Ooops !! VLF
This is getting too fast, isn't it ? ;-)
Living in a 26th floor, my main enemy and at the same time my best friend is the elevator :-)))
The motor variators using three plase 380V are very noisy. Specially from DC to 10MHz
I have been trying to fix this even with the help of the lift maintenance company, but it is impossible. I have my antennas just on the roof cover of the
lift motors and controllers cabin. The variators include all the standar ferrite "filters" but can't fully solve the problem. It would probably need a matched
filter, not a standar "plug&play" but this things are under professional control and can't be touched without risks
That's why I keep my Rx at 9km in a different QTH. There is a MiniWhip there and a Perseus SDR
My plan for VLF is to connect the MiniWhip directly to the sundcard of the PC. A resistive splitter for the MiniWhip is what I have in mind for that
Perseus works down to 10KHz but not lower
Once you get "hands on work" with the coils, just imaging how big coil will I need for VLF gets me sweat :-)
But knowing the very good performance of the low bands here at 80m height that will really worth the effort
Ideas wellcome !
Hi Luis, VLF,
Luis, what about VLF in EA? Would you like to try to receive something from there? With a small active antenna on the top of the building you could do some first
RX tests to prepare for our first VLF QSO then :-)
What do you think?
LF is about 10x 'harder' then MF (for the ERP). But with the same ERP you can make much more distance on LF.
VLF (8270) is about 300x 'harder' then LF! So you can get a first impression... But you would need much less ERP to make the same distance on VLF! :-)
73, Stefan
