I measured the 5000A's blocking with a 1 uV signal at 100 kHz spacing as 123 dB. Since there is no up-conversion filter, and the phase noise is strangely flat with frequency, at least out to 100 kHz, the spacing probably does not matter on the 5000A. I don't normally measure blocking at 2 kHz, or any frequency other than 100 kHz. At frequencies spacings outside the typical up conversion filter, say at 10 or 20 kHz for instance, blocking is often phase noise limited. Inside the up-conversion filter, blocking is normally significantly above the dynamic range value. Additionally, since we have to cope with transmitted phase noise so often today, if a signal is 2 kHz away, and is strong enough to approach the blocking value, the other guy's phase noise is likely a problem, (in addition to key clocks!). Of course the 2 kHz values are really only significant for CW (and I suppose RTTY). Transmitted splatter on SSB is much worse than most DR3 numbers at 2 kHz.
Second, a comment on why I now measure blocking at 1 uV. The League used to, and may still, measure blocking against an S5 signal. What level is S5? It varies greatly from radio to radio. Also, the AGC is obviously in the equation at S5, another variable that is hard to quantify. The League also may turn the AGC off, which is not likely how most of us use our radios. Also, what is "OFF" in a DSP radio? It likely does not exits, as the DSP has to be protected. A DSP chip does not overload gracefully. The K2 measured about 10 dB different with the AGC off vs the AGC on. So I don't want the AGC in the picture. If one uses S5 as the reference, some radios have the S meter going down as the blocking signals goes up. So the radio is blocking, but the audio output is not yet being affected. Finally, all these numbers are important, but the bottom line is: Do you like to operate your radio? Does it sound good? Two radios that lasted only 30 days in my shack are highly touted by many owners. They were the IC-7000 and the Watkins Johnson 8711A (commercial version of the HF-1000A). The attack distortion on SSB of the WJ made it unacceptable in my shack. It was fine on AM, but I don't work AM. The AGC of the IC-7000 drove me nuts, with all sorts of unacceptable artifacts on any kind of transient noise. Most features of the IC-7000 were superior to the 706MkIIG, but the 706 sounded good and the 7000 did not. I hated to give up the excellent noise blanker in the 7000, especially since it was my mobile rig, but the crazy sounds coming out of the 7000 trumped the excellent NB. 73, Rob Sherwood, NC0B >>> "Bill Tippett" <[EMAIL PROTECTED]> 9/18/2007 9:08 am >>> You're correct Tim...I had not looked in a long time. Of course ARRL does measure both BDR and IMDDR3 down to 1 kHz spacings (in their Expanded Test Report) and publishes 2 kHz measurements in the QST reviews. So we may eventually know, but I would hope Flex will publish a spec on BDR at some point. 73, Bill W4ZV On 9/18/07, Tim Ellison <[EMAIL PROTECTED]> wrote: > If you look at his web site, you will see that he does not list BDR, so > I suspect it will not be published. > > -Tim > ---- > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Bill Tippett > Sent: Tuesday, September 18, 2007 10:47 AM > To: FlexRadio@flex-radio.biz > Subject: [Flexradio] SDR-5000 - EHAM REVIEW - NEW SHERRIF IN TOWN > > > > "You will soon see the published numbers by Rob Sherwood on his website" > > He will also measure BDR at 2 kHz. What is the BDR spec > for the 5000 at 2 kHz spacing? > > 73, Bill W4ZV > > > _______________________________________________ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Knowledge Base: http://kb.flex-radio.com/ > FlexRadio Homepage: http://www.flex-radio.com/ > > _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/ _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
