Small disk batteries are widely used in electronic equipment and in ham radio construction. But to charge them is not easy. Then stir and pure design features: the differences in the size of the disk batteries, no special conclusions for reliable connection to the external circuit and connectors between the individual elements in the batteries. In addition, it is necessary to control the magnitude of charging voltage and current using electrical appliances.
CHARGING AND RECOVERY DEVICE’S BATTERY. The battery in the car is one of the most important elements. Despite the constant efforts of manufacturers to improve the reliability and durability of the batteries after 3 — 4 years they still come into disrepair, aided by a constant undercharge when riding in urban environments the cost of the battery remains high, so to extend the term of its service makes sense at least once in the summer season to carry out remedial exercises.
Usually automatic device switch on and off the Christmas tree lights in leaps and bounds, without changing the brightness. But the electronic switch scheme is presented in figure — does not have this drawback. The basis of his work is based on the principle of beats that occur between the frequencies of the mains and generator. The latter is a multivibrator transistors T1, T2. It generates rectangular pulses with a frequency of (100 ± Δ) Hz (100 Hz is the fundamental frequency of the multivibrator, And the frequency of the beating, which switch lamp garland which is in the range of 0.1—8 Hz). Adjustment of the burning time of the lamps is variable resistor R6 “Smoothly” and R7 “Rough”.
The light on the dash must have heard many. A pistol or shotgun just like the real thing, the rings of a target with a ten in the middle. Yes, but “bullets” are not the same. Pulled the trigger and the target affects short flash of light. And the brighter dalnoboynie weapon. The light beam of the flash lamp to “shoot” at a target even from a distance of 25 m. This corresponds to one of the distances sports bullet shooting.
This switch Christmas garlands periodically includes four groups of lamps. The switching frequency can be changed within wide limits by the variable resistor R5 (see diagram).
Simple dual-band receiver of direct amplification on a hybrid chip К237ХА2 can collect even a novice hobbyist. Moreover, the sensitivity and selectivity it even higher than the equivalent discrete components. And to make it easy.
Probably you happen to see this picture: all the appliances in the apartment turned off, and the meter disk rotates slowly. It turns out that the culprit door electric bell: its primary winding permanently connected to the network.
In the design of devices and equipment before the radio often question about their design: sometimes they place boards and panels of their devices in boxes that slides, fishing gear and other containers. Ham D. Plewinski offers as buildings to use more modern products — cases videokasset: they have a low cost; plastic from which they are made, can be easily processed.
Revision of power supply EPS-35. Every radio Amateur, equipping a workplace, in its own way solves the problem of providing it with power supply (SP). Some prefer powerful UI with an output current 10 and 20 a, And someone is satisfied with a simple and low-current (up to 2). The taste and color, as they say, no friends. From my point of view, home laboratories should have a SP with output current not less than 5 and the overload protection on the output.
Usually they work, if it is correct to type the code on the keypad. Electric locks, which are placed in this article, operate on a different principle. The key for them is a small socket with the pins, for example, finger lamp. Socket is the base — it installed schema key. When enabled, a lock is triggered. And, as we have commotional lead wires, to reveal the secret of the castle will not succeed.