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Old November 19th 07, 10:42 PM posted to rec.radio.shortwave
[email protected] miso@sushi.com is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 317
Default Analog versus DSP

On Nov 19, 2:25 pm, wrote:
This thread seems to have migrated from a DSP vs. analog discussion to
one of ergonomics of buttons/knobs vs. menus.

What I'd really like to know is if there's any significant reason to
prefer a DSP-based receiver (e.g. the 756Pro-III) over an analog
receiver (e.g. AOR 7030+) on the basic of receiving performance.

Here's where I perceive DSP receivers to have the advantage:

* Sharper, narrower filters without artifacts (e.g. ringing)
* Easy updates via software download (TenTec supports this, does Icom?
(I doubt it))

and for analog:

* Higher dynamic range than most DSP receivers
* Lower cost (typically)
* Better audio

I had a chance to sit down and use a 756Pro-III for a few hours this
weekend, and I must say the spectrum scope is an addictive feature!


Digital filters ring unless they are sloppy. IIR filters ring. FIR
filters don't ring IF the tap coefficients are all positive, but then
the filter is sloppy. With DSP you have more control over the
bandwidth, but no freedom from ringing.

I don't think the 7030 is all that cheap once you buy the filter
daughter board and some crystal filters. The filters don't just
materialize in the radio. You need to solder them or pay someone to do
it.