How to test capacitance of a capacitor with a digital multimeter


The digital multimeter are of different types but the one I recommend and used myself for capacitance reading is as shown below.
 There are esr meters which are those dedicated for capacitor readings but are somehow expensive infact it is somehow difficult to found here in Nigeria that is the reason why I stick to the digital meter for capacitance reading and it has really helped me a lot.

How I make the readings
      Notice the position of the probe.the positive probe removed and positioned as seen and on the meter you range it to the capacitive range(marked F) as shown

 








The only disadvantage of this meter is that it only reads up to 200uf any value higher than this is unreadable it only gives value of 1.but I specially have a method i use to measure value higher than 200uf but i will write-about that later.
in this test below i am reading a polyester capacitor of value 105j 400v.what i am testing is the capacitance which is 105j.this value is 105=1000000pf 001
alternatively,
1000000pf=1uf.
since the value of my cap is 1uf.to check if this cap is good i range my meter to 2uf or 20uf. i range mine to 20uf and from the picture you can see that my reading is 0.95 which is approximately 1uf.

 this means this cap is in good condition.you can also same method for other type of capacitors.Hope this little tutorial helps.if you have any question you can ask using the comment box.
tutorials

neyod
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Sharp Lcd Tv with no power repaired
The tv was hit by a high voltage and fails to power on.This is the internal structure of the tv









since it is a dead set the first thing is to check the power board.The board is intact without any burnt component on it.The reason why I am expecting to see a burnt component is because it was hit by a high voltage but was amazed when I could not found none.I tested all components at power and all tested fine except for the power ic which cannot be tested with the multimeter.
I set my meter to the volt range and test.It was then I detect a flunctuating voltage at one of the terminals of this ic









Thinking maybe this ic is bad,I decide to make test at the secondary side of the sm transformer.It was there I detect the same fluctuating voltage at the rectifier diodes terminal at this side.I tested the diodes and detect that one of it is faulty











I replace this diode with the same specification.After the replacement I power the tv and it works perfectly.

lcd television repair

neyod
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Dead LG 21inch Ultraslim Tv Repaired
The tv uses str w6556 as the switching ic.This ic is shorted,so I replaced it.Switching on the tv I discover that as the tv is about to raster the ic trip off .The ic was shorted again.Line transformers use to be a major problem of this tv so I concluded it is bad and went to buy another flyback tranformer.I fixed the transformer but what I saw when testing the tv is a small wavy picture on screen and the tv went off a few seconds and stayed in standby mode.As I was testing the components on the power supply I tested the power capacitor and to my suprise the capacitor is seriously bad though it looks okay judging from the look of the eye. I changed the capacitor and tv starts working again.

crt television fault repair

neyod
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I ordered an IC from aliexpress.com





I want to repair a 42" plasma tv but needed a smd ic (fds4435).I tried searching around but could not find it so i placed an order on aliexpress and it was delivered today.It took 17 days for it to reach me here in Nigeria though i had already urged the owner of the tv to be a little bit patient and he agreed.Now its time to finish the repair.I will update you immediately i finish repairing the plasma tv.

posted from Bloggeroid

electronics component tips

neyod
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sharp tv with flyback lines on screen repaired










The display of the tv is as shown above.
Observation
Voltages on blue and red cathode on tube base is 180v except for the green cathode which is low at 27v









Thought initially that the 15k resistor that supplies the green cathode is bad but on testing it I detect it was good







After some minutes of serious troubleshooting I detect that the drive transistor of value F421 is bad.I changed it and the fault clear away.







conclusion
I wanted to change the whole of the tube base before I decide to troubleshoot the fault,this help build the skill of a repair technician.This is the tv working perfectly.




















crt television fault repair

neyod
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Dvd Power Supply Repaired
The latest trend among repair technicians is just to change the power supply completely with another one.This saves time but what I observe is that it tends to make one lazy when it comes to troubleshooting faults.I decide to troubleshoot this power supply and repair it.
     It uses D13005 transistor and after checking components on board I could not detect any faulty component.I plugged the dvd and switch it on but it remain dead.Looking closely I start testing resistors at primary side and it was then I detect a bad resistor of 1meg ohms.
This was easily detected on board through the help of my digital multimeter,it will not have been easy with the analogue meter majorly because of the low ohms range.It is advisable to master the use of the digital meter also.I make use of both multimeters very well.
I changed this resistor and the power supply works perfectly.

dvd player repair

neyod
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The best way I test relay switch
I want to explain how I test relay switches.As we know relays are of different types but I will be emphasizing on the one mostly used in voltage stabilizers and this is because some of my repair friends are interested in knowing how to repair voltage stabilizers and one of the first step to repairing it is to know how to test relays.
 Relay switch and its symbol is as shown below,
























It has five terminals as shown above.You can test using the battery or through multimeters.
                                                Testing using the 9v battery
This is simple,using terminals 1 and 3 connect the battery to the relay.A clicking sound will be heard, the battery can be connected either way.This should be done within a second so as not to damage the coil on the relay switch.
                                                     Testing with multimeter
Set your meter at the ohms range and test terminals 1 and 3,there will be deflection of around 200 ohms will terminals 2 and 5 gives 0 ohms reading.
       Do you know of any other method of testing relay switch?please do share with us using  the comment box.
electronics component tips

neyod
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Tv with standby light only repaired
The tv is a 21" durabrand crt television and when switched on it will be on standby only.After carefully examining the tv i find it difficult to detect the fault.This fault is always related to eeprom but I could not find a replacement for this ic so I conclude I am going to change the board.
After two weeks of abandoning this tv I decide to recheck it again,it was then i detect a faulty capacitor at the secondary side of sm transformer
.The value of the capacitor is 470uf 16v but gives 13uf on my esr meter.I changed it with capacitor of same value.








This is the tv back in good working condition.
crt television fault repair , standbylight lit only

neyod
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Toshiba tv hit by thunder repaired
This problem usually occur in our country and this is because lots of building has poor earth system to guide against damages that may occur due to thunderstrike.


In this tv the standby light will be lit but the tv fail to come up.I tested and confirmed most of components to be good.supply to horizontal section is alright so definitely there is problem with the oscillator section because it is always the worst hit when thunderstrike occurs.The oscillating ic is stv2246c and need to be replaced.I source for another one and replace it.The tv works perfectly and the owner was happy to see his tv in action again.

crt television fault repair

neyod
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