[TenTec] SGC filter/Argo V?

[jcasey at notes.cc.sunysb.edu]

Hi John and gang,

I was happy to see your question.  Maybe we'll stimulate some discussion 
of the Argonaut V!

One might think that adding a DSP audio filter to the Argonaut V would be 
redundant, but I have found it helpful.  I have the external (high-level 
audio) version of the ADSP2.  The noise reduction function helps a great 
deal, even with noise that is not touched by the Argonaut V's noise 
blanker.  It is phenomenal on CW.  However, to my ear, the quality of SSB 
and AM signals is compromised significantly.  It MIGHT help pull weak SSB 
signals out of the noise, but I haven't used it in this way.

All of the bandpass filter widths are too narrow for my taste on SSB. They 
are great on CW though.  I believe the narrowest setting has considerably 
steeper skirts than that of the Argonaut V's DSP.  If a signal is outside 
the passband, you will never know it's there (unless, of course, it is 
affecting your AGC).

The high-level ADSP2 noticeably affects the audio passband, even when the 
noise reduction and bandpass filters are turned off.  Apparently, the 
ADSP2's audio amplifier has a narrower frequency response than that of the 
Argonaut V.  As a result, when listening to AM, I switch the ADSP2 
completely out of the audio chain.  I assume this would not be necessary 
with the low-level unit, since it does not provide audio amplification.

One minor note, I ordered mine on-line and SGC charged me $25 for standard 
shipping -- way too much for such a minuscule device.

73 & 72,
Jeff
WB5GWB at ARRL.NET
Long Island, NY