:white_check_mark: fix the damage done by a3f96c2c37
:white_check_mark: fix the damage done by a3f96c2c37

As suggested by @matthewware all zero frequency channels are fine to merge.

Should have run the unit-tests before pushing... Closes #76

Plourde-Research-Lab/PyQLab,calebjordan/PyQLab,rmcgurrin/PyQLab,BBN-Q/PyQLab