No special requirements were put forward for the transistor, it just got caught first in the cassette and turned out to be acceptable in terms of parameters: collector current up to 10A, base current up to 3A, collector-emitter voltage 600V, gain at least 20. To generate the signal, Arduino Nano was used with the program "Terminal version of the generator" comrade. dimax from here

Frequency response of photocell and TEMT6000

To measure the output signal of the photopanel, an ordinary multimeter was used in the AC voltage measurement mode. The emitting diode was placed above the photopanel and the whole structure was covered with a box to eliminate the influence of external stray lighting. It always seemed to me intuitively that the use of a photocell from a cheap garden lamp would not allow us to investigate the spectrum of lamp pulsations sufficiently. Recently, while sorting through the rubbish on the balcony, I came across a photo panel from some kind of power bank. The output signal of the oscillator (meander) was fed from leg D9 to the base of the transistor. Here the thought arose – should I measure the frequency response of this thing? 🙂 The results were entered into Excel, a graph was built: More than once in the discussions of devices for measuring light pulsations, I came across statements like “why use high-quality and high-speed photodiodes when it is enough to take a photocell from a garden lamp!” Next, the generation frequency was set from the keyboard and the output signal was taken from the photopanel. To illuminate the panel, a red LED was used, powered by a pulse generator on an Arduino Nano through a KT854A. A red LED with a 470 ohm limiting resistor was included in the collector circuit. A simple stand was built to measure the frequency response.

Voltage Power 4.2-5.5V Next, the machine waits for commands from the PC

Also attached materials for testing Field of use engraving, hand tools and industrial processing Laser power< /b> 1000mw The front window is closed with a green protective plastic filter on two magnets for quick assembly and dismantling.

Appearance: There is also a dad to power the 5W laser and
above. Thus, you can load a picture into the machine and print already a number of copies of repeating layouts already in another place, for example, in a ventilated room. On the table of the machine is attached a sample of printing on this machine where you can immediately evaluate the quality of printing and the size of the working area
The machine came in a cardboard box with inscriptions in several languages, including Russian. CAN NOT Engrave Metal, Aluminum, Acrylic
Below are the samples printed on this engraving machine, it turns out well, as for me, with this size of the working area – print quality excellent, draws fine details clearly, burns wood for at least 10 ms. plastic from 50 ms, transparent acrylic from 100 ms.
It immediately goes through initialization and calibration from edge to edge. Such an engraver served as a visual aid for applicants and an advertisement for our specialty. Model DК-8-KZ Net weight 1100G It can be changed directly in the process of burning, burning can be paused or canceled. You can set the number of passes for a given pattern.
Laser wavelength 405nm When you press it, the laser draws a work area on the material and press it again to print the last picture loaded into it without a computer. 2 * USB cable The power input itself is marked at 5V 3A, from which we can conclude that it is possible to connect a laser of about 10-15W.
Drag the image to the application, cut off what needs to be applied to the material, set the overall dimensions and then select the engraving method, with shades of gray, with a contour or just black and white. This was available in previous models, here for some reason it was sent to a hidden place.
The board has additional connectors for older models with bluetooth and powerbank.
Removing transport. film from the filter and install on the machine But first things first.
All moving parts are immobilized during transportation with protective tapes and pieces of polyethylene foam, which is removed before use The printing software is a self-sufficient executable, clicked, started, found the port of the included engraver and is ready to use The engraver is connected to the PC with two USB ports, on the other end of the connector 5.5×2.1 mm to 5V and USB type B / On top, the red button turns on the engraver. Machine size 19.8×14.5x16cm 1 * green piece of plastic for focusing

Power Current 1A Specifications: The driver is installed in one click (Usb serial) 1 * User Manual
Let’s disassemble the machine and look at the control board and the laser. We also discovered a hidden button that does a curious thing. Image size 490x490pixels I work in the field of education, I teach students computer-aided design systems and indirectly work on machine tools, including CNC. Go to the NEJE website and download the driver and print program. Screenshots of the application workspace are shown below, everything is quite simple. Raster engraving Can engrave Mahogany, bamboo, paper cards, ivory, leather, flammable plastic, PCBA, etc.
Consumption of the machine is about one ampere on both channels in total Image formats JPG

NEJE DK-8-KZ 1000mW 1W laser engraving machine for home and educational purposes.

5 * various burn test materials (cardboard, plywood, fiberboard, sandwich panel) In the settings you can set the brightness of the laser in standby mode The body of the machine is made of black acrylic with windows for setting the part and monitoring the process.

There is a fan on top to remove combustion products during the engraving process
At the bottom there is a laser intensity slider from 1ms to 100ms. 1 * lathe Laser operating temperature 500 degrees 1 * green plastic protective sheet The choice of this device was due to the specifics of my profession.
There is also an online gallery of pictures and a tutorial on how to work Working area 38 * 38mm
After that, we position the image on the material using the buttons on the application panel. In the box there is a machine in films and a small box with wires and other things, namely: Material Acrylic aluminum stainless steel 1 * hex wrench Healthy.

Brand NEJE Pressing again pauses printing.

The notepad is distinguished by the fact that it closes with a lace on which a leaf is attached, the leaf itself is made of metal and painted with golden paint. There was rubbish inside, looking closely, it was pieces of paper, so to speak, waste products.

Vintage notebook

Too lazy to read, watch the video review. On the top cover there is embossing in the form of leaflets. The cover of the notebook resembles the surface of the skin, the inside is velvety. Sheets can be cut out of plain paper of any color. Dimensions 10.5 x 14.8 x 20 cm The package arrived quickly, but the packaging did not please me, two packages were all that protected the notebook from external influences, I ordered a notebook with a track number. Good day, quite recently, or rather in the last 2015, a similar notebook was reviewed, you can read it by clicking on the link the author of the STANOK review. Paper, an ordinary pen glides easily, minus the holes are not neatly perforated, but if it is a vintage notebook, then such paper processing for the general style is quite suitable. The paper is attached with metal staples. A lace tied to a leaf resembles leather in structure.

It was always interesting to study the diagrams of Professional class products. In my own practice, I don’t use such BPU-301 devices, due to their high cost. I will not particularly describe the device, whoever is interested in the network will find an overview of it. The manufacturer positions this power supply unit (PSU) as a professional one, therefore it costs significantly more than its cheap counterparts at 300W. And here such luck. The case of this PSU is made of thick-walled (3mm), specialized for a low profile, aluminum profile. Naturally, I did not buy this PSU to answer these questions … it will still fall into my hands for nothing … By the way, he also, not a bastard, (after all, like me, a professional electrician) tried to study the issue, call there … a fuse, a diode bridge, primary circuits are shorter for breakage or breakdown, but … unsuccessfully.

Autopsy and primary diagnostics I paid attention to the “professional” PSU from Biom relatively recently, when models that were interesting in terms of size ratio came into my field of vision, for example, this elongated 60W Not at all! here it is conservative – MeanWell (they have a large selection and the best prices in their segment). I’m interested in how it works and how it works. It became interesting what kind of there is a transformer, what is the topology of the converter, and so on. Device and repair

This combination of components is optimal for restoring some 36W LED panels. (I’ll tell you about this separately) As always, such devices are brought by friends. Good afternoon colleagues and friends! To restore raster LED lamps from him, I purchase a powerful LED strip BPS-G3-12-2835-120-CW-20, an economy class budget power supply unit TR-60-12V (the schematic of which is here) Doesn’t work when turned on. The other day, I got my hands on a "300" power supply BPU-301 for 12V / 25A from Biom.

Biom Professional BPU-301 power supply. More often it turns out to get by with more affordable power supplies of the same Bioma only economy class, The average price of the device is 20 USD. The other day, a friend brought me this PSU and says – he just bought it, on the same day, he carefully dropped it once and … that’s it. From above, the PSU is latched with a perforated cover, also made of a special profile. The body is durable, you can’t just bend or twist it in your hands, nothing staggers and doesn’t play in your hands.
The manufacturer is not bad.

USB and RJ45 inputs are located at the ends. There is no built-in battery, as on many other models of routers of this brand. The kit comes with only a thirty-centimeter cable, with the HAME brand logo, as well as a manual, which is not very useful in view of the fact that it is in Chinese. There are holes for the reset button next to the power input. Through the USB input, 3G modems are connected. * Intelligent design, easy to use Dimensions – 6.2*2.4*1.5 cm.
* 802.11b/g/n :150Mbps high speed WiFi * Name of item:Wireless router RJ45 can work both as a LAN and as a WAN (that is, through it you can both receive and-no, and give it away). The device is powered by USB. * Color:White The router arrived in its original branded blister pack, enclosed in a standard Chinese yellow package. The main characteristics of the product are listed on the back of the package, however, everything is in Chinese. * support 20 users in the website at the same time JPG” /> * Weight:0.071kg * Can connect ADSL, broadband automatically, recognize automatically and switch between WAN/LAN automatically To the right of it is an LED indication, which, depending on the situation, shines either red or blue. * Support HSPA/HSPA ,EVDO A/B, TD-SCDMA wireless network card * Micro USB plug:charging for A5 router * RJ45 plug:WAN(DHCP,ADSL,Static IP) or LAN There are stickers on the sides with the default settings of the router: admin panel IP address (, admin panel password (hame), MAC address, Wi-Fi network name, Wi-Fi password and serial number of the device. * Size:6.1×2.3×1.5cm The router can be quite miniature in size.

HAME A5 Mini 2-in-1 WiFi 150Mbps 802.11n/g/b WiFi Wireless 3G Router

Happy with both lights. 🙂 Muska in the summer. took a couple. satisfied. As long as the temperature stays positive.

no, I’m talking about the subject

Put it in the water supply well.

only I left before the new year on a business trip. true local, but every day. no time to write. Now I’m looking for antennas to them to increase the range of the waffle. preferably usb. do not offer a xlaomi repeater. guano. there is more than one.

No keyword

ps. complete blue acc 26650- for 3000 mAh … it could be worse. 🙂 I visit the site once a week, I read the data for the week.