it makes me think about something too... i don't know about the interference of delay from the circuit but if you have a receiver of the resonant frequencies in that range, would it be helpful or harmful to amplify and repeat them?

the reason why i'm thinking of this is that the wavelengths are extremely long and a simple repeater would not create very much lag, under the microsecond range

the harm of exposure to radiation that suppresses reception of these frequencies has to do with them being squelched out and not received, and they are so slow (compared to electronic devices) that i think it is possible a schumann repeater would actually help a lot

in any case, we still receive this signal deep underground in caves... there is much evidence to suggest that during the disaster cycles of each 6000/12000 years humans lived in caves, the Magura Caves in Bulgaria are an example of this, and they even have depictions of what i think are Cosmic Thunderbolts (they look like a dancing girl stick figure) 

 oh yeah, and not to forget my other thought, a repeater like this would be dangerous in the event of a very strong pulse from a solar flare or filament eruption... this is also why i talk about having a tin shield on an underground structure as a refuge against the increasing amount of radiation that is getting to us because of the galactic current sheet... a repeater would be a device that might have some use above ground in normal conditions but it would definitely need to have a cut-out so when the voltage rises too high it stops repeating the signal 

 And why do you think this low frequencys are a problem ? 

 the voltage is the concern

voltage means electrons which means heat, which can mean damage to tissue that is tuned to absorb it (ie, endocrine system organs that receive ELF for clock sync)