Toshiba LCD and LED TV Repair
neyod
The tv was brought in from another technician who could not troubleshoot the tv fault properly and from my experience there is a resistor on power supply circuit that many technicians does not take note of when repairing this model of sharp tv.
Though the colour code on the resistor has wiped off but I tested it and detect its bad so I replace with a 39k resistor.The choke resistor is bad and was also replaced.
Thats all,I tested the tv now and it worked perfectly.
power supply of sharp tv repaired
neyod
A repair friend of mine asked me to help him out to replace this gamma ic with my microcomputer hot air gun .The tcon board is that of a 42inch samsung lcd tv with picture defect.
I have replace this ic and will keep you updated after fixing the board so keep visiting this blog.
I have replace this ic and will keep you updated after fixing the board so keep visiting this blog.
Desoldering and replacing gamma ic HX8915-A
neyod
The tv was brought in by a friend and the standby light blinks continuosly while the tv fails to start.
The tv uses an IP board as seen below
From my experience I knew this fault is always related to the power and mainboard so I decides to firstly check the power circuit.I detect drop in voltage across the power capacitor so also at the secondary side of sm transformer.I check the capacitance of the power cap using my digital meter and detect the capacitor reads 1.1 instead of 98 to 100uf.So definitely it might be the power cap is bad.
IMG_20150106_102247.jpg)
I replaced this power capacitor with another one of same value.I powered the tv and the blinking stopped.The standby light came on and the tv works perfectly
The tv uses an IP board as seen below
From my experience I knew this fault is always related to the power and mainboard so I decides to firstly check the power circuit.I detect drop in voltage across the power capacitor so also at the secondary side of sm transformer.I check the capacitance of the power cap using my digital meter and detect the capacitor reads 1.1 instead of 98 to 100uf.So definitely it might be the power cap is bad.
I replaced this power capacitor with another one of same value.I powered the tv and the blinking stopped.The standby light came on and the tv works perfectly
Lg Lcd Tv with standby light blinking continuosly
neyod
The digital multimeter are
of different types but the one I recommend and used myself for capacitance
reading is as shown below.
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.
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.
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.
How to test capacitance of a capacitor with a digital multimeter
neyod
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.
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.
Sharp Lcd Tv with no power repaired
neyod
Dead LG 21inch Ultraslim Tv Repaired
neyod
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
I ordered an IC from aliexpress.com
neyod
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.
sharp tv with flyback lines on screen repaired
neyod
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.
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.
I changed this resistor and the power supply works perfectly.
Dvd Power Supply Repaired
neyod
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