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Useful tips. HAM Tips
You can get an inconspicuous and very strong connection at the molecular level by moistening the cracked plastic with acetone or a nitro solvent. PVC tubes are easier to pull on insulated objects (screwdrivers, tweezers, radio components) if they are placed in acetone for 15-20 minutes. A large part can also be soldered with an ordinary soldering iron (25-40 W), if you heat it up, for example, on a gas stove. Sections of the upper insulation of the TV cable can serve as handles for turning the potentiometers. A chocolate wrapper with foil on one side is a good material for impromptu shielding of RF structures. By applying a high (~ 8 kV) voltage from the TV to the central core of an individual antenna (not to be confused with a collective one!), you can remotely restore contact in the copper (tin) - iron galvanic coupler. Roughly silvered plates from old PTK TVs can serve as material for the manufacture and repair of contact devices (for example, a refrigerator relay-regulator). Contact brushes for micro parts, electric shavers, etc. can be cut out of graphite rods from old batteries. Zinc for soldering acid can be found in old batteries. Connecting a ceramic or metal-paper smaller capacity (1/10-1/100 electrolytic capacitance) in parallel to a Soviet-made pass-through electrolytic capacitor significantly improves the sound quality in the UMZCH. The simplest indicator for checking a horizontal-scan transformer is a neon light bulb or an electrician's indicator. When you bring it to the horizontal transformer due to the scattered electromagnetic field, it glows. By the distance from the TVS the glow occurs, one can judge the health of the entire horizontal scanning unit. For tube TVs, this is 10-12 cm, for ZUSCT TVs, 10-15 cm. When repairing the TV, do not place a table lamp on its body. She will definitely fall and beat off the neck of the kinescope. When soldering parts over the neck of the kinescope, cover it with a piece of cloth, this will protect the kinescope from accidentally falling molten solder and, consequently, from cracks in its glass. When repairing a switching power supply (UPS), disconnect it from the TV and load it with a 75 W light bulb at 220 V. This way you will protect the microcircuits and transistors of the TV from damage due to possible power surges that occur when repairing the UPS, especially the stabilizer. After turning on the TV, switch from the remote control (RC) no earlier than 4-5 s, since during transients in the power supply (until the nominal supply voltages are reached), the behavior of the microcontroller (processor) and its PROM is not predictable. For the same reason, it is not recommended to turn the TV on and off repeatedly with the button. Do not let children play with the remote control when the TV is on, because by randomly pressing the buttons, you can put the TV into service mode and deprogram its microcontroller with PROM. The abundance of dust inside the TV is caused by the presence of high voltage and an electrostatic field in it. Dust particles on the boards and parts of the TV line up in chains along the electric field lines and are dangerous because they significantly reduce the insulation resistance. This leads to increased current leakage, spark discharges and, as a result, to insulation breakdowns and damage to the TV. Therefore, dust must be removed at least once a year. Dust removal is best done by sweeping it off with a soft brush and suction with a vacuum cleaner. Cleaning dust inside the case should not be neglected, since its abundance can cause spontaneous combustion of TVs, especially lamp ones. Turn on the soldering iron in standby heating through the diode, this will significantly extend its life. When replacing electrolytic capacitors, in addition to observing the polarity, the permissible operating voltage should not be significantly exceeded. For example, if a capacitor is designed for an operating voltage of 16 V, then when installing a new one of the same capacity, but rated for a voltage of 300 V, after a short operation, it will be disassembled, and its capacity will decrease significantly. The presence of high voltage on the suction cup can be checked with a screwdriver connected to the housing through a 3-5 MΩ resistor. The presence of a resistor is mandatory, since without it, due to the high current, a multiplier or line transformer of the TDKS type can be damaged. Store the ICs in a package that shorts their leads, such as wrapped in aluminum foil. When carrying, do not touch the pins of the microcircuit, take it by the case, otherwise your static electricity may damage the microcircuit. Solder only when the TV is turned off, otherwise shorting the tracks (even for a short time) will introduce new faults. Sometimes in a TV set, printed circuit boards get charred (burn out) from elevated temperatures. When repairing, be sure to cut this place and cover it with some kind of glue. Otherwise, there will be current leakage and sparking in the charred place due to low insulation. In cable TV, some channels come at a high level and interfere with others when the TV sensitivity is high. This influence is manifested in the overlay of two images: frames of the interfering image float in the horizontal direction along the main one. To get rid of this, turn down the sensitivity of the TV with the AGC trimmer. In cable television, the first frequency channel is heavily interfered with by radiotelephones operating on the same frequencies. The influence appears during a telephone conversation in the form of a grid on the screen. It is not possible to get rid of this “neighborhood” by careful shielding of cables and junction boxes. It's not the TV's fault. There is only one way out: to ask the owners of the cable TV network to switch your favorite program to another channel. If one of the resonant regulator chokes roars, drive a wooden wedge between its coils. The probe will become universal if you solder a "crocodile" in a rubber case on the reverse side of it on a short wire. You can make rosin yourself by collecting pine (not spruce!) resin in the forest and melting it in a tin can. Steel contacts treated with an aqueous solution of alkali (for example, the battery compartment of a portable radio or remote control) will never rust. From the old knitting needles from a bicycle or an umbrella, fused with a soldering iron into cylindrical pieces of plastic, convenient adjusting screwdrivers are obtained. Sprinkling the soldering place with sand or rubbing it with a crumbling stone, even aluminum can be soldered using conventional methods. Instead of a high-voltage wire, you can use a regular one by passing it through a tube from a dropper. Dielectric (diamagnetic) screwdrivers can be cut out of old fiberglass boards. A magnet wrapped in paper or polyethylene will help sort all sorts of things. When replacing a radio component, you can free the hole from the solder with a pointed match. The output voltage of the diode bridge, consisting of four diodes, can be increased by 1,5-2 times. To do this, it is necessary to connect a capacitor with a capacity of at least C, which is used in the rectifier, in parallel with any of the four diodes. This is convenient when, when replacing a burned-out transformer, the secondary winding does not produce the required voltage, and it is impossible to rewind it, since the replaced one is filled with sealant. You can use the braid of a television cable for TV subscriber connection in multi-storey buildings for grounding. This is especially convenient when you need to solder field-effect transistors and microcircuits, but there is no ground nearby. Using the antenna jack and a piece of wire, you can easily get out of a difficult situation. Authors: V.A. Nikitin, A.M. Dryuchilo, Y. Bearded, N.P. Vlasyuk, S. Rybchenko
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