Good day! In this post I want to share with the Internet community on how I happened to make a automatic light on the stairs in his two story cottage. About four months ago, returning from work in the dark, I successfully slipped and broke two pljusnevyh bone (finger) on his left foot. A whole month had fail in bed, so as to step on the foot was incredibly painful. Then another half of the month was lame without plaster (who had fractures, I’ll understand). After this sad story, I began to think about automating the lighting of the stairs. A bit of tinkering with the search query found a very simple solution in this blog, just based on my favorite Arduino microcontroller. The scheme did not cause any difficulties, but was baffled by the number and length of the wires that I had to mount. Prior to that, did nothing of the sort. To buy ready decisions, or to hire someone is expensive.
Ham radio
CONDENSER FLASHLIGHT
In the memorable 1990-e years I worked at the Kirov plant instrument maintenance computer. Every morning we had to go down to the basement to enable refrigeration. Bulbs in the basement then disappeared, burned out. In short, as a rule, to see the switch, had to use matches: even to buy a flashlight for the plant was the problem. Then appeared the idea to make such a lamp yourself. From the power supply batteries and battery items I refused: they often fail, leak or anything. I did almost “eternal” condenser flashlight.
ELECTROSHOCK FOR SELF DEFENSE
Among the means of self-defense e-treskovye device (ASH) – not in last place, especially the strength of psychological impact on criminals. However, the costs are considerable, which encourages radio Amateurs to create homemade analogues (detailed material about it see, for example, in No. 5,’99 the magazine “modelist-Konstruktor”.
Without pretending to sverhordinarnogo and Superviso ideas, suggest their own development, to repeat which is able to anyone who at least once in their life has dealt with the winding of the transformer and installation of simple devices like crystal radio with an amplifier on one or two transistors.
THE SOUND WILL BE LOUDER
In order to obtain a sound signal of high power (10 – 20W) from the simple Assembly of a sound generator, does not require complex amplifiers WOOFER.
The generator on the popular chip KP1006BU1 (DA1) is enabled by almost classical scheme and in the description is not needed. The output frequency is approximately 1000 Hz. It can be considerably corrected by changing the values of the elements C2 and R2. The output frequency in this circuit is calculated by the formula:
F(kHz) = 1,44/(R1 +2xR2)xC2, where the resistance of the resistors R1, R2 in ohms, and the capacitance of the capacitor C1 is in microfarads.
“RAZLAGALSA” BATTERY
On the recommendation of the manufacturer to eliminate the memory effect of Nickel-cadmium batteries (NiCd) should clear their element to 0.4 V. For the implementation of the above requirements and automate the process of disconnecting the battery reaches level 0.4 V the authors propose a simple device.
To reduce the disconnection threshold of the discharge transistor /T2 is selected with a high rate of current transfer. The load (in addition to the resistor R2) and at the same time an indicator is incandescent НL with a voltage of 1 V at a current of 75 mA. In the absence of a low-voltage light bulbs a consumer may be led АЛ307Б.
MAGNETIC PROBE WITH ALARM
Of the readers who didn’t lose metal parts or tools? Sometimes it happens at the most inopportune time and threatens to permanently stop work. Lost somewhere in the grass screwdriver that fell behind the Cabinet chisel or a failure in a pier of pliers is able to ruffle anyone. In such cases a simple device – a magnetic probe with light and sound alarm. Using this simple device, you can easily find the loss in hard to reach places and the fact findings you will be notified outbreak warning led and buzzer. The principle of operation of the probe is quite simple – on a long rod fixed two magnet “sticking” to the metal object which closes the circuit and lights the warning led. Thus, you can know when the probe with discovery, you can extract the “light”.
B-25 Mitchell Bomber
RC replica model in 1/9 scale American bomber during the Second World war. Model made from balsa and plywood construction designed for use with internal combustion engines.
REED SECURITY — SIMPLY AND EFFICIENTLY
Security systems are a rapidly developing area of modern electronics. Published a huge number of various schemes and designs that can make anyone a couple of times was holding the soldering iron. For example, “electronic security guards” can warn of an intruder enters the premises or to signal the presence of the recorder for unauthorized sound recordings.
Porsche 911 GT3 RSR
All-wheel drive R / C model Porsche 911 GT3 RSR on the chassis of the entry-level Fazer. Chassis Fazer is equipped with an internal combustion engine Kyosho nitro type GF-16SG and a fully installed and configured radio system Kyosho Perfex/Futaba KT-6.
THE FUSE IN THE AC CIRCUIT
Circuit of electronic fuse alternating current, represented in the figure, protects the circuit in which the output is regulated by the triac (or just the triac operates in the mode “connect – disconnect”) by removal of the control signals when current exceeding the specified value (emergency operation).