Analog versus DSP
On Nov 21, 6:55 am, wrote:
wrote
Regarding ringing, the sharper the filter, the more it rings. You
can't fight physics. I really annoys me how people think digital is
the solution to everything without really understanding the nuances.
You have obviously never worked a top line radio like the Icom IC-756
PRO III on CW with a narrow DSP filter. I assure you that even as
narrow as 50 hertz
THERE IS NO RINGING
If you don't believe me I am quite prepared to e-mail anyone an MP3
recording of the 50 Hertz filter working a beacon.
I also have many DX mates who work CW beacons and use Timewave DSP
filters right down to 8 hertz and I have never heard them complain of
ringing.
John Plimmer, Montagu, Western Cape Province, South Africa
South 33 d 47 m 32 s, East 20 d 07 m 32 s
RX Icom IC-756 PRO III with MW mods
Drake SW8 & ERGO software
Sony 7600D, GE SRIII, Redsun RP2100
BW XCR 30, Sangean 803A.
Antenna's RF Systems DX 1 Pro Mk II, Datong AD-270
Kiwa MW Loop, PAORDT Roelof mini-whiphttp://www.dxing.info/about/dxers/plimmer.dx
I have a JSP digital. Narrow the BW down, it rings. Believe whatever
you want, but you can't fight physics.
Now there is a trick you can do on beacons to get less ringing, but it
is a noncausal solution. If you are just IDing beacons, you don't need
real time DSP. Recprd the audio on your PC. You reverse the audio,
filter it, reverse it again, then filter again. This puts some of the
filter artifacts before the beacon pings, rather than all the
artifacts occuring after the ping. No DSP in a radio can do this.
See, I like DSP, but I use it where it does some good. I don't hammer
with a screw driver.
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