The noise problems of SIEMENS cordless phones
According to my experience, the noise should be caused by your ADSL Internet cat, but it does not rule out the possibility of a strong interfering source nearby. If you turn off the Internet "cat" and then use the phone to make no noise, the output signal of the cat can not be filtered out by the demultiplexer. Please consider changing the separator or "cat"". Because there are no other bandpass filter products on the market.
There are several causes of noise in cordless phones:Self telephone problem. Including voice channel, line decoupling, feedback, integrated circuit operating point offset.Power problem. Master the use of alternating current rectifier power supply decoupling, electrolytic capacitor bulge, liquid flow failure. Charger charging, battery aging, voltage instability.Son, mother of code allowed, frequency deviation. Again, try to sub machine code.Near frequency interference nearby. You can try another place, if it's normal, it's frequency interference.
