18 - 40ch conversion
1 5
2 6
3 7
4 8
5 9
6 11
7 –
8 12
9 13
10 14
11 15
12 16
13 17
14 18
15 19
16 –
17 20
18 22
As you can see channel 7 & 16 are half channels. Now these channels are extremely quite and private if you have two 18ch radio's.