I am trying to repair some everyday electronics. I am not sure of how to measure the resistors. Firstly, when the resistor is soldered onto a circuit, the other resistors around it will affect the reading. Thus i am not sure to change the resistor or not. I need a good explanation on how to make measurements onto pcb parts such as resistors which are soldered.

 

Unless discolored, resistors are rarely a problem. If one is toasted, it's usually because some active device has failed. You get farther checking for PN junctions and capacitors.

"Everyday electronics" does cover some ground. A mention of the device and the symptoms could get better advice.

 

De solder the resistor? Or one end and measure with a meter

 

I am starting to repair Radios, and HiFi Systems. The problem is what to check inside? As you have said a faulty component should show a physical change. I also need a small help on how to fix Variable Capacitors. I accidentally turned one when cleaning. Thanks in advance.

 

I am not clear what your level of knowledge or skill is, or if this servicing is a casual operation or you intend to do lots. So it is difficult to advise on servicing technique.

Nor is it clear as to the age of the equipment proposed modern, old, vintage?

I do however have safety concerns and would strongly advise you to learn up on electrical safety, particulary if the equipment is vintage and/or mains driven.

 

Look up voltage drop. And welcome.
Dan

 

Troubleshoot starts with a good fundamental knowledge of electronics, the rest comes from experience. It's not the kind of troubleshooting where your eyes and your nose are the best instruments. You need to first train your mind. Take some training courses or classes and learn first how circuits are supposed to work and then you can start to understand why one specific circuit may not be working.

Lefty