LG microwave oven that does not heat up. LG MS-204H

This microwave oven was brought to my shop for repair and the problem was, it does not heat up. While the customer awaits in my shop, I did a small test. I put some water inside the microwave oven and tried to see if it heats the water or not. When turning on the oven, I could hear a loud noise coming from inside the microwave oven and it did not heat up the water.
From experience, when the microwave oven does not heat up, there is three possibilities:
1- The 220 volts is not reaching the main power transformer
2- The magnetron is shorted out
3- The .70 amp/5000 volts fuse between the 220 volts power transformer and the main capacitor is open causing the magnetron not to work due to the absence of power there.
By testing, I could read 220 volts reaching the main power transformer. The magnetron is not shorted out; This testing is done by testing the ohm reading between the metal body of the magnetron and the two terminals of the magnetron. If you get any reading between the terminals and the magnetron metal body, it is shorted and needed to be replaced. Usually the two terminals are connected together from the inside. It you test these two terminals with a continuity test setting, you will hear a beep. That is very normal.
I checked the fuse that is connecting the transformer to the main capacitor and it was open. this is a common problem in microwaves oven to find an open fuse there. Many repair technicians replace the fuse with higher amp rating causing the magnetron to blown or shorted it on the long run. It is very important to replace it with the same fuse specification to avoid any kind of problem in the microwave oven.
I replaced the fuse and turned the machine on. It worked and the water I put in the microwave oven started to get hot. One more problem remained; that is the loud noise of the oven. It was not suppose to have this loud noise. Usually, this is a problem with the main capacitor in the microwave and I think that is the main reason why the fuse was blown in the first place.
It is a very easy process to replace the capacitors but it is very important to make sure that the old capacitor in the microwave oven is discharged before replacing it. Even if the capacitor is bad, just make sure, it was discharged before replacing it with a new one. Upon replacing the old capacitor with a new one, the noise was gone.
The microwave ovens are very easy to fix and it can generated good income if you know how to do it. Just be careful when dealing with capacitors and magnetrons. Enjoy your repair and be safe.

Hivion digital broadcasting satellite receiver. Model HV9191X

An old man brought this satellite receiver to be fixed. It was a dead receiver. Took the cover off and scanned the power board with my naked eye but could not see anything there.

I powered up the receiver and started to test the voltages in the secondary power supply. All the diodes in the secondary section were not getting any kind of voltages whatsoever. That is an indication of a bad primary power supply. I tested the voltages at the main capacitor and I could read the 300 volts there.

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Dead LCD computer screen repair. Model HSTND-2A01

A photographer in a nearby store brought this LCD computer screen to my shop. The problem was a blinking stand by light when hitting the power button. After hitting the power button for 4-5 times, the screen comes on but for a while then it shuts down.
The moment I heard that from the client, I know it was a capacitor problem. The guy told me that he sent it to another repair guy but he could not figure out the problem. So I told him, I will do my best in solving this problem in this LCD monitor.
I took the cover off, and started checking for bad capacitors in the primary and the secondary sections of the power supply and all checked out ok. I moved to the high tension area of the board and I found two capacitors. They were 1000uf/25 volts. I checked them with my ESR meter and both of them gave me a high reading indicating a problem there.
I replaced both of them and rested the LCD computer monitor and it worked fine. I connected the monitor to my laptop and let it run for more than two hours and it did not shut down.
I called the customer who was really shocked that is actually worked. I asked him a question to where he sent the LCD computer monitor to be fixed. It turned out that this guy is a computer guy and has no experience in electronics repair. I gave the LCD monitor to the owner and he paid well for the repair and told me how happy he was to deal with such a guy like me. He said that he has a lot of computer monitors and a lot of electronic equipment that need to be fixed. I was so happy that he liked my worked and that more repair work coming to my shop soon.
This also gave me an idea about the computer guy who could not fix the LCD monitor. I called this guy and then I went to meet him in his shop. We talked about working together; He installs computers and I can fix things needed for his customers. I was so happy to make this deal and that my business is moving forward.