[Lowfer] Using Argo

[ToddRoberts2001 at aol.com]

Hi Doug,
Have you tried using the R75 twin PBT to advantage? For it to work at 
its best you should have 2 x 250Hz filters, one in the 9 mHz IF and 
one in the 455 kHz IF. I find with careful adjustment of the twin PBT
I can narrow the IF down to about 80 - 100Hz or so. Also by playing
with the settings I can enhance the rejection of an unwanted carrier
on the "lower" side or "upper" side of the desired signal.
 
Like you mentioned this can be useful when using ARGO to help
keep an unwanted carrier from "bleeding over" into the desired 
QRSS display window.
 
73 - Todd WD4NGG
 
In a message dated 12/5/2012 5:20:59 P.M. Eastern Standard Time,  
kb4oer at gmail.com writes:
Well, I see no reason why your method of using SSB  USB mode would not work
with the R-75.

I have encountered a few  situations, however, where narrow filters helped
my QRSS reception. One  example for me is the 185.300 kHz USA Lowfer
"watering hole". I have a strong  PLC very close to this frequency, so close
that it is within the passband of  my R-75's narrowest CW filter (250 Hz). I
notice a distinct improvement in  QRSS reception resolution on this
frequency, using ARGO, when I use my  Winradio SDR and set the filter width
to 150 Hz or less. So yes, at least for  me, there are times when it is
advantageous to use a narrow filter (I.F.  audio, or software defined)
filter before sending the data on to Argo (or  Spectran or Spectrum Lab) for
QRSS decoding.

LF is different that 30  meters.

73, Doug KB4OER