After finding the radio interference problem caused by a plug in power supply unit, (link to Thread), this also caused power quality issues to the Blitzortung lightning detector to which it was powering, here we have a before and after traces of background noise:

Pulses caused the automatic gain to be reduced, effecting the detection range.

Considerable improvement of signal quality.

Lightning detection trace, this trace was captured during the storm activity in the image below.

The green squares indicate stations online, the grey squares are stations that are currently offline.