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BLUE and BLUE resistors? What difference does it make what color they are, the main thing is that the resistance is more or less accurate! But the color will be the same as it is painted (Thais, Chinese, Nanai) ... ✔️ But not everything is as simple as it seems! https://zen.yandex.ru/media/dima/golu... Initially, I saw black and blue SMD resistors, but did not attach any importance to this. Studying the device of powerful (25-100 W) broadband amplifiers of foreign manufacture, I noticed that in some places blue (light blue) SMD resistors are used. Especially in places with high HF-microwave power (load, attenuator, feedback of output stages). Having replaced the resistor in one of the amplifiers with a regular black one of the same size, I got a disappointing result. After prolonged use (1-2 days), signs of destruction and almost complete failure appeared on the resistor. From the Internet, I seem to have found out that metal-film resistors are marked in blue. ✅ The color of the case determines the type of resistor, blue and light blue are metal-film, brown are carbon, light gray are safety/fusyble resistor... (fuses) ✔️ So why do we need these color subtleties Since resistors are practically coils, they have inductance and capacitance, which is why they behave poorly at high frequencies. To reduce these effects, various tricky winding schemes are used, for example, bifilar, winding on a flat carrier, and Ayrton-Perry winding. But for microwave circuits, these solutions are not enough and thin-film and foil resistors are used ✅ FOIL RESISTORS They use foil several microns thick, usually made of nickel-chromium with additives, located on a ceramic substrate. They are the most stable and accurate of all, despite the fact that they have been around since the 1960s. The required resistance is achieved by photoetching the foil. They have no inductance, have low capacitance, good stability and fast thermal stabilization. The tolerance can be within 0.001%. ✅ THIN-FILM RESISTORS - resistors are made by ion sputtering of nickel chromium CHROMIUM SICYLIDE on an insulating substrate. Then photoetching, abrasive or laser cleaning are used. Thick-film ones are made by screen printing. The film is a mixture of a binder, a carrier and a metal oxide. At the end of the process, abrasive or laser cleaning is used. ✔️ TKS FOR SUCH RESISTANTS is 1 ppm / C. With a temperature change of 80 C, a megaohm resistor will change its resistance by only 0.008% or 80 Ohms. The way such precision is achieved is interesting. As the temperature increases, so does the resistance. But the resistor is made in such a way that the increase in temperature causes the foil to shrink, causing the resistance to drop. The overall effect is that the resistance remains almost unchanged. They are mainly used for surface mounting. The film in thick-film resistors is 1000 times thicker than in thin-film resistors. These are the cheapest resistors, since thick film is cheaper. So here are HOW BLUE resistors are! #BlueResistors #BlueResistors For those who need details (I'm rarely there) https://zen.yandex.ru/dima https://vk.com/id26168899 https://ok.ru/profile/570092326202/ https://www.facebook.com/profile.php?...