Carlos Quiroga

1.400

hace 6 años

Hello, to test them in circuit the most reliable is with digital multimeter.

ricbevi

17.055

hace 6 años

Things are not repaired by changing without a ton nor are they components for the mere fact that they are there because in the process you can make a mistake or complicate the future repair or make it unfeasible.
The resistors are measured with a multimeter but you must remove them from one side for a more reliable / accurate measurement.

Inter

4

hace 6 años

Indeed, that they are not changed by the mere fact of being there, they are changed because before they are checked - in this case the capacitors with a capacimeter -, and those that are wrong, they are preferably changed with their original value.
My question is about the form of resistance checking, with multimeter, of course. In this case it is appreciated his indication that the most reliable method is to detach from one end to measure its value. As I say, I am a beginner so I turn to experience because sometimes it is more reliable than texts and there are tips to keep in mind. Thanks and best regards.

ricbevi

17.055

hace 6 años

Detaching one end ensures that you measure that resistance only, there are times (SMD components) that it is not possible and you have to remove them from the plate to be able to measure them. When I doubt any, I measure it and above it, if the value is higher than what it marks on your body then I detach it and change it, if I do not follow since if it is cut it measures infinity (case more than that is marked) and I do not remember cases of common resistance in which the value decreased alone. Remember that the resistors have a tolerance of 5% in the newest ones and up to 20% in the oldest ones in + and -.

ricbevi

17.055

hace 6 años

The consistent way to repair according to my criteria is to know in blocks the stages that make up the device and discard one by one until circumscribing the fault to a sector and then within it.
Ex: audio stage, I start measuring supply voltage, speaker, then active elements and finally passive.
Generally to know if at least something is walking with touching the volume potentiometer at the end that goes towards it with the finger is enough to know if it amplifies why it will make a low frequency hum.