SNR Margin increases...decreases..

[bajaj151]

During day time, SNR margin rate varies from 10-12 but during night it increases in range 18-22...

What may be the reason?

 

[bajaj151]

Any solution??

 

[whitestar_999]

most likely some cut/joint in line is exposed & during day time it is affected more by external factors like wind/insects/birds etc.