[namo]

I have wifi adapter that catch the signal from a omni wifi AP. Durning the day, I don't get any signal and in the evening, I get 20% signal strength.

What is the reason for the morning drop?

[JohnWill]

Sounds like wireless interference of some kind. Have you tried changing channels?

[namo]

I have channel 11 set. I get better result when I set it to auto. However, in this case, channel 12 or 13 are choosen which not all devices suppport.

[JohnWill]

Try channel 1 or 6, my luck with Auto sucks as a rule.

[namo]

what I have is acually AP and 2 repeater, and here is the channel of other APs for other people that these three can see:

AP
6 (B+G)
1 (B+G)
6 (B+G)
1 (B+G)
11 (B+G)
7 (B+G)
1 (B+G)
1 (B+G)
1 (B+G)
11 (B+G)

Repeater 1
6 (B+G)
11 (B+G)
7 (B+G)
1 (B+G)
6 (B+G)
1 (B+G)
1 (B+G)

Repeater 2
11 (B+G)
7 (B+G)
11 (B+G)
11 (B+G)
1 (B+G)
1 (B+G)

Note: AP can see both repeater but I don't include this because they will be the channel I choose.

[TerryNet]

If those signals are all the same strength then I'd guess that 3, 4 and 9 would be your best choices to try.