is legible. I have not met, but they say that marriage comes across.

Home check
Now let's check the G5 (with the help of instruments) for compliance with the declared characteristics, and, if necessary, adjust it. For this: we measure the receiver sensitivity, transmitter power (at a load of 50 ohms), antenna resonance, deviation level, squelch threshold, frequency setting accuracy, consumption currents in different modes.

I should note that in addition to the level of noise reduction and frequency, nothing had to be adjusted. The characteristics are as follows:

  • current consumption in standby reception with economizer 14mA
  • in standby receiving and scanning mode, without economizer 28mA
  • with backlight on, without economizer 34mA
  • at maximum volume 60mA
  • current consumption in transmission mode 230mA
  • current consumption when the radio is turned off 0.5mA
  • receiver sensitivity approximately 0.18uV (12db sinad)
  • the opening level of the noise reduction is 0.17 mkv (this is after adjustment, it was 0.5 mkv)
  • transmitter deviation ±2.7kHz.
  • real transmitter power (at 50 ohm load) 210mW (0.2W)
  • frequency setting accuracy ±200Hz.
  • You can power the station from a voltage source of 4 - 6V with a current of 400mA.
  • Duration of continuous work of G5 with accumulators 1000 mA/h. measured by the YAESU method (6s transmit, 6s receive, 48s standby receive), is more than 20 hours (VX-3R works 7 hours). The time of continuous operation of the G5, in the standby reception mode with rare reception and transmission sessions, was about two days.

    The amplitude-frequency characteristic of the receiving path is visible on the graph, everything is fine here. A smooth blockage is visible towards high frequencies and even a limitation from below, as it should be. The two vertical lines show the frequencies 300Hz and 2700Hz. There are no complaints about the frequency response of the receiver.

    Let's compare some important characteristics of the Midland G5 with modern, miniature, VHF amateur radio stations:

    modelJ RX without economizerJTX at max. powerTX powerfeels. RXdimensionsweight
    VX-3R61ma1.1-1.3A1-1.5W0.16mkv47x81x23mm130gr
    IC-P7A80mA1.3-1.5A1.5W0.18mkv47x81x28mm160gr
    DJ-S45CQL60mA450mA0.5W0.18mkv57x98x28mm164gr
    Midland G528ma240mA0.2W0.18mkv50x85x25mm65gr

    Setting
    Checking frequency matching. We take a frequency meter, in extreme cases, a receiver that has the ability to work in SSB at 446 MHz, for example FT-817. If the discrepancy is more than 500Hz, adjust the frequency by carefully turning the trimmer capacitor CT201 with a non-inductive screwdriver. I had one station tuned exactly, the other 600Hz lower. I had to adjust it. Frequency setting accuracy is important when communicating at maximum range, when signals are weak.

    I want to be careful! Do not adjust the frequency by ear, without instruments! You will knock down the frequencies, but you will not be able to set it back. If there is no device, do not touch it!

    In my kit deviation level was set up perfectly. However, if necessary, it is regulated by a trimming resistor RV2. The optimal deviation is about ± 2.5-3 kHz. If you do more or less, then with a weak signal, speech will be less intelligible, and with a strong signal, distortion is possible.

    There are no complaints about the modulation (frequency response of the transmitter). There is a rise in high frequencies, speech is legible even in noise, with a weak signal level. The modulation quality (by ear) does not differ from pros and amateur radio stations.

    Sometimes there is such a picture, one walkie-talkie from the kit receives signals loudly, and the other the same signal is much quieter. It's not about sensitivity. Misconfigured in some instances receiver IF circuit, it is located to the left of the LTM 450HTU filter, in the photo below. The easiest and most affordable way to configure it looks like this:
    1. Remove the back cover, connect the power and turn on the radio.
    2. Set the maximum volume.
    3. Press PTT on the other radio and bring it up so that a small whistle is heard.
    4. With a non-inductive screwdriver (this is important!) Slowly turn the IF circuit.
    5. We achieve the maximum volume of the whistle.
    6. The setup is finished, we assemble the radio.

    Squelch Threshold in both radios was very high (about 0.8 μV), because of this, weak but intelligible signals were not heard at all. We decrease the squelch opening threshold by turning the RV1 resistor clockwise until the station hisses, then we go back about three degrees and leave it like that. After that, the broadcast came to life! Distant and faint signals began to be heard.

    After setting up the set of two G5s described above and modifying the antennas, the communication range increased by about 60%, from the one before the setting. The effect is clearly positive and I recommend that you check the purchased walkie-talkies.


    G5 radio setup items

    When to enable CTCSS
    In the city, numerous interference from PCs, cable networks, other conversations, etc., are eliminated by turning on CTCSS. The range of communication with CTCSS drops by about 10%, because the signal-to-noise threshold increases, at which the presence of a subtone signal is detected. It is recommended to turn on CTCSS when your signals are strong and the interference from other correspondents is weak, there is a line of sight or the correspondents are standing still.

    Disassembly with an antenna
    With the built-in helical antenna, I found two main drawbacks. The antenna has a length of 35mm (not enough) and more importantly, it has a resonance peak in the region of 467MHz, but 446MHz is needed. This means that the antenna efficiency is poor, this is the main factor reducing the communication range. To eliminate these shortcomings, it is possible in different ways.

    Setting up a native antenna consists in adding two turns or a loop, there is a place for this. Thus, we shift the resonance towards 446 MHz, this will give a small positive result. The efficiency of the antenna will improve slightly, but it will remain greatly shortened. In my G5, for some reason, an antenna was installed designed for the FRS range, which has 26 turns, an example in the photo.

    Full size ¼λ antenna(the best option!) is made from a piece of wire 155-162mm long (depending on thickness), which is soldered instead of a spiral. The wire must be elastic (to keep its shape), insulated. In the upper part of the case, where the antenna ends, we cut out a hole for the wire to exit. It is not necessary to adjust such an antenna, since its resonance is wide and you won’t miss 466 MHz, and if you miss it, it will work much more efficiently than the “native” spiral. Instead of a wire, you can use a piece of thin (4-6mm) coaxial cable of any resistance. It is necessary to cut off about 150-160mm and short-circuit the central core with a braid on both sides. A coaxial cable is good because it bends and it’s not scary to put the station in your pocket or backpack. The photo shows two pieces of wire of different thicknesses and a ½λ antenna.


    native antenna (35mm) and new (161mm) from 50 ohm cable

    Only with a ¼λ antenna will you get a feel for what the G5 is capable of. In terms of efficiency, a full-sized antenna is equivalent to increasing the transmitter power by about 4 times. This means that any radio station with a shortened 2-3W antenna will be heard as well as a G5 with a ¼λ antenna. You can compare the efficiency of the new antenna in transmission mode, according to the readings of a selective voltmeter (field indicator). Communication range will increase by 20-50%. In dense building conditions, the difference may be insignificant, but the stability of the p / connection will improve.

    External antenna
    If you want to use the G5 with a car or fixed antenna, install an SMA or BNC connector in the station. Since the impedance of the antenna input is 50 ohms, there will be no problems with connecting any external antennas in the 400-470 MHz range. The communication range with the antenna on the car increases by about 50-100%, compared with the spiral. When connecting a stationary antenna (three 5/8λ) on the roof of the house, the range will increase by 100-300%. Communication stability is improved, signal fading is reduced in motion.

    A directional antenna will give you even more range. But! Here it is necessary to make a reservation. The fact is that at 446 MHz, with an increase in the communication range, its stability decreases. This means that communication at a distance of 15 km can be established, but at different times of the year, day and in different weather, the connection may disappear or deteriorate greatly, and then be restored again.

    At frequencies of 446 MHz, do not chase the range! Communication stability is a more important indicator. The G5 is good as a personal radio with a range of 0.5-3km under normal conditions and 5-10km with line of sight.

    Earphone
    I almost never use a headset. In the city, for me, the earpiece is more in demand, stick it in your ear and calmly listen to the negotiations without attracting attention. On a hike, the earpiece is also useful, put the station in the inner pocket, the earpiece in your ear and it is not afraid of frost, wind, rain, etc. The earphone is convenient to use in a very noisy room or in a car.

    I made an adapter to which you can connect any headphones with a standard 3.5mm jack. When connected in parallel, the volume is too loud, even when the level is 0, so I connected them in series (to increase the resistance and reduce the volume). The photo shows how I did it: photo1, photo2.

    Headset
    I made it from a headset from an old Philips phone. Everything fit in it, it was only necessary to add a 2k resistor in series with a microphone, which, when a button was pressed, sat on the case. Using a headset usually results in a reduced communication range because the radio is under clothing.

    Lanyard
    To prevent the station from getting lost or falling out of your hands, we use a hand strap (lanyard). It provides additional options for mounting the radio in any place on the equipment, backpack, tent, etc. Bracket for fastening on the belt, not very reliable, you need to make sure. At the top of the bracket there is a slot into which we thread the belt. If necessary, it can be expanded with a file. It is convenient to carry the radio station on a belt, in a shirt pocket (where it fits easily) or in a cell phone case: photo1, photo2.

    Incompatibility with HAM radios
    Many amateur and professional radios can operate in the 446MHz region, but are not compatible with PMR radios. This is due to the lack of a 6.25 kHz step and a transmitter deviation of ±2.5 kHz (NARROW mode).

    For example, the popular radio stations FT-60, VX-3, VX-6 (in the disclosed version) cover the PMR frequencies, but with an offset, because they have tuning steps of 5,10,12.5kHz, etc. There is no 6.25kHz step and communication with PMR radios is not possible due to the discrepancy between frequencies. It is possible to try to combine channels with a step of 5 kHz, but it is useless. Communication will not be possible further than 30 meters, since the frequency mismatch of 1.25 kHz is too large for narrowband FM.

    Compatible with radios that do not have a 6.25kHz step
    So, we know that stations that do not have a 6.25kHz step cannot work with G5 (for example, VX-3, VX-6, FT-60, etc.). How to fix this incompatibility? Very simple, you will need a frequency meter or even an SSB receiver at 446 MHz, since an error of 200-300 Hz is not critical.

    We disassemble the G5, connect the power, switch to channel 4, connect the frequency meter. The frequency of channel 4 is 466043.75kHz, we shift the frequency by +6.25kHz up the frequency and we get 446050kHz. To do this, carefully turn the trimmer capacitor CT201counterclockwise with a non-inductive screwdriver. The frequency offset is controlled by a frequency meter or by zero beats of the SSB receiver.

    In VX-6, set the step to 12.5kHz, set the frequency to 466050kHz or another (see table below). Now both stations work fine with each other. True, now the compatibility of the G5 with other PMR stations has been lost, but this can also be solved.

    Making 16 channels
    Want to have two grids of 8 channels, please! To do this, you will need a frequency counter or an SSB receiver. The idea is based on a frequency shift of +6.25kHz. After that, the G5 becomes compatible with any amateur station with a step of 12.5kHz. It turns out two grids, PMR and HAM (amateur). Switching between grids produced by microswitch S1 installed near CT201. In series with the switch there is a capacitor C * with a positive TKE, its capacity must be selected (approximately 5-30pf). First, we set the trimmer, and after setting the shift and determining its capacity, we set it to constant. We connect it with the shortest possible wires to S1, which we display on the side, a few centimeters lower than the PTT button, for this we make a cutout in the case. The table shows the frequencies in both switch positions:

    Naturally, there will be no symbols on the display when changing the grid. In the HAM grid, the G5 works just as stably as in the PMR. There were no negative effects of this modification.

    Now you can work with both unlicensed PMRs and any other VHF radios with 12.5kHz pitch. If all PMR channels are busy, you have 8 more channels where you will not be disturbed. Do all soldering very carefully!

    Charger
    Since I have a minimum set of two G5s, after a while there was a need to charge AAA batteries. There are three in the station. I bought GP 1000mA batteries. You can charge them separately or directly in the radio station. Charge current \u003d battery capacity / 10, which means that a 1000mAh battery needs to be charged with a current of 100mA for 16 hours.

    As a memory, I found a cell phone charger lying around, OUTPUT 9V 350mA is written on the case, that’s it. I took a 2.5mm plug (three-pin) and soldered instead of the native one to charging (+ on the tip, - on the body). See photo of the finished design.

    Please note that 5V chargers will not work!

    Any charger or power supply with an output voltage of 9-10V will do. It is important that the charge current on the batteries be about 60-100mA. When testing charging, you need to check it with a milliammeter. In the list of standard accessories for the G5, there are chargers for the car and the network. Maybe it's easier for someone to buy than to do it yourself.

    Tests
    Test on the territory of the radio transmitting center showed that the G5 is resistant to jamming and out-of-band interference from a variety of other transmitters. In this respect, the Midland G5 is better than the Yaesu VX-3 with its broadband input, and here's why:

    On part of the circuit we see UHF, then a CF4 narrow-band quartz filter, then a mixer, a CF1 first IF filter and an IF. As you can see, any out-of-band signals will be cut before the first mixer.

    In the cold-10С the station continues to work. There is a non-critical frequency drift. For a river station without thermal stabilization of the reference generator, the result is good. It is possible to operate the G5 in the cold, but not for long, it is better to constantly keep it in the inner pocket of your clothes and take it out if necessary.

    Sensitivity I compared the G5 with the FT-817 by listening to conversations on different channels. By ear, both stations received weak signals approximately the same. There was no such thing that negotiations were sorted out on the FT-817, but not on the G5. The receiver sensitivity of the G5 is at the level of professional radio stations.

    Communication range in a typical microdistrict with 5 and 9-storey buildings, with dense buildings, ranged from 300 to 600 meters. This is a good indicator, which corresponds to amateur radio stations at a power of 0.2-0.5W. If one G5 "climbed" to the 9th floor, and the second "walked" along the street, the range increased to 1-2 km. In the woods, a pair of unmodified G5s had a range of 400 meters. After the alteration, the range was already 700m!

    On the box (in which the G5 is sold) they write: 1km in the city, 3km in the village, 5km in the mountains. For a transmitter power of 0.5W and a tuned antenna, these are real numbers, but a lot depends on the specific conditions.

    The real power of my station turned out to be half as much, 0.2W instead of 0.5W. I don’t know, maybe I got such a G5, or maybe everyone is like that. On the other hand, 0.2W is quite enough.

    Travel Tips
    I always advise climbers to take a radio station with them. In a campaign of any complexity, it will come in handy. Even if you are alone or in a group. My travel kit is shown in the photo.

    So that when using the radio station, there are no unnecessary questions from the "authorities" (although this is the rarest case, this did not happen to me), print out a small memo-reminder about the number of the decree of the government of the Russian Federation, according to which you have the right to use the radio.

    In the campaign, the radio station must be protected from moisture and frost! Keep in inner pocket. If the G5 was lying in the rain or dropped into the water, you need to remove the batteries, disassemble it and dry it. To do this, take a screwdriver. Disassembly takes 30 seconds, you need to unscrew five screws.

    Putting something like "AAA GP Ultra Alkaline" in the G5, you can take it on a hike for 3-7 days, without recharging and spare batteries, if work is carried out intermittently. When the radio is on all the time, the batteries will last for 2-3 days.

    Please note that the radio draws 0.5mA when turned off. The discharge occurs through the R79 + R33 chain (see the diagram), therefore, it is recommended to remove one battery from the compartment at night and during long breaks (from 2 hours or more) (to break the circuit).

    conclusions
    The characteristics of the PMR radio station Midland G5 meet modern requirements. At a price of 500 rubles apiece, it has no flaws. The sound quality of reception / transmission (after tuning) is no worse than amateur and professional models. Communication range corresponds to amateur radio stations with the same power (eg Alinco DJ-S45CQL). Excellent value for money! G5 can be recommended for hiking and cycling as a replacement for more expensive radios.

    It is advisable to carry out comparative tests of radio stations only after they have been checked and adjusted by instruments (rework). Then they will be more reliable.

    The modifications described above increase the communication range and ease of use of this radio station, so I recommend making them.

    PMR Radio Regulations
    1. Be polite on air.
    2. If the channel is busy, do not interfere in the conversation and do not interfere. Change frequency.
    3. If someone calls for help, answer and ask how you can help.
    4. Calling frequency for tourists (in the Caucasus), 8 PMR channel, without subtone or with code 08 (88.5Hz).

    a brief description of

    Midland G-5 walkie-talkies provide free radio communication anywhere in the world! They do not need to be registered with Rossvyaznadzor. The presence of additional functions - CTCSS subcodes, voice activation, channel scanning, end of transmission signal - make the use of the radio station very convenient. In addition, the radios can be powered both from the batteries that are supplied in the kit, and from batteries.

    Registration is not required

    Midland G-5 radios operate in the frequency band 446 - 446.1 MHz (this range is also called "PMR", that is, "private mobile radio"), their power when transmitting a radio signal is 0.5 watts. Such equipment is not subject to registration.

    Communication anytime, anywhere

    The manufacturer claims a radio communication range of 4-5 km. This is in conditions if both walkie-talkies are used on the street, and there are no obstacles between them. If one walkie-talkie is indoors and the other is outdoors, the communication range drops. Also, the communication range will be less when using walkie-talkies, for example, in the forest. These walkie-talkies are ideal for communication inside buildings. They use a signal in the range of ultrashort waves, and such waves have the ability to pass through obstacles. Therefore, with the help of Midland G-5 walkie-talkies, even interlocutors can talk, one of which is in the basement of the building, and the other in the attic or roof! Thus, with the help of these walkie-talkies, both builders and, for example, workers laying or repairing water pipes and communication lines inside the building can communicate. The walkie-talkies come with batteries and a charger that can charge two walkie-talkies from the mains at once. Instead of batteries, you can use AAA batteries ("little fingers"). The ability to power the radio from batteries is relevant in cases where it is not possible to charge the radio from an electrical outlet (for example, during a hike).

    It is very convenient and simple to use, there are many useful functions

    How to use the walkie-talkie can be described in a few words. Press the button - speak, release - listen. The PTT is a button on the left side of the radio. When pressed, the transmitter turns on, when released, the receiver turns on. Everything is simple! In the same block with the tangent, the key for turning on the display backlight is also made. You can talk on one of eight channels (channels differ from each other in frequency). The main thing is that the channel number for you and your interlocutor matches. It may happen that someone else uses the same channel as you. Of course, you can switch to another channel. But even this will not save you from situations when the walkie-talkies suddenly “come to life” with the voices of talking drivers (this happens, for example, near highways). There is an exit! You need to set the CTCSS subcode (Midland G-5 has 38 of them). It should also be the same for two interlocutors. At the same time, walkie-talkies transmit a signal encoded in a certain way, and receive only a signal with such a code, and signals that do not have such a code are “recognized” as extraneous noise and suppressed. It is very unlikely that anyone else, except for you and your interlocutor, may have walkie-talkies tuned to the same channel and receive / transmit the same subcode as yours in the coverage area of ​​the walkie-talkies. Thus, no one will interfere with your communication. But your conversation can still be heard by the owners of walkie-talkies tuned to the same channel and with coding not turned on, so we still do not recommend conducting confidential conversations on the walkie-talkie. The voice activation feature is very useful. Thanks to her, the radio is switched on in the “transmission” mode without pressing the PTT. This mode is very useful in situations where it is not possible to hold the radio in your hand (for example, while driving a car, while doing sports or industrial mountaineering). However, in this mode, the radio can be included in the transmission mode, and when it is not necessary, this circumstance should be borne in mind. It also has a channel scan feature. In this mode, the radio is tuned to receive the frequency of each channel in turn. If a signal from another walkie-talkie is received on this channel, then the scanning walkie-talkie remains in the reception mode of this channel, and you can talk with the owner of the walkie-talkie whose signal was received. This function is useful in cases where, for example, one of the people to be contacted is currently broadcasting something, but it is not known on which channel. Thanks to the "Roger beep" function, when the PTT is released and the radio enters the radio reception mode, a short beep is transmitted. It replaces the words "end of transmission, reception". Removable clip allows you to carry the walkie-talkie on your belt. If the clip is not in use, it can be removed.

    Warning: after alteration, you 100% lose the warranty. If you do everything according to the instructions, you can only physically spoil the radio - overheat, close the adjacent contacts with solder by accident, etc. After the improvements, if everything is done correctly, the communication range in the modified kit will increase by 1.5-2 times.

    We take the Midland G5 kit for 1000-1500 rubles. The price depends on the configuration and the greed of the seller. The package may also include 6 batteries, or 6 batteries and a charger. In principle, we only need walkie-talkies, so if there is a choice of kits with different prices, take whatever is cheaper.
    Photo: store set

    We unsolder the regular spring, which, according to the reviews of some radio amateurs, is tuned to resonance in the region of 467 MHz. Alternatively, you can lengthen it a little with a couple of turns, approaching 446. Then the appearance of the walkie-talkies will not change at all. But I prefer the regular quarter-tail. Moreover, it is easier to estimate the length of the tail by eye with the indicator, which I described in the last note (a primitive field indicator)

    Walkie-talkie with soldered spring:

    We remove the braid with an external insulator, remove the braid altogether. As for the insulator - I put it back. But you can not put, at your discretion. I leave it a little longer (5 millimeters), and then seal it with ordinary silicone sealant so that the antenna tail does not oxidize.
    As an option, you can solder to the braid, and not to the central core, but this is physically inconvenient, although the broadband of such an antenna will turn out a little better (but we don’t need it here).

    The length of the new antenna is approximately 155-165 mm.

    After the new antenna is soldered, we select the extra plastic in the plastic tails where the spring was hiding. So that the radio can be assembled, but at the same time the new antenna is tightly crimped.


    After that, we check the soldering of the antenna on the display meter from the last article. Compared to the second radio, the converted one should deflect the arrow when PTT is pressed much more noticeably (at the same distance from the device). If this does not happen, the problem is in the soldering. Despite the fact that even with a soldered antenna at a short distance, the walkie-talkie catches the second one, so don’t be deceived, you can’t check this way (one walkie-talkie to another).

    Next, turning on the radio, turn the noise reduction clockwise until the station begins to hiss. After that, turn counterclockwise quite a bit so that the hiss disappears.
    Be careful, different household appliances may sound at different frequencies. For example, I have a router on the 3rd PMR channel. When tuning, if there are frequencies with a background, it is better to tune in clean channels.

    If the station has become too sensitive and opens noise reduction, for example, on the first channel, when the transmission is on another, turn the noise reduction back a little. Also, with extraneous crackles on the channels, the noise reduction should be returned a little, because. the radio just became overly sensitive, which is also not very good.

    Close-up - the result of the work:


    The new antenna is also fixed with a heat shrink tube, as a result, the result is completely similar to factory products.

    If there is no heat shrinkage, you can tighten it with electrical tape. The main thing is that the plastic compresses the new antenna and does not allow it to move relative to the soldering, then it does not solder.

    In the general case, we do not touch the molulation. If one walkie-talkie receives a signal quieter than the other, then this circuit can be adjusted with a non-inductive screwdriver.

    To do this, set the max. volume on the adjustable walkie-talkie, remove the back cover, press the PTT on the second walkie-talkie and, bringing the second walkie-talkie, achieve a slight whistle from the first (configurable).

    Then, turning the contour on the adjustable radio, we achieve the maximum volume of the whistle. That's all for modulation.

    It is generally better not to touch the frequency capacitor without normal devices. For those who have a frequency meter, it makes no sense to explain what and how to do in this article, they can handle it themselves, the rest are better off just not twisting it.

    After resoldering the antenna, my field indicator at the same distance from the standard factory spring deviated about 4 times weaker than from the alteration.

    The range in the past alterations I increased by about 2 times. Good luck.

    If you need communication in a group over short distances of 1-3 km, then it is not at all necessary to purchase expensive radio stations. You can limit yourself to buying entry-level walkie-talkies. One of these is the Midland G5 radios, which I have owned for more than 2 years. Walkie-talkies were bought for communication in the countryside, for water trips, etc.

    Brief technical characteristics of Midland G5 radios

    Range: PMR - 446MHz

    Power: 0.5W

    Number of channels: 8

    Number of subtones: 38

    Nutrition: 3 AAA

    After active operation, a number of advantages and disadvantages were revealed. The advantages of the Midland G5 radio are its compactness, light weight and unpretentious operation. Despite its low cost, the G5 has solid reception, good receiver sensitivity and speech intelligibility comparable to more expensive models. Nevertheless, high requirements for radios of this type should not be presented. Midland G5 performs the function of simple and affordable communication perfectly.

    In the article on choosing a radio station, I described in detail what radios are and what ranges are suitable for working in a particular area. The PMR range that the G5 operates on is not quite suitable for operation in dense forest areas. In the forest, even more expensive walkie-talkies will not show communication ranges above 0.5-1.5. For this, the 2-meter range, or CBS, is better suited. On the water, the G5 allows you to get communication ranges of several kilometers, and in the forest less than a kilometer.

    The radio has 8 channels, each with 38 CTCSS subtones. For example, if channel 5 is busy, you can switch to another channel, or to channel 5 with a subtone (1-38). A total of 304 virtual channels are obtained. Virtual, because there are still 8 of them, but the use of subtones expands their number to 304. I note that when you turn on the subcode, the communication range is reduced by about 10%. It is better to use a subcode when the air is dense, and it is impossible to work on the main channels.

    Standard charging goes to 2 radios at once, connects through the headset jack and charges the batteries for a very long time, especially if their capacity is 1000 mAh. Namely, it is better to use such ones, because those that come with a set of small capacity and poor quality. In standby mode, Midland G5 radios consume 15-29 mA, in receive mode 60 mA at maximum volume, in transmit mode 250 mA. If you get out in the field for a long time, then you need to be able to recharge, or take good alkaline batteries. Operating time G5 1-2 days with infrequent use.

    Of the additional features - display backlight, Roger beep (transmission end signal), volume control, button lock.


    Model G5 is very compact, fits in any pocket. There is a clip with which the walkie-talkie can be fastened to flint, or to equipment. In addition, I sewed a Cordura pouch with MOLLE fasteners for the G5.

    I consider food in the form of a standard AAA format to be an essential advantage. Only the AA format is better, but this is already the Midland G7. I was convinced many times that the more standard the food, the easier it is to get out in a non-standard situation. Finger and little finger batteries can, if necessary, be bought in almost any tent. But you will not be able to charge the built-in lithium-ion battery somewhere in the outback. Moreover, batteries have a limited lifespan, and when it has served its purpose, you can simply not buy a new one, or it will be comparable in cost to the price of a new product. Those. The life of the device ends with the life of the battery. Ordinary AAA and AA format accounts do not have such a drawback. Equipment should be versatile and easily duplicated.

    In two years of using the Midland G5 walkie-talkie, I found two drawbacks. The first, not very significant, is that the low battery indicator lights up a few seconds before it turns off. Therefore, you can indirectly predict the discharge of batteries from a dim screen when you turn on the transmission. And the second, quite significant - in the off state, the G5 consumes a current of 0.5mA. That is, you can’t leave batteries and accumulators in the radio for a week, they will be discharged to zero. At first, I did not guess why one of the three batteries always discharged to zero when the radio was stored for a long time in the off state. After I found out that the radio consumes these 0.5 mA, it became clear that the battery with the highest internal resistance was being discharged to zero.

    Therefore, if you turn off the radio for half a day or more, you need to pull out one battery, thereby breaking the power circuit. Not entirely critical, but inconvenient, because you have to store the battery separately, which can also be lost. I began to lay a piece of paper between one pole of the battery and the radio contact.

    In general, I am still satisfied with the Midland G5 walkie-talkie. It performs its main function of simple communication over short distances with a vengeance. In some respects, it is in no way inferior to older models. Now it seems to have been discontinued, but it is still on sale.



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