I bought couple of Repairing Ubiquiti Lite AP 120 but they are all malfunctioning. One started to malfunction just after 3 to 4 months. Then I bought another and that 2nd radio antenna also got malfunctioning, also after using it after 5-6 months. Then again I bought another and it also seems malfunctioned because there is no signal from it and to know exactly I have to climb up the the communication tower.
I started to learn how to repair electronics circuit such as Ubiquiti radios, antenna and repair laptops. I think this is good step to take because I am running a WISP(Wireless Internet Service Provider) and I assume in the future lots of antenna and radio will be damaged and will needs repair. I have heard that lighting can damage Ubiquiti radio and antenna. But my Ubiquiti Lite AP 120 radio does not look like they were damaged by the lighting strikes. I think they got damaged due to the over-voltage. I am not sure about this right now.
I have two Lite AP radio at home. One looks like the power and reset are working but I cannot connect to it via the web interface. The other Lite AP radio has the blinking problem, that is, when the PoE adaptor is connected to it the LED on the PoE adaptor blinks. You can see that in the video below.
I looked around for Ubiquiti radio schematics but I could not find any on the internet. So to start I thought the only way to find the problem is to test individual components. Although I think even if I had the Ubiquiti schematic, I had to check the components so..
I started checking the capacitors of the Ubiquiti Lite AP 120 whose PoE adaptor LED blinks. I found one capacitor which had continuity on both of its sides. This is short circuit. I wrote on this in my note how to test SMD capacitor.
To ensure that that capacitor is the faulty component, I checked the capacitor on the 2nd Ubiquiti Lite AP 120 and that was not shorted. So I think I should be confident that the capacitor in the one which the PoE blinks is damaged. But to be completely sure, I have to desolder it and check it capacitance value.
But that is not all, I also have to check the inductors because more than one component could be faulty. I wrote note on how to check for faulty inductors in my earlier note Laptop Repair Finding Short circuit.
