Re: LF: TF3HZ

[Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de>]

Markus, Mike,

The effect disappears when local QRM comes up, like visible on his wideband window on the bottom of the page. So i assume it has to do with the noiseblanker and filter settings. Possibly the NB acts on DCF39 and HGA which may be in the passband of the SL internal filter. Halldor has a wideband RX since a few days and showed me the link: http://icas.to/lineup/idc-136-kit-eng.htm
Maybe i am increasing the average signal level when i am on air and so the NB is blanking rather seldom?

73, Stefan

Am 20.11.2011 19:06, schrieb Markus Vester:

Mike,

 

interesting. The propagation is probably by daytime D-layer reflection, which typically exhibits a flat maximum at noon time. This is conspicuouis eg. on the DCF / HGA plots from 4X and YO, and on Eu Loran-C signals as well. On the sea path between G and TF, this may be augmented by a groundwave component with relatively little attenuation.

 

BTW Stefan's strong DFCW signal is producing an unusual modulation effect on Halldór's grabber, as both the background noise and all other signals seem to brighten up during the dashes. Just like a kind of negative AGC...

 

Best 73,

Markus (DF6NM)

 

From: Mike Dennison

Sent: Sunday, November 20, 2011 5:41 PM

To: rsgb_lf_group@blacksheep.org

Subject: LF: TF3HZ

I was amazed to be received well on TF3HZ's grabber over a daylight
path from 1500 UTC today.

Mike, G3XDV
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