It is first to confirm whether the voltage of each chip power supply pin is normal, and then check whether the various reference voltages are normal, and whether the working voltage of each point is normal or not. For example, when the general silicon triodes are conductive, the voltage of the BE junction is about 0. 7V ，and the CE junction voltage are about 0. 3V. If the BE junction voltage of a triode is greater than 0. 7V (except for a special triode, for example, a Darlington tube, etc.), it may be that the BE junction is open.
Add the signal source to the input, and then measure the waveform of each point in turn to see if it is normal to find the fault point. Sometimes we use simpler methods, such as holding a tweezer in our hand, to touch the input at all levels to see if the output is responding, which is often used in audio, video, and other amplifiers (but be careful. The circuit of the hot backboard or the circuit of high voltage, cannot use this method, otherwise may cause the electric shock). If there is no reaction at the front level, but there is a response at the post-collision level, the problem is at the previous level and it should be checked carefully.( pcb board fabrication)
Process of pcb manufacturing:
Our Company is UL,ISO9001,ROHS and GJB9001B certified.
Packing and Shipping:
1. How to Get a quotation?
For PCBs,pls send us the Gerber File.For PCBA,pls send us the Gerber file and BOM(Bill of Materials)
2. What is the MOQ?
No MOQ.1 pcs is ok.
3.What is the lead time?
For PCB orders,the lead time is 2 to 10 days.For PCBA orders,the lead time will be 15 to 30 days.
4.Will the boards be tested before shippment?
Yes,all PCBs will be tested by Flying Probe or E-test.For PCBA,we will have AOI,X-ray,and functional test
Email us to get a quote: firstname.lastname@example.org