Topband: Real Time DSP Software

[Herb Schoenbohm]

Dear Topbander,

Several weeks ago I mentioned the use of various noise reduction and CW 
signal processing software that  could turn the shack PC into a useful 
DSP processor for the reduction of noise, static, and  QRN. After 
playing  around with Cool Edit and  other noise reduction  downloads I 
realized the requirement for real time software.

Thanks to Pete, N4ZR some amateur designed software (Chromasound) for 
real time processing is available for a beta test at:

http://www.barberdsp.com   (It works for only 30 seconds but the 
evaluation is free. Registration, if you decide you like it, is $50)

Designed by Jim Barber, N7CXI Chromasound seems to have some promise, 
especially in high qrn areas and for those with older radios without 
sharp filters, adjustable NB, or Notch..  I also has CW filters 
adjustable down to 100 hz, an awesome carrier notch for SSB or AM, AGC 
and a display.  This unit works with Soundblaster 16 bit cards or above 
as well as many others.  Be sure to read the excellent documentation to 
get the unit to work properly.  The delay seems to be less than a second 
on a 200 Mhz Dell shack computer logger. It takes a little practice to 
tune slowly for the peak signal.  It can run in the background while you 
are running CT or other logging programs. Be sure to mute the "line in" 
on the task bar to prevent the coupling to the output.  If you don't 
have a line level output on your rig,  a "Y"  connection on you 
headphone jack  will work if you pad it down a bit or keep the levels 
reasonable.

Hope this information may help some topbanders in high QRN areas 
(lightning and thunderstorms) or those who need to update their RX 
capability. I would enjoy your comments sent to me.

73

Herb Schoenbohm, KV4FZ