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Secrets of repairing household radio-electronic equipment

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If you want to clean the program switch contacts on the camcorder without disassembling it, the KONTAKT PRF7-78 fluid manufactured by TAEROSOL (Fin) amazingly helps. I inject through a thin tube (complete with a balloon) directly into the prog gap. gears. The penetrating power, washing and lubricating properties are simply amazing. Eternally wheezing volume controls in domestic equipment begin to work like new.

When repairing video equipment (tape recorder, player) there is a breakdown such as there is no image viewing back, viewing modes, rewinds, etc. are not always turned on. REASON - often it is simply necessary to wipe the contacts with alcohol on the command gear located on the LPM, lubricate again (I use panasonic grease).

When repairing a UPS both imported and Soviet TVs and video cards (especially if the power transistor knocks out, the fuse or safety resistor burns out), I recommend connecting a 40-100W light bulb later, depending on the power of the TV. If the problem has been corrected, the light should almost go out after a short period of time. If it continues to burn, you have the opportunity to test sections of the power supply circuit under pressure without risking breaking through another transistor.

Wherever applicable m / s ULF: the output is almost supply voltage, m / s is not heated - look for an electrolytic capacitor in a harness with a high leakage current!

How to quickly check if the handset or base transmitter is working.

Make a few turns around the antenna with a wire marked * on the tester, if the transmitter works, the arrow will deviate to the right, but there is one feature - you need to experimentally find the measurement limit and the type of current.

Power supply protection.

The most common malfunction in imported TVs is the failure of the power supply. After searching for faulty elements and replacing them, it is necessary to check the performance of the power supply. In order to prevent the expensive components of the power supply from burning out again, it is necessary to turn on a 220 volt 150-200 watt incandescent lamp in series. In the event of a short circuit, the lamp will glow brightly, the resistance of the filament will increase, and the current passing through the powerful transistor of the power supply will not exceed the value necessary for its breakdown. It is necessary to continue searching for faulty elements. If the lamp is illuminated a little or burns half-heartedly, then the power supply is working.

Feature phones do not ring on paired numbers.

It is treated as follows - the resistance of the resistor in the circuit separating capacitance - quenching resistor - chime of the call decreases. In the original, there is a resistor from 6 kOhm to 22 kOhm. And in each case, an individual selection is required. The spread is quite wide from 4 ohms to 330 ohms. The upper limit is determined by the sensitivity of the call according to the call itself, and the lower limit is determined by the response to dialing by your own dialer.

The device hooks up the line, there is no set.

Measure the resistance of the line wires towards the device with an ohmmeter, it is hundreds of ohms, immediately find the reed relay, check the contacts in it, they are probably stuck. If so, feel free to change it to RES-55.

Sound adaptation in imported TVs

Option 1. You need to find a point in the circuit where the low-frequency sound signal goes, tear it off from the signal source, and send an audio signal there from the UPCHZ-2, which should be installed somewhere with a "canopy". UPCHZ-2 is powered by 9-12v, which is also not a problem to find, a video signal is fed to it through a capacitance of 50-100 peaks.

Option 2. Find IF sound filters (5.5 MHz, 2 pieces) and replace them with domestic 6.5 MHz ones.

A few words about remotes

As practice has shown, either the matrix of buttons fails in the consoles, or the LED "sits down". At the last fault, the LED changes and, if necessary, a limiting resistor is selected. It is better to replace the button matrix, although some craftsmen put foil under the buttons, etc.

How to launch MP-3-3, MP-1 on duty.

It is necessary to solder a capacitor between the collector and the base of the transistor, which is in the stabilization circuit (start with 470 pF, up to 4-10 nF, until you achieve a stable duty room). It also helps to increase the capacitance of the power supply rectifier filter for this very stabilizer.

Memory 12V+

In modern car radios, several power wires are used: to power the power amplifier, to turn on the backlight when the car's dimensions are turned on, to power the memory, etc. the wire that feeds the power amplifier usually has a thick section and a powerful fuse is installed on it - this is the main power supply for the car radio. Usually this is medium and high-end equipment with a digital tuning scale and memory, where information about tuning the radio receiver at the station is entered, which allows you to search for stations by dialing only the station number (button). Another option where an additional wire is used is receivers with the ability to code and in order not to enter an access code every time it is turned on, a memory chip is used that is powered by a battery with a separate wire (it can be yellow or red, but of small section). From this it follows: in order for the car radio to work correctly, it is necessary to connect a thin power wire directly (without any switching), this is the "Memory 12V +" wire to the battery, and a thick wire can be connected through switching elements like an ignition switch or an additional switch.

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An international team of researchers from Japan and Finland will work to create technologies and standards for the sixth generation of wireless communications, commonly known as 6G, as part of a joint research agreement between the two countries.

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