More and more mushroom and berry lovers prefer to get to remote cherished places, rich in the gifts of the forest, on their "steel horses". Having left the car somewhere under the lush crown of a tree they like, they are fond of “quiet hunting” so much that they sometimes lose their orientation “in time and space”. As a result, instead of the joy of communicating with nature, there is a tiresome search for a car left unattended.
The proposed bearing system eliminates all of the above problems. It is compact, reliable and simple, because it consists only of a home-made radio beacon and a direction finder itself, in the role of which it is acceptable ... any pocket VHF receiver with a built-in telescopic antenna.
There are conflicting requirements for a beacon transmitter. And their essence is to receive maximum radiation into the air at minimum power (to reduce battery discharge) and, therefore, achieve high "range" of the entire system.
The radiation power of the homemade device I propose is about 10 mW. The required range is achieved by using grounding and a long antenna in the form of an insulated wire that can be thrown onto the crown of a tall tree.
The radio beacon can also be used to guard the vehicle. For this, a swing sensor must be installed in the machine. When touching the car, the contacts of the shock-sensitive device will connect an additional capacitor to the sound generator, which will cause a change in the modulation frequency. A lower intermittent sound will be heard in the VHF “direction finder” receiver.
The design of the radio beacon - subunit For installation, I recommend using printed circuit boards made (as universal, addressed primarily to novice radio amateurs) in accordance with the recommendations published in the magazine "Modelist-Constructor".
Well, for those who do not have the opportunity to familiarize themselves with the above material, we briefly inform you that a printed circuit board with a simple configuration of conductive paths can be made using a cutter (made, for example, from an old hacksaw blade) and a transparent ruler with a rectangular protrusion. To do this, on a workpiece made of foil-clad plastic, all the necessary holes are drilled in advance for the terminals of radio components and a drawing of insulating grooves is reproduced with a pencil so that future printed conductors are segments of straight lines or simple rectangular elements.
Then, along these contours, using a ruler with a limiting protrusion, the foil layer is carefully cut with a cutter to the insulating base. In this case, the protrusion of the ruler is aligned with the end of the groove to prevent erroneous cutting.
And to create non-conductive places with a complex configuration on the board, you can use a soldering iron. With its slightly overheated sting (the temperature is selected empirically), the removed section of the foil is heated, followed by removing the copper layer with a knife and tweezers.
Coils L1, L2 - frameless. They are wound with a PEL-0.8 wire on a rod with a diameter of 6 mm. Each contains 8 turns. The L2 coil is tapped from the 4th turn.
Capacitor C7 - homemade. It is made from two twisted wires with a diameter of 0.2 mm and a length of about 30 mm. The required coupling coefficient of such a capacitor with the antenna is achieved by adjusting the capacitance by unwinding the "sheathing" wires.
The entire setting of the radio beacon is reduced, in fact, to setting the "quiescent current" of the transistor VT2 by adjusting the resistance of the resistor R5. Achieve that the magnitude of this current was 6 - 8 mA.
1 - insulator base; 2 - electronics "radio beacon"; 3 - load - inertial swing sensor; 4 - contact pin; 5 - contact elastic plate
Now about the second term of the bearing system. In the familiar to many sports radio direction finding ("fox hunting"), special receivers with a highly directional antenna are used. Making such devices at home is difficult. But in our case, this is not required. As noted earlier, any pocket VHF receiver with a built-in telescopic antenna is quite enough for a motorist-mushroom picker to determine the bearing to a radio beacon left in the car, which are offered by numerous manufactured goods kiosks and stalls at affordable prices.
If this receiver is oriented vertically with the deployed antenna, then the directional pattern of the latter in the horizontal plane will have the shape of a circle. When the antenna is horizontally positioned, instead of one circle, two appear, in the form of a "figure eight" Such a "radio compass" has two minima and, therefore, does not give an unambiguous answer which side of it the "fox" is (in our case, a homemade radio beacon). However, the above feature is not of particular importance for the mushroom picker who has adopted the above-considered bearing system for his arsenal. I know from myself: initially, the side that beckoned with a successful "quiet hunt" is easy to remember.
Aiming the receiver to the minimum signal is more accurate than to the maximum. Based on this, it is recommended that the mushroom picker adhere to the following tactics to find the bearing to the radio beacon (and therefore quickly search for an abandoned car): a) place the switched on VHF receiver with an extended antenna horizontally; b) by rotating such a "radio compass" in the horizontal plane, to achieve signal loss.
The receiver will then be oriented towards the radio beacon.
N. MARTYNYUK, Kobrin, Belarus
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I have compiled instructions for you on how to assemble a bug with your own hands. This bug circuit is not difficult to assemble, it consists of available parts and is powered by a 9 volt crown. The operating range is 200 or more, it all depends on the transistor used. I found the scheme on an American site, fully working and effective, proven!
Beetle scheme
Parts List:Resistors:
Capacitors:
Transistors:
Miscellanea:
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Location of parts on the board:
First, download the seal file and make a beetle board. Then solder all the parts into place, as shown in the photo above. The archive can be downloaded from the link at the end of the article.
Coil making:
Now you need to make a coil. To do this, take a bolt and wind 7-8 turns along the thread copper wire, with a diameter of 0.5-0.7 mm, then twist the finished coil from the bolt and solder it to the board.
The coil is in its place and our beetle is almost ready, all that remains is to deal with the power supply. For the convenience of using the beetle, I suggest installing it directly on the battery (crown). To do this, we need two crowns, one can be taken out of the used one, we will need to remove the power stamp from it and solder the wires from the board to it. See below how to do this. The second crown will power our circuit and serve as a beetle stand.
Installation of power stamps:
Well, we take a gun with glue or glue for it and glue the stamp to the board. Our bug is ready!
Tuning the radio bug:
To tune the beetle, take the receiver and tune it to the frequency in the aisles 87-108 MHz. Install the beetle on the crown, without touching the coil, use a screwdriver to slowly twist the trimmer capacitor until you hear feedback from the radio in the form of a tone signal. By the way, the beetle is also caught on the radio of a mobile phone, I even have an auto search for it, so try this option first. When tuning, the beetle and the receiver should be close, how to tune in to the sound, move them away from each other. That's it, the beetle is completely ready and set up!
Almost everyone is familiar with the navigation system. Gps helps to quickly and accurately determine the location of a specific object - a person, car, other means of transport or animals. The simplest beacon is inexpensive in the store, but the more powerful one hits the wallet a little. But why buy if you really do it yourself? From what and how those who wish now will find out.
Self-assembly of a gps beacon, what to do, how to proceed
ATTENTION! Found a completely simple way to reduce fuel consumption! Don't believe me? An auto mechanic with 15 years of experience also did not believe until he tried it. And now he saves 35,000 rubles a year on gasoline!
Every phone, car, computer of a modern type has a gps beacon. The program is convenient, simple, and most importantly productive. The location of any object with its help is determined instantly. Gps beacon, as an independent device, is popular among motorists and parents who constantly want to know where their child is, but not everyone is in a hurry to spend their money in the store for this device. For such frugal people, there are ideas that will help them build a gps tracking beacon on their own and at minimal cost. You can make a beacon for tracking with your own hands in several ways and it is about them that we will now talk about.
Cool smartphone owners will get tracking system for free and effortlessly
Each smartphone that has a built-in gps module can become a full-fledged beacon that a person can use to get the coordinates he needs. The whole technical point of creating such a lighthouse is as follows:
After these actions, the owner of the smartphone will be able to use his device not only for calls, entertainment and Internet access, but also to track the location of a particular object. In this simple way, the smartphone turns into a full-fledged gps beacon.
For the system to work correctly, the android device must have a version of at least 3.2, but it is better if it is at least 4.1.2. Tracking object data will be displayed on the phone in the form of SMS messages or points on google maps Maps.
How to mount a gps beacon with a less fancy mobile device
A phone that is slightly inferior to powerful mobile devices on the Android operating system too 
can be an excellent basis for a gps beacon. In order to assemble such a device with your own hands, you will need to buy something else and show your skills in handling technical devices. in addition to the phone, you will need to stock up on an adapter - this may be a broken charger, where the side of the connection with the phone has survived. You will also need to buy a GPS / GPRS module and receiver.
If all the elements of the future lighthouse are at hand, you need to stock up on tools - a knife, a soldering iron. The work must be done according to the following principle:
- the wires that are the basis of the cable for connecting to the phone must be stripped;
- they must be connected to the module or using a soldering iron;
- connect the system to the phone socket, which is intended for charging;
- turn on the receiver and try to configure the necessary parameters from the phone.
Such a gps beacon will send signals to the phone in the form of ordinary text messages, and if it is possible to open maps, it is easier to see the coordinates on them, because it will be easier to navigate in space and determine the specific location of the object.
It's easy to use such a lighthouse, but at home. The design will be inconvenient enough to carry or install in a car. This is an ideal option for those who are going to look after their loved ones and children from home.
Is it possible to make a lighthouse without a phone
Before answering the question of whether it is possible to make a gps beacon with your own hands without a phone, you should figure out what this device really is and what features it has. Gps beacon is a device that is mainly used to guard vehicles. Has a compact size, powered by charging. The system accurately determines the location of the object, but for its correct operation, a SIM card must be present inside the device. 
The latter fact makes it possible to understand that the work of the lighthouse without a SIM card is not possible. In this case, there are only two ways out of the situation - to buy a ready-made beacon in the store or to make it yourself using a mobile phone and additional components. If there is no SIM card, the system will not be able to perform the following actions:
- correct and timely signal transmission;
- registration of a new tracking object about displaying statements about it;
- connect to the internet - this is necessary for gps to work.
If a phone with the latest operating system and a powerful processor is used, it is enough to download a special application for it, and a simpler model requires additional elements to work in the gps beacon mode.
Advantages and disadvantages of a do-it-yourself gps beacon
Even technical devices bought in a store have a number of their advantages and disadvantages. If we talk about a self-made gps mock, then its positive aspects are as follows:
- the ability to quickly, without outside help and large financial investments, make a reliable tracking device;
- even if you have to buy additional little things to construct a lighthouse, it will come out much cheaper than in a store;
- in terms of functionality, such a device is in no way inferior to the beacons that were bought in the store.
A person will be able to use such a beacon for many years, and if any inaccuracies arise in the work, they can always be corrected.
A self-made beacon for a car has a number of drawbacks that make it inferior in popularity to the standard version purchased in a store. Especially these negative sides are tangible for car owners and are as follows:
- due to the design features of the system, it cannot be correctly placed in the car interior;
- a mobile device must be part of such a beacon, and the constant tracking process can create difficulties for mobile communications;
- the lighthouse consists of several elements connected to each other, and when the car moves, they may become disconnected from each other or wire breaks.
If a person plans to use a beacon for receiving gps data for his car, then it is better to buy this device in a store. When a tracking system is needed solely for home use, a DIY beacon is ideal. The frequent use of such systems for cars prompted the creators to opt for a compact monoblock design. If you make an analogue of a beacon with your own hands only with the help of a smartphone and a special program, you can use it for placement in a car. If the lighthouse is made of separate elements, it is better to leave it for home use.
Gps beacon will always help to search for cars or other moving objects. You can buy it in the store or create it yourself. It is worth deciding which option to choose, taking into account your own financial capabilities, the purpose for which the device will be used and soberly assess your communication skills with technical devices.
On the Internet, you can find a huge number of radio bug schemes. Some circuits are too complex and require tuning, others are supplied with scarce radio components, and still others do not work at all!
I bring to your attention a bug diagram that can be assembled by both an experienced radio amateur and a beginner in this business.
Let's take a look at this diagram:
Do not pay attention to the dotted line yet.
To make a bug, we need the following parts:
- VT1 - kt315 with any letter index (if you want to increase the range of the bug, it is better to use a microwave transistor, for example kt325 or kt368, the imported s9018 transistor is perfect);
- C1, C4 - 47 ... 68nf;
- C2, C3 - 10pf;
- R1 - 33 kOhm;
- R2 - 100 Ohm;
- Oscillatory circuit L1 - 8 turns of copper wire with a diameter of 0.3 ... 0.5 mm on the rod from the helium pen, wind it carefully, turn to turn (I evaporated the finished coil from the broken radio receiver).
- M1 is an electret or condenser microphone.
In order to save space, I used the right microphone (I found it in an old mobile phone). Despite its size, it turned out to be very sensitive.
All parts except L2 choke and microphone are shown in the following picture:
To make L2 we need a match and a very thin wire:
We measure one and a half centimeters of the match, bite them off - this piece will serve as the choke core. Next, we take the wire and wind one hundred turns. We fix the conclusions of the resulting coil, clean it of varnish, tinker. That's it, throttle L2 is ready!
When all the parts are assembled, you can start making the printed circuit board.
To do this, we need a piece of PCB 35x15mm and the solution itself in which we will etch the board (I used hydrogen peroxide + citric acid). We draw a drawing of a printed circuit board (I drew under the s9018 transistor)
and transfer it to textolite.
We put the board in the solution and wait until the excess copper disappears.
After the board is worn out, we take it out, rinse it with running water, remove the varnish and tinker it:
Next, we solder the parts in accordance with the diagram. Attention, when installing parts on the board, do not overheat them, otherwise they will fail! Be especially careful with VT1 installation.
I want to say a few words about connecting the antenna, the signal is supplied to it from the emitter of the transistor, which makes the operating frequency of the bug more stable.
Assembled diagram:
The bug can be powered in the range from 1.5 to 9 volts.
Any of these batteries will power the circuit. I used a AAA finger battery to make the bug more compact. You can also use a 3-volt "pill".
If you will power the circuit from the crown (9 volts), then you should include a 100 Ohm resistor R3 in the circuit.
Gently solder the battery to the bug. An insulated wire 30 cm long can be used as an antenna, but practice has shown that its absence will not greatly affect the reception range of the circuit. That's it, the bug is ready!
Now we turn on the radio and look for the frequency of our bug. The signal from it can be caught at a frequency within 88-108 MHz. For me this frequency was 92.2 MHz. If the bug "does not communicate", then try to move the turns of the coil L1 apart - this should help solve the problem.
With a supply voltage of 1.5 volts, the reception range is 30 meters, if the voltage is increased to 3 volts, then the reception range will increase to 100 meters.
This circuit also has another application - an audio transmitter. Let's say you need to output sound from your phone to a tape recorder, but the latter does not have an audio input function. No problem! In this situation, this scheme is very useful. Almost all tape recorders have a radio reception function (FM radio), then we will use it. Remember the dotted line on the bug diagram? We exclude the M1 microphone from the circuit, connect the capacitor C5 to a capacity of 10μF, connect the 3.5mm mini-jack plug to the minus of the capacitor and the minus of the power supply (minus the jack to the common, left / right to the minus of the capacitor) and transmit the sound from the phone to any radio receiver within the range of the transmitter! With the correct assembly of the parts, the circuit starts working immediately.
These products can be used for a variety of purposes: from listening to rooms and to wireless transmission sound.
And on this my article comes to an end, good luck to everyone in repetition!
The circuit is very simple and is designed to be built by teapots. It is used to track the movement of various objects. You need to look for it with a directional receiver, which will be discussed in one of the following articles.
We see terrifying simplicity. On the first two transistors, a multivibrator is assembled, the frequency of which depends on the resistors and capacitors, that is, having played with them, it can be easily changed. For ease of perception, they usually take about 1000Hz. Further, a simple and reliable generator circuit with a common base. This circuit has been repeatedly assembled in bugs, and has an indisputable guarantee of operation.
The frequency depends on the inductance of the coil. If you want to make a buzzer for the broadcasting FM band, then the first coil is 6 turns of 0.5 wire on a diameter of 3mm, a classic. The second - 4 turns are located nearby. A capacitor of about 10pF can be connected between the antenna and the coil. I recommend taking frequencies around 120MHz, this is dictated by the greater efficiency with a smaller antenna.
The antenna is not quite standard. Consists of 3 pieces of coaxial cable with removed braids, between which there are extension coils. We make coils by eye. The total length with the unwound spools should be about 30cm. If a short range is meant, about 20-30 meters, you can leave one piece 10-15 cm long.
Transistors are used - the first two are practically any, with a satisfactory gain. The third - any, with a frequency of at least 100 MHz. BC547 worked fine for me.
Power supply - 5-15V, when power supply is more than 10V, it is necessary to increase the resistor in the emitter circuit of the third transistor to 150 Ohm. You can use a crown, or 2 batteries from a mobile. Range with a normal receiver 200-300 meters.
List of radioelements
| Designation | A type | Denomination | amount | Note | Score | My notebook |
|---|---|---|---|---|---|---|
| Bipolar transistor | BC547 | 3 | Into notepad | |||
| C1, C2 | Capacitor | 0.1 uF | 2 | Into notepad | ||
| C3 | Capacitor | 1 uF | 1 | Into notepad | ||
| C4 | Capacitor | 0.01 μF | 1 | Into notepad | ||
| C5 | Capacitor | 30 pF | 1 | Into notepad | ||
| C6 | Capacitor | 12 pF | 1 | Into notepad | ||
| C7, C8 | Capacitor | 56 pF | 2 | Into notepad | ||
| R1, R3 | Resistor | 560 k Ohm | 2 | Into notepad | ||
| R2, R4 | Resistor | 20 kΩ | 2 | Into notepad | ||
| R5 | Resistor | 15 kΩ | 1 | Into notepad | ||
| R6 | Resistor | 10 kΩ | 1 | Into notepad | ||
| R7 | Resistor | 3 kΩ | 1 | Into notepad | ||
| R8 | Resistor |