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Re: Computer controlled radio seen at AMSAT Annual Meeting 03



The SDR-1000 seems to be designed for experimenters who are interested in
narrow-band weak-signal reception. A SDR for satellite users would be very
useful, but only if it digitizes at least a 1MHz band so that wideband data and
multiple simultaneous receive channels could be handled.

The was an SDR design published in QEX recently that digitized the entire HF
spectrum. The one flaw that I could see for satellite users was the use of a
single-channel digital downconverter. Multiple channels for simultaneous beacon
and voice or data reception would be useful.

73,

John
KD6OZH

----- Original Message -----
From: "Emily Clarke" <w0eec@AMSAT.Org>
To: <APBIDDLE@MAILAPS.ORG>
Cc: "amSAT" <amsat-bb@AMSAT.Org>
Sent: Monday, 15 December, 2003 01:52 UTC
Subject: RE: [amsat-bb] Computer controlled radio seen at AMSAT Annual Meeting
03


>
> I'm note quite as enthused as Alan after looking at the specs.  I own a
> PCR-1000 and in the short amount of time I have owned it it has taught me
> many things about radios and software, most of which has been less than an
> ideal "user experience."  Here are some of the problems I foresee with
> SDR's at this time:
>
> 1) Connections are old technology and require far too many connections
> (Parallel port, serial port, sound card) rather than a modern, progressive
> connection (USB 2.0 or firewire).
>
> 2) Required use of sound cards require drivers, not always available for
> the latest operating systems, and not always reliable.  (For example, my 3
> year old Sony notebook is no longer supported by WinXP because Sony doesn't
> have a driver for it.)
>
> 3) The software is unproven and written in Visual Basic (and not even the
> latest version.)  Although I don't own the SDR-1000 and it's software, if
> the software for the PCR-1000 is any indication there will be many
> problems.  The PCR-1000 came with the Icom software which crashed all the
> time and conflicted in namespace and file types with the more common Roxio
> CDRW software.  It also came with the Bonito software  which was already
> outdated as shipped and cost $$$ to upgrade to the latest version.  I also
> don't think it is up to commercial standards of quality.  In the end I paid
> even more money for a third party package (Talk PCR) that works OK though
> it does have some good features for use with AO-40.  Unfortunately this
> takes over interrupt priorities and the sound card, so it can't be used
> while you are running MixW, or any of the DSP software packages.
>
> 4) I disagree that it's relatively cheap.  If you buy the bundled
> transceiver and case you end up with an ICOM 703+ but lacking power (1W vs
> 10W for the 703+), an antenna tuner and a front panel.  You can build a
> computer interface for the 703+ for about $20 (or buy Icom's CT-17 for
> about $130).  I'd also consider the Icom 706 MKIIG or the Yaseu 897.
>
> 5) It appears to me you are stuck with using PC microphones.  Some would
> argue they sound terrible - I wouldn't disagree. While I'm sure there are
> some very nice commercially available headseats and microphones I'm not
> thrilled with the idea of using a keyboard space key as my push to talk
> switch.  I'll keep my Heil mic and the very nice speech processor built
> into my 910H  thank-you-very-much.
>
> 6) No Mac or Linux support.  A shame really...
>
> 7) To put together a full featured transceiver you have to deal with many
> vendors. So you add the DEMI 2M Transverter for $400, and then about $150
> for an HF power amp (Oh darn! Doesn't cover the 6m side), a VHF power amp
> and you still only have a 706 MKIIG or 897 minus the UHF coverage, at a
> price that is considerable higher.
>
> So as much as software defined radios seem to be cool at first glance, I am
> not convinced I would like to be rebooting my radio in the middle of a qso,
> or having to give up my radio because the software no longer runs on
> Windows 2005. Maybe in 10 years when the software gets mature and up to
> commercial quality, but until that time I don't think I'd go down that road
> except as a novel experiment.  It would help if the software was open
> source and could be re-developed in C++ on a common IDE, but that doesn't
> appear to be the case here.  In one to two years when Microsoft releases an
> OS that doesnt' support Visual Basic 6.0's runtime any longer it will be a
> rude awaking for anyone relying it.
>
> 73,
>
> Emily
>
>
> At 12:22 AM 12/15/2003 +0000, you wrote:
> >An impressive radio.  Not a factor for a TLM-only station, but I was a
> >little disappointed that it is inherently non-duplex.  On the other hand, it
> >is, as such things go, relatively cheap, so you could buy two of them, and a
> >second parallel port of course.  I discussed it a bit, and was told that
> >modifying the software would not be that big a deal.
> >
> >
> >Alan
> >WA4SCA
> >
> ---------------------------------
> W0EEC - CM87tm
> AMSAT Area Coordinator - San Francisco Bay Area
> http://www.projectoscar.net    http://www.emilyshouse.com/W0EEC
> http://www.experthams.net/ao7
>
> Help Launch Echo - http://www.amsat.org/amsat/sats/echo/index.html
> ---------------------------------
>
> ----
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>


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