Observers not transmiting well the redstone signal

The redstone signal is interrupting when has to go one block down if the block it is standing is an observator

What I expected to happen was...:
the redstone signal going ininterrupted

What actually happened was...:
the redstone signal was not transmited to the block next to the observator

Steps to Reproduce:
1. put an observator one block above thee ground
2. place a line of redstone dust that goes above the observer
3. activate the redstone using a torch block or anithing that emmits redstone signal

4. this also works if the signal comes from the same observator