How to fix a multimeter with the wires and pins coming loose
1, multimeter red and black pen in the stake, you can pull out, see a metal male socket connected to a leather wire, just because the junction of this line column is easy to break, tell you, my pen line has been much shorter, repair many times, each time to waste 1cm, I have two kinds of table (electronic, pointer) are unloading the line to repair the pointer table line connector is good to repair some, as long as there is a threaded red plastic on the set of unscrewing the metal stake clamped to a vise, use a soldering iron to melt on the solder wire, and then the leather wire stripped out half a centimetre to reveal the copper wire, melted with tin. In a vise, with a soldering iron melted on the solder wire, and then stripped out half a centimetre of the leather wire, exposing the copper wire, melted with tin, it is best to set an insulating wax tube on the line, so that after soldering outside the casing will not be easy to break.
2, for the digital table of the stake is not very good welding, it's plastic cover and big and hard, you have to pull out the first line through the line, welded in the outside and then return it to its original position, if you even welding technology are not, it would be difficult to get!
See the red pen stub above is the plastic sleeve that was repaired and then ironed firmly with a soldering iron to secure the crack.
People who can own and use a multimeter will have some knowledge and exposure to radio and electrical supplies for repairs, and will inevitably use a soldering iron, which can be taken apart and soldered.
Multimeter diode gear can light up the diode?
Multimeter has a diode gear, can be used to detect the diode, and can light up the diode. But the light is not absolute, there are two main reasons: 1) the multimeter diode gear voltage is low; 2) light-emitting diode operating voltage is high.
Multimeter diode gear voltage is generally about 3V, the voltage can light up ordinary light-emitting diodes, in measuring the diode is good or bad can be contacted with a red pen LED positive, black pen to the negative side of the LED, the LED is bright you can judge the LED is good. But some table output voltage is low can not light up the LED or only slightly light. I've used a cheaper multimeter from Unidux before, it can't light up the LED, the diode gear is basically useless, it's very inconvenient.
LED is a special kind of diode with forward conduction voltage drop, and this parameter varies greatly. Different colours of light-emitting diodes have different conduction voltage drops. Generally speaking, the red light-emitting diode conduction voltage drop is the smallest, about the range of (1.5-2) V; green is second, in (1.8-2.5) V or so; and the blue voltage drop is the highest, in (2-3.5) V or so. So, the same meter, when measuring different colours of LEDs, the brightness is not the same, usually red is the brightest and blue is the darkest. Even some colours cannot be lit.
