Hi Ken and LF

 

From my experience Winrad is not suitable for VLF reception. The fact that Dennis M0JXM can receive Chris (G3XIZ) on Winrad is that their aerials nearly touch (an exaggeration) but its about 1.5km separation. Dennis can read Chris real time. I have looked at the 9kc/s spectrum using Winrad but I could not get the band spread or the level of FFT iterations to resolve a signal as weak as Chris'. (I am sure some one tell me I am wrong). However all is not lost, Spec Lab is a free down load and runs on most Win OS. With Spec lab you can get down to mHz BW and have a 1 or 2Hz total display where the doubt and uncertainty are removed as to what signal you are getting. Not only that the frequency calibration can be automatically locked to one of the Mil stns further up the band.

I have spent ages trying to get a good signal from the low power VLF signals and I don't think it is easy, as Eddie and Stefan and Marcus will tell you because I have bothered them about it.

 

Where I live there are signals many many times stronger than Chris barely 1/2Hz away. When observe at the resolution required they appear very unstable whereas Chris' signal does not. It becomes obvious what you are looking at. By the stability standards required those very strong traces you are looking at are very unstable. They emanating from only a few yards away unless they can be identified as say a Mil stn or Line time base they are likely to be SMPSU or the like..

 

73 es GL Pete M0FMT IO91UX