Among the many toys in the electronics, is able to mimic the sounds of animals, is very amusing. For example, a toy cow, imitating mooing, or a pig, saying, “let’s Go home, I’m hungry!” The first mentioned industrial products, presentable shaped like miniature soft toys (manufacture of our neighbors from China), electronic device emits a sound “mu-u-u” that can be used for a variety of fun devices, adapting a toy, for example, charm signal in the car.
When there are dynamic microphone, you can substitute any small-sized dynamic head. Here’s what proposes to make to the Yugoslav magazine “Radio Amater”. Since the voltage developed by the head, a little, pre-amplify with low-yield of germanium, for example, МП39— МП42, or silicon (KT361, КТ203, КТ104) of the transistor included in the scheme with a Read more…
DEVICE FOR CHARGING BATTERIES is a rectifier device with electronic current regulator (Fig. 1). A rectifier manufactured by bridge circuit of diodes V1 — V4 (Fig. 2), and the electronic controller a current amplifier transistor V5. The necessary adjustment select using the divider resistors R2, RZ, providing current from 4 to 6 And at a voltage of 8-15 V.
The ham-hams is well known that, to ensure reliable connection in addition high-sensitivity receiver and a powerful transmitter is needed and a well-designed antenna. There are many types of antennas, however, have to limit ourselves to just two or three. And one of them often becomes a quarter-wave vertical pin or, more precisely, its improved version, which in radio is called the Ground Plane.
When the firebox of the fireplace or stoves in the country wood raw material to the combustion process from time to time it is necessary to control: throw the wood, increase craving, etc. to Replace “master’s eye” and recall this can offer an electronic device indicating the reducing flame in the furnace (the furnace).
In the process of operation acid batteries gradually sulfation of the plates which reduce capacity and shorten the life of the device. To eliminate this undesirable phenomenon, a special rectifier. The device is intended for use in stationary and field of auto repair shops. Collect it, you the driver with basic knowledge in electrical and electronics.
Flashing beacons are used in electronic home security systems and in cars as devices of indication, alarm and warning. Moreover, their appearance and “stuffing” are often not distinguished from beacons (special signals) emergency and operational services.
Change arrow indicators the dog often come led. And this is not surprising: the second is much easier and safer first. Simple five-level scheme of the AF voltmeter to the voltage of 0.1—0.6 volts, where the indicators are LEDs, published in the journal “Рипката1ег” (GDR). If the signal fed into socket x2, XS, the voltage exceeds 0.1 V, open transistors V2, V4 and, as a result, the led turns on Q1. With an increase of the signal to 0.2 In open semiconductor triode V6 and the led flashes B2. When the signal voltage reaches about 0.6 V, burn all the LEDs.
After a few years of correct operation your drill is the drill started to “MOPE” – ends quickly charge the battery (battery), has to be frequently charged, and for this to interrupt your work. Losing battery capacity is inevitable with heavy use (depends on the amount of discharges-charges) and over time. By the way, if the drill is rarely used, the battery capacity is also reduced by itself (especially if it is stored uncharged), and a year later, may be reduced by a quarter or more. But in many cases, this occurs prematurely because battery other dangers face. So, it will inevitably deteriorate if you apply the tool when the ambient temperature is below 0°C and above +50 °C and in rainy weather and damp conditions, especially if spilled into the water.
Observance of measures of fire safety is necessary for everyone, always and everywhere: at work, at home. And if the companies behind this control is performed by fire supervision bodies, in houses — all this, entirely, entrusted to the tenants.