In this blog are some basic procedures for finding faults with PCBs and fixing those faults. Though there are many in circuit testing programs and probes available in the market for skilled technicians and test engineers professional essay writing service there are no general guidelines given for novice users.
Testing jobs are abundant in number. So for those of you who are new to PCB testing and troubleshooting here are some general guidelines which would surely help you solve most of your basic problems.
- If you face some problems like when you end up removing an entire track (connection from one component to another) on the PCB you can use a simple piece of wire to imitate the connection. Solder the two ends of the wire where you think the connection should be present on the PCB.
- Transistors can be damaged by heat when soldering or by misuse in a circuit. If you suspect that a transistor may be damaged there is an easy way to test it. Use a multi meter to check each pair of leads for conduction. Set a digital multi meter to diode test and an analog multi meter to a low resistance range. Test each pair of leads both ways:
- The base-emitter (BE) junction should behave like a diode and conduct one way only.
- The base-collector (BC) junction should behave like a diode and conduct one way only.
- The collector-emitter (CE) should not conduct either way.
- To test a capacitor, first short the capacitor leads for discharging it completely. Set the multi-meter to high resistance mode. Connect the multi-meter terminals to the capacitor leads. For electrolytic capacitors the positive terminal of multi-meter must be connected to the positive lead of the capacitor and negative terminal of multi-meter to the negative lead of capacitor. At the moment you connect the multi-meter terminals to the capacitor leads, the multi-meter needle will move to zero and then slowly move towards infinity and settle there. This will happen only if the capacitor under test is healthy.
- To check an ordinary silicon diode using a digital multi-meter, put the multi-meter selector switch in the diode check mode. Connect the positive lead of multi-meter to the anode and negative lead to cathode of the diode. If multi-meter displays a voltage between 0.6V to 0.7V, we can assume that the diode is healthy. This is the test for checking the forward conduction mode of diode.
- Though we have tried to cover most of the basic problems faced by new users, you might still face some problems which are circuit specific. Practical or hands-on experience will help you learn art of testing. Adormi product comes with its own testing and troubleshooting guide with different possible scenarios of possible errors to help you identify them better.