In the last package from the American Amazon came the Ambient Weather WR-111B Radio. The tuner is digital, but the channels do not remember. FM (not extended) and AM bands are supported. A weather band is also supported, and there are sound and visual warnings, but such a service is unlikely to be relevant somewhere outside the United States.
This radio is intended primarily for use in situations where there is no electricity. This can be banal shutdowns, including due to the fault of the raging elements. It is also suitable for outdoor activities. The design hints at the latter, as well as the rather tight buttons. It is easy to take it on the road due to its light weight - less than 250 grams.
On the left side of the radio is a flashlight (3 LEDs, 15 lumens). On the right side, there is a headphone jack, a power adapter and a USB charging output (included are adapters for charging smartphones, tablets, e-books, ... via Micro USB and Mini USB). Including thanks to the purchased adapter with MicroUSB, I had no problems with recharging the Apple iPhone 4s.
You can charge the radio receiver battery from the mains. Also on top of the radio is a solar panel. The manufacturer claims that direct sunlight is enough to listen to the radio. At the same time, the early spring sun in the apartment is not enough for this.
Most smartphones now have batteries of 1000-2000 mAh or more. To charge a 1500 mAh battery from the sun, it will take about a day of good daytime sun in central Russia. But since the solar intensity varies greatly during the day, and also due to cloudiness, it will take several days to fully charge the smartphone from the sun.
The receiver has the ability to manually charge (dynamo). If you turn the knob for 1 minute, then, according to the manufacturer, you can listen to the radio at an average volume for 20 minutes. The handle can be turned at a speed of no more than two revolutions per second, taking breaks every two minutes.
I took the option on Amazon without a power supply, since the radio uses a regular power supply with a 5V / 0.5A Mini USB connector. You can also charge the radio from a computer, just use a USB-MiniUSB cable.
The battery is powered by a CR123A 3.7V 800 mAh battery. This is not some kind of own development, so you can replace the battery without problems.
A fully charged battery lasts for 350 minutes of listening to the radio at medium volume. The small capacity of the battery, of course, implies only incomplete recharging of mobile devices. But in a critical situation, the energy of the sun and manual recharging can greatly help out, especially if you are far from civilization, or the electricity is turned off.
This radio also has cheaper counterparts, but after comparing reviews, I settled on this particular model. Reviews on Amazon for Ambient Weather WR-111B 4 stars out of 5 (more than 1300 reviews). At the same time, negative reviews are often caused by a lack of understanding of how well you can charge the battery with the help of the sun and a dynamo, how long you can listen to the radio, devices of what power, with what connectors and how much you can and should charge using this 3 in 1 device.
I was very pleased with the reception quality of FM radio stations, even with the antenna folded. There are stations in Rostov using automatic search without problems. The sound quality corresponds to the miniature of the device. Assembly and quality of materials at a good level. It will be necessary to test it in the summer sun.
(Update)
As a budget alternative, the Emergency AM/FM/WX Crank Radio 20-576 with Ni-Mh battery, dynamo, but no solar is available on Amazon today for just $13 (versus $35 for the Ambient Weather WR-111B).
Operating frequency - 100 kHz. I tried 200 kHz - it didn’t get any better, and it’s easier for key field workers (and IR2153 too) to work at 100 kHz. An important element of the circuit is the capacitor C4, with which the coil L3 forms a parallel oscillatory circuit. The coil contains only 7 turns of 1 mm wire, and without this capacitor, much more turns would have to be wound, reducing the diameter of the wire to fit into our dimensions, as a result of which there is more loss for heating the wire, since even with a 1 mm wire the coil heats up quite strongly . Yes, and the required current without this capacitor cannot be obtained.
Resistor R2 is needed to adjust the frequency so as not to select capacitor C4. As a result, by changing the frequency, we change the output current of the circuit. This is necessary to set the desired current. Through 3mm plastic, memory capable transmit current 1A, but at the same time the coils get very hot (much stronger than transistors). Better expose about 0.5 A.
Charger Transmitter:
Coils wound on a collapsible plastic bobbin 2 mm thick:
I wound the receiving one without one side cover, laying a piece of paper under it and impregnating it with superglue in the process. The transmitter was impregnated with varnish or rubber glue - which was at hand. But since it will get very hot during operation, it is better to fill it with epoxy.
charge controller use from Eddy71, but you can also put TL431 + LM317 or, in general, a dead battery protection board. Or take a battery with a built-in charge controller. It’s just that the controller that I use not only charges, but also prevents the battery from discharging below 3.1 Volts, and a tact button is connected to it, which allows you to turn on / off the load.
Power supply for wireless charging I used 12 Volt 2 Amperes, it costs 5 bucks, but inside there is a PWM controller and a field switch on the radiator. There is even a network filter, which pleased me. This is not a cheap simple electronic transformer.
My favorite mobile phone NOKIA 6500, which was bought about six months ago, was not initially charged. Repair work was carried out, after which the phone worked for about a month. The main problem was that the phone had to be charged using a universal charger, and it was inconvenient to constantly remove the battery.
It was in connection with this that I decided to install a wireless charging system on the phone. The system was assembled according to my own idea within a couple of hours.
How wireless charging works
The principle of operation of such a wireless charging circuit is quite simple. The role of the charger is played by the transmitting circuit, the device itself consists of two circuits - a transmitter and a receiver.
The receiving circuit (flat coil) is located in the phone itself, the transmitter is made in the form of a small stand, inside of which the transmitting coil is hidden.
Wireless Charging Diagram
Electricity is transferred from one circuit to another by induction, the current that has arisen in the second circuit is first rectified and fed to the battery. Literally any low-power Schottky diode can be used as a rectifier.
Let's start assembling wireless charging with our own hands from the transmitter.
Transmitter
The transmitter circuit is simple and clear. The usual blocking oscillator circuit on a single transistor. The frame for winding the transmitting coil is at your discretion. It is advisable to take a frame with a diameter of 7-10 cm. We wind 40 turns of copper wire with a diameter of 0.5 mm onto the frame. The winding has a tap from the middle. First, carefully wind 20 turns, then twist the wire, make a tap and wind the remaining 20 turns in the same direction. Is everything clear with the coil? Let's move on.
Absolutely any transistor, I tried both field and bipolar ones, with field ones it charges a little faster. You can use field keys of the IRFZ44 / 48, IRL3705, IRF3205 series (I indicate only those that I used myself), but you can literally set any. Of the bipolar ones, domestic ones can be used: KT819, 805, 817, 815, 829. The choice is not critical. You can also use direct conduction transistors, but in this case you will have to change the polarity of the power supply.
The value of the base resistor is not critical (22 Ohm-830 Ohm).
Receiver
The receiving circuit - shook for half an hour. The coil is flat, consists of 25 turns of wire 0.3-0.4 mm. It is convenient to wind the contour on a small piece of plastic, the turns need to be gradually strengthened with superglue, the work is quite dirty and long. After winding, we separate the circuit from the plastic stand on which it was wound. It is convenient to do this with a mounting knife or blade.
In my case, the charging connector on the phone did not work, so I connected the charger directly to the battery. This solution is inconvenient because the sensor will not show that the phone is charging. Everything is completed with the phone, now you need to put the back cover.
Charging time directly depends on the power of the power source, in my case, the factory charger of the experimental phone was used. The device provides an output voltage of 5V, at a current of 350mA.
Such a wireless charger for the phone works flawlessly, with this arrangement of components, the mobile phone is fully charged in 7 hours, a long time, but it is charging. You can speed up the charging time only by strengthening the circuit - use a more powerful power supply and wind the circuit with a thicker wire.
Let me tell you, don't buy from this store! it will be very expensive, we are looking for it on eBay and others like them ...
Purpose of purchase: I liked the hypothetical opportunity not only not to depend on batteries in nature, but also to charge available gadgets!
Plus, the old "marching" died from "on a grand scale for crappy personal qualities."
Expectations were rather "ghostly" ... But when I received the package, I was pleasantly surprised! Let's just say VERY NICE!
Packaging: a solid box, like all Chinese colorful and cheerful.
Appearance:
Completeness:
the receiver itself, headphones (UG but for “immediately out of the box” it will go), instructions (neither a power supply, nor a cord for charging devices, nor adapters to a cord).
And so in order:
The receiver turned out to be surprisingly small. I expected large sizes, assembly and quality of materials used for sure 5! I was a little shocked! If the manufacturer was, what kind of thread is "grundik", I would believe it! Nothing staggers, creaks, or flops when shaking, there are no crooked stencil inscriptions, the plastic is pleasant to the touch! It is possible to carry on a belt - fasteners are built into the handles, but there is no belt ...
Now about the operation of the receiver ...
Charger:
Right out of the box I put it on the windowsill (without batteries) and turned it on, the diode signaling the charging process lit up and the receiver sang! The solar battery worked and it pleased! Then I twisted the handle of the dynamo machine, the effect is the same! The dynamo is running and charging the internal battery!
Reception:
The receiver catches everything in the specified ranges, the reception is good, there is a diode signaling fine tuning to the station! But the selectivity is at an average level ... sometimes the stations crawl into each other (((
FM reception is confident even 57 km from the city in the forest.
FREQUENCIES:
SW1
4.0-9.0MHz
SW2
9.0-14.0MHz
SW3
14.0-19.0MHz
SW4
19.0-26.0MHz
MW
520 ~ 1720 kHz
FM
87~108MHz
FML
64~87MHz
Other features:
-The receiver can work like a regular flashlight (at the end there is a diode under the lens) - oddly enough, it shines quite brightly and allows you not to stumble on a forest path at night! (verified).
- The receiver can work as a table lamp! 3 diodes are built into the receiver handle.
They don’t give away blue, they illuminate the shift table, you can confidently read the newspaper on the table!
- The receiver works as an emergency beacon - in this mode, the receiver beeps loudly with an “alarm”, accompanying unpleasant sounds with a red flashing of the end diode of the lantern, you can hear it for 200 meters in the forest! You can see 50 meters at night.
- The receiver charges third-party connected devices! There is a way out for this, we buy a lace and adapters separately! We turn the handle of the car dynamo - Nokia accepts charging, don’t ask how much to turn for a full charge))) but 3 minutes was enough to talk for 2 minutes))
The solar battery provides charging for the noka of current in bright sunlight ....
Internal batteries do not allow the receiver to charge anything (((for an autopsy showed that they are 360 mahs in total, with a voltage of 3.7v. but I immediately castrated and replaced this under-battery with banks with a capacity of 2 to 1100 mahs, there is enough space inside the receiver for creativity))
After replacing the internal battery, it is enough for me to listen to FM stations for 5-6 days (charged from the mains) and for a day from standing on the windowsill during the day! Plus, it became possible to drain about 80% of the charge into the communicator during the night, while sleeping in the communicator, from the battery capacity of the communicator (1500 mach) and at the same time continues to sing and work like a lantern in the morning!
Receiver Power:
Accordingly, this device is powered by a built-in battery, plus it is possible to insert 3 AA batteries (enough for 5 days), plus there is a connector for external power supply (the unit is purchased separately).
Listening experience:
The receiver produces a good clear, no rattling, loud sound, but there is also a stereo headphone jack.
Lyrics:
This device really impressed me both with the quality of performance and the work of all the declared functions! With the exception of the built-in battery, or rather its capacity.
I strongly recommend for purchase to tourists - fishermen and just to the dacha - the village, it will help out in case of a sudden blackout. Saves space on a separate flashlight and travel charger)))
Dreams: the only thing I would add to the function of the device is the ability to connect an external sound source (player phone), which I actually try to solve by unraveling the printed circuit board and making changes with setting the mode switch and input.
Or (a very fat dream) - playing flash drives ... well, an alarm clock would not hurt with a coffee maker and a toaster))))
