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Re: [softrock40] phase noise

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  • KD5NWA
    A receiver with a good Norton pre-amp that can be bypassed, followed by a DBDM mixer then a IF QSD detector, with of course a clean LO for the mixers would
    Message 1 of 21 , Jun 1, 2006
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      A receiver with a good Norton pre-amp that can be bypassed, followed by a DBDM mixer then a IF QSD detector, with of course a clean LO for the mixers would make an excellent radio that is tough, agile, and multi-mode capable. All the while being a very simple radio.


      At 01:59 PM 6/1/2006, you wrote:
      I AGREE!!!!!!!!!

      Ford Peterson <ford@...> wrote:
      Bill wrote:

      > Francis,
      >
      > Thank you for posting that. Personally, I believe that is the biggest
      > single problem with these SDR type radios.
      >
      > Bill WB5TCO

      "that is" being phase noise of course.

      Actually, your comment is true, but not because of the "SDR type radios." These extremely simple receiver mixers are simply responding to the simply aweful Local Oscillators (by modern standards)that many of us are using to run the SR series mixers. Garbage-in / garbage-out as they say.

      My personal view is that there is likely no substitute for the multi-conversion receiver. We have become accustomed to enjoying the ability to QSY from the AM broadcast band up to 440MHz (and higher) with the touch of a button on most modern radios. I can see using an SDR type of mixer to acquire base-band data, and replace a large segment of a traditional radio using the sound card. But performance will be lack-luster at best when you QSY to any upper band without first performing a block-conversion of that band using traditional mixers and LOs. There is likely no substitute for traditional block conversion down to a reasonable frequency for the SDR to deal with. If you want real performance, then the focus of attention should be on the LO. Clean, frequency agile, spurious free, low-phase noise LOs is the name of the game. Use these nifty detectors as the final conversion from a relatively low frequency IF to your ears--and make that LO pristine clean of course.

      Ford-N0FP
      ford@...




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      Cecil Bayona
      KD5NWA
      www.qrpradio.com

      "Windows, the most successful software virus ever" Don Seglio Batuna

    • riese-k3djc@juno.com
      right wing conspiracy K3DJC ...
      Message 2 of 21 , Jun 1, 2006
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        right wing conspiracy

        K3DJC
        On Thu, 01 Jun 2006 13:17:23 -0500 KD5NWA <KD5NWA@...> writes:
        > According to some, phase noise and jitter is a vast conspiracy.
        >
        > At 11:49 AM 6/1/2006, Bill Dumke wrote:
        > >Francis,
        > >
        > >Thank you for posting that. Personally, I believe that is the
        > biggest
        > >single problem with these SDR type radios.
        > >
        > >Bill WB5TCO
        > >
        > >FRANCIS CARCIA wrote:
        > >
        > > > I just found a good article on measuring phase noise. I have
        > used the
        > > > one with a mixer and HP8640B. It is uploaded into the file area.
        > gfz
        > > >
        > > >
        > > > SPONSORED LINKS
        > > > Ham radio
        > > >
        > >
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        <http://groups.yahoo.com/gads?t=ms&k=Ham+radio&w1=Ham+radio&c=1&s=15&.sig
        =t8IpznzYq-E2LbCrDXaGPQ>
        >
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        > Cecil Bayona
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      • KD5NWA
        Sorry, I m pretty far to the right and I believe in phase noise, I believe in jitter. This one must be a far left wing conspiracy. ... Cecil Bayona KD5NWA
        Message 3 of 21 , Jun 1, 2006
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          Sorry, I'm pretty far to the right and I believe in phase noise, I
          believe in jitter. This one must be a far left wing conspiracy.

          At 02:28 PM 6/1/2006, you wrote:
          >right wing conspiracy
          >
          >K3DJC
          >On Thu, 01 Jun 2006 13:17:23 -0500 KD5NWA <KD5NWA@...> writes:
          > > According to some, phase noise and jitter is a vast conspiracy.
          > >
          > > At 11:49 AM 6/1/2006, Bill Dumke wrote:
          > > >Francis,
          > > >
          > > >Thank you for posting that. Personally, I believe that is the
          > > biggest
          > > >single problem with these SDR type radios.
          > > >
          > > >Bill WB5TCO
          > > >
          > > >FRANCIS CARCIA wrote:
          > > >
          > > > > I just found a good article on measuring phase noise. I have
          > > used the
          > > > > one with a mixer and HP8640B. It is uploaded into the file area.
          > > gfz
          > > > >
          > > > >
          > > > > SPONSORED LINKS
          > > > > Ham radio
          > > > >
          > > >
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          ><http://groups.yahoo.com/gads?t=ms&k=Ham+radio&w1=Ham+radio&c=1&s=15&.sig
          >=t8IpznzYq-E2LbCrDXaGPQ>
          > >
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          > > >Yahoo! Groups Links
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          > > Cecil Bayona
          > > KD5NWA
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          > >
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          Cecil Bayona
          KD5NWA
          www.qrpradio.com

          "Windows, the most successful software virus ever" Don Seglio Batuna
        • Phil Covington
          ... Duplicate the K2 front end and it s PLL without the DAC tuned reference oscillator (we can deal with the 5kHz steps in software) - run the 5 MHz IF into a
          Message 4 of 21 , Jun 1, 2006
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            --- In softrock40@yahoogroups.com, KD5NWA <KD5NWA@...> wrote:
            >
            > A receiver with a good Norton pre-amp that can be bypassed, followed
            > by a DBDM mixer then a IF QSD detector, with of course a clean LO for
            > the mixers would make an excellent radio that is tough, agile, and
            > multi-mode capable. All the while being a very simple radio.
            >

            Duplicate the K2 front end and it's PLL without the DAC tuned
            reference oscillator (we can deal with the 5kHz steps in software) -
            run the 5 MHz IF into a QSD (20 MHz low phase noise xtal osc divided
            by 4 to get quadrature) - I think this would be an excellent marriage
            of K2 and SDR. No DDS. I have wanted to try this since 2003, but
            keep getting sidetracked.

            73 de Phil N8VB
          • Rob Campbell
            I managed to get a couple of hours after work today so here are the results of my testing so far: Signal (dBm) Winrad display (dB) Comment ... -32
            Message 5 of 21 , Jun 1, 2006
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              I managed to get a couple of hours after work today so here are the
              results of my testing so far:

              Signal (dBm) Winrad display (dB) Comment
              ------------ ------------------- -------
              -32 0 multiple harmonics visible
              -32.2 -2 S8
              -40 -5 S7
              -50 -15 S6
              -60 -25 S5
              -70 -35 S4
              -80 -45 S3
              -90 -55 S2
              -100 -65 S1/S2
              -110 -75 S1
              -120 -85 <S1
              -130 -95 see note 1 below
              -134 -** see note 2
              -135 -** see note 3

              Notes
              -----
              1. It was difficult to see any signal over the noise on the Spectrum
              display but the trace on the Waterfall was still distinct.
              2. No visible signal on the Spectrum, Waterfall becoming indistinct.
              3. Last traces of a signal still visible on the Waterfall.
              4. All measurements taken with an unmodulated carrier at 7.046MHz.
              5. Soundcard was a Crystal Fusion AC97 on the motherboard.
              6. Noise with no signal applied sits about the -100dB mark.
              7. Below -130dBm in it was hard to make out any audible tone but the
              waterfall display was still usable (probably only for slow morse).

              No measurements taken with Rocky yet but subjectively it looks
              pretty good. After doing a sweep with the signal generator (50 1kHz
              steps pausing for 1s at each step) to set the balance, image
              rejection is about 80dB.

              Hope this is useful.

              Rob, GM6OQN

              --- In softrock40@yahoogroups.com, "Rob Campbell" <gm6oqn@...> wrote:
              > --- In softrock40@yahoogroups.com, Bill Dumke <billd@> wrote:
              > >
              > > Rob,
              > >
              > > It would be interesting if you could use your signal generator
              to
              > make a
              > > standardized measurement of MDS looking for 3 dB (S+N)/N, then
              > noting
              > > the level you have going in from the generator. This will give
              > the
              > > noise floor of the SoftRock.
              > >
              > > Bill, WB5TCO
              > >
            • Jim Miller
              i think the conspiracists are on shakey ground. couldn t resist... back to my cypress fx2lp datasheet... 73 jim ab3cv ... From: To:
              Message 6 of 21 , Jun 1, 2006
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                i think the conspiracists are on "shakey" ground.

                couldn't resist...

                back to my cypress fx2lp datasheet...

                73

                jim ab3cv
                ----- Original Message -----
                From: <riese-k3djc@...>
                To: <softrock40@yahoogroups.com>
                Sent: Thursday, June 01, 2006 3:28 PM
                Subject: Re: [softrock40] phase noise


                right wing conspiracy

                K3DJC
                On Thu, 01 Jun 2006 13:17:23 -0500 KD5NWA <KD5NWA@...> writes:
                > According to some, phase noise and jitter is a vast conspiracy.
                >
                > At 11:49 AM 6/1/2006, Bill Dumke wrote:
                > >Francis,
                > >
                > >Thank you for posting that. Personally, I believe that is the
                > biggest
                > >single problem with these SDR type radios.
                > >
                > >Bill WB5TCO
                > >
                > >FRANCIS CARCIA wrote:
                > >
                > > > I just found a good article on measuring phase noise. I have
                > used the
                > > > one with a mixer and HP8640B. It is uploaded into the file area.
                > gfz
                > > >
                > > >
                > > > SPONSORED LINKS
                > > > Ham radio
                > > >
                > >
                >
                <http://groups.yahoo.com/gads?t=ms&k=Ham+radio&w1=Ham+radio&c=1&s=15&.sig
                =t8IpznzYq-E2LbCrDXaGPQ>
                >
                > >
                > > >
                > > >
                > > >
                > > >
                >
                ------------------------------------------------------------------------
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                > > > * Visit your group "softrock40
                > > > <http://groups.yahoo.com/group/softrock40>" on the web.
                > > >
                > > > * To unsubscribe from this group, send an email to:
                > > > softrock40-unsubscribe@yahoogroups.com
                > > >
                > <mailto:softrock40-unsubscribe@yahoogroups.com?subject=Unsubscribe>
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                > > > Service <http://docs.yahoo.com/info/terms/>.
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                > >
                > >
                > >
                > >Yahoo! Groups Links
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                > >
                >
                >
                > Cecil Bayona
                > KD5NWA
                > www.qrpradio.com
                >
                > "Windows, the most successful software virus ever" Don Seglio Batuna
                >
                >
                >
                >
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              • FRANCIS CARCIA
                I got similar numbers with my homebrew running about 500 hz. bw. Rob Campbell wrote: I managed to get a couple of hours after work today so
                Message 7 of 21 , Jun 1, 2006
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                  I got similar numbers with my homebrew running about 500 hz. bw.

                  Rob Campbell <gm6oqn@...> wrote:
                  I managed to get a couple of hours after work today so here are the
                  results of my testing so far:

                  Signal (dBm)   Winrad display (dB)   Comment
                  ------------   -------------------   -------
                  -32             0                    multiple harmonics visible
                  -32.2          -2                    S8
                  -40            -5                    S7
                  -50            -15                   S6
                  -60            -25                   S5
                  -70            -35                   S4
                  -80            -45                   S3
                  -90            -55                   S2
                  -100           -65                   S1/S2
                  -110           -75                   S1
                  -120           -85                   <S1
                  -130           -95                   see note 1 below
                  -134           -**                   see note 2
                  -135           -**                   see note 3

                  Notes
                  -----
                  1. It was difficult to see any signal over the noise on the Spectrum
                  display but the trace on the Waterfall was still distinct.
                  2. No visible signal on the Spectrum, Waterfall becoming indistinct.
                  3. Last traces of a signal still visible on the Waterfall.
                  4. All measurements taken with an unmodulated carrier at 7.046MHz.
                  5. Soundcard was a Crystal Fusion AC97 on the motherboard.
                  6. Noise with no signal applied sits about the -100dB mark.
                  7. Below -130dBm in it was hard to make out any audible tone but the
                  waterfall display was still usable (probably only for slow morse).

                  No measurements taken with Rocky yet but subjectively it looks
                  pretty good. After doing a sweep with the signal generator (50 1kHz
                  steps pausing for 1s at each step) to set the balance, image
                  rejection is about 80dB.

                  Hope this is useful.

                  Rob, GM6OQN

                  --- In softrock40@yahoogroups.com, "Rob Campbell" <gm6oqn@...> wrote:
                  > --- In softrock40@yahoogroups.com, Bill Dumke <billd@> wrote:
                  > >
                  > > Rob,
                  > >
                  > > It would be interesting if you could use your signal generator
                  to
                  > make a
                  > > standardized measurement of MDS looking for 3 dB (S+N)/N, then
                  > noting
                  > > the level you have going in from the generator.  This will give
                  > the
                  > > noise floor of the SoftRock.
                  > >
                  > > Bill, WB5TCO
                  > >






                • FRANCIS CARCIA
                  Nigel, I sent the daVinci code to the wrong place please send me a pm and I will try again. I deleted you mail so lost the address. frank Ford Peterson
                  Message 8 of 21 , Jun 1, 2006
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                    Nigel,
                    I sent the daVinci code to the wrong place please send me a pm and I will try again.
                    I deleted you mail so lost the address. frank

                    Ford Peterson <ford@...> wrote:
                    Bill wrote:

                    > Francis,
                    >
                    > Thank you for posting that. Personally, I believe that is the biggest
                    > single problem with these SDR type radios.
                    >
                    > Bill WB5TCO

                    "that is" being phase noise of course.

                    Actually, your comment is true, but not because of the "SDR type radios." These extremely simple receiver mixers are simply responding to the simply aweful Local Oscillators (by modern standards)that many of us are using to run the SR series mixers. Garbage-in / garbage-out as they say.

                    My personal view is that there is likely no substitute for the multi-conversion receiver. We have become accustomed to enjoying the ability to QSY from the AM broadcast band up to 440MHz (and higher) with the touch of a button on most modern radios. I can see using an SDR type of mixer to acquire base-band data, and replace a large segment of a traditional radio using the sound card. But performance will be lack-luster at best when you QSY to any upper band without first performing a block-conversion of that band using traditional mixers and LOs. There is likely no substitute for traditional block conversion down to a reasonable frequency for the SDR to deal with. If you want real performance, then the focus of attention should be on the LO. Clean, frequency agile, spurious free, low-phase noise LOs is the name of the game. Use these nifty detectors as the final conversion from a relatively low frequency IF to your ears--and make that LO pristine clean of course.

                    Ford-N0FP
                    ford@...




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                  • Alberto I2PHD
                    ... Something went in saturation above -40 dBm....probably the opamps or the sound card. 73 Alberto I2PHD
                    Message 9 of 21 , Jun 1, 2006
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                      > Signal (dBm) Winrad display (dB) Comment
                      > ------------ ------------------- -------
                      > -32 0 multiple harmonics visible
                      > -32.2 -2 S8
                      > -40 -5 S7
                      > -50 -15 S6
                      > -60 -25 S5
                      ---- snip ----

                      Something went in saturation above -40 dBm....probably the opamps or the sound card.

                      73 Alberto I2PHD
                    • Bill Tracey
                      Probably the sound card started saturating above -40 dbm -- the SR 6 hardware I ve measured will produce a 4.5Vpp signal with a -18 dbm input signal on 7 MHz.
                      Message 10 of 21 , Jun 1, 2006
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                        Probably the sound card started saturating above -40 dbm -- the SR 6
                        hardware I've measured will produce a 4.5Vpp signal with a -18 dbm input
                        signal on 7 MHz. Suspect the sound card saturates long before that.

                        Cheers,

                        Bill (kd5tfd)

                        At 06:48 PM 6/1/2006, Alberto I2PHD wrote:
                        > > Signal (dBm) Winrad display (dB) Comment
                        > > ------------ ------------------- -------
                        > > -32 0 multiple harmonics visible
                        > > -32.2 -2 S8
                        > > -40 -5 S7
                        > > -50 -15 S6
                        > > -60 -25 S5
                        >---- snip ----
                        >
                        >Something went in saturation above -40 dBm....probably the opamps or the
                        >sound card.
                        >
                        >73 Alberto I2PHD
                      • FRANCIS CARCIA
                        That is what I found. The OP amp gain jacks the signal to sound card saturation. Bill Tracey wrote: Probably the sound card started
                        Message 11 of 21 , Jun 1, 2006
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                          That is what I found. The OP amp gain jacks the signal to sound card saturation.

                          Bill Tracey <kd5tfd@...> wrote:
                          Probably the sound card started saturating above -40 dbm -- the SR 6
                          hardware I've measured will produce a 4.5Vpp signal with a -18 dbm input
                          signal  on 7 MHz.  Suspect the sound card saturates long before that.

                          Cheers,

                          Bill (kd5tfd)

                          At 06:48 PM 6/1/2006, Alberto I2PHD wrote:
                          > > Signal (dBm)   Winrad display (dB)   Comment
                          > > ------------   -------------------   -------
                          > > -32             0                    multiple harmonics visible
                          > > -32.2          -2                    S8
                          > > -40            -5                    S7
                          > > -50            -15                   S6
                          > > -60            -25                   S5
                          >---- snip ----
                          >
                          >Something went in saturation above -40 dBm....probably the opamps or the
                          >sound card.
                          >
                          >73  Alberto  I2PHD




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                        • Sparkes, John
                          Well, according to ONE, anyway...!________________________________From: softrock40@yahoogroups.com [mailto:softrock40@yahoogroups.com] On Behalf Of KD5NWA
                          Message 12 of 21 , Jun 1, 2006
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                            Well, according to ONE, anyway...!


                            From: softrock40@yahoogroups.com [mailto:softrock40@yahoogroups.com] On Behalf Of KD5NWA
                            Sent: Friday, 2 June 2006 02:17
                            To: softrock40@yahoogroups.com
                            Cc: softrock40@yahoogroups.com
                            Subject: Re: [softrock40] phase noise

                            According to some, phase noise and jitter is a vast conspiracy.

                            At 11:49 AM 6/1/2006, Bill Dumke wrote:
                            >Francis,
                            >
                            >Thank you for posting that. 
                            Personally, I believe that is the biggest
                            >single problem with these SDR
                            type radios.
                            >
                            >Bill  WB5TCO
                            >
                            >FRANCIS CARCIA
                            wrote:
                            >
                            > > I just found a good article on measuring phase
                            noise. I have used the
                            > > one with a mixer and HP8640B. It is uploaded
                            into the file area.  gfz
                            > >
                            > >
                            > > SPONSORED
                            LINKS
                            > > Ham radio
                            > >
                            > <
                            href="http://groups.yahoo.com/gads?t=ms&k=Ham+radio&w1=Ham+radio&c=1&s=15&.sig=t8IpznzYq-E2LbCrDXaGPQ">http://groups.yahoo.com/gads?t=ms&k=Ham+radio&w1=Ham+radio&c=1&s=15&.sig=t8IpznzYq-E2LbCrDXaGPQ>
                            >
                            > >
                            > >
                            > >
                            > >
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                            Cecil Bayona
                            KD5NWA
                            www.qrpradio.com

                            "Windows, the most successful software virus ever" Don Seglio Batuna


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                          • Robert Campbell
                            Thanks, guys. Looks like the perfomance is OK and I haven t messed up in construction. I figured the harmonics were down to overdriving the soundcard input.
                            Message 13 of 21 , Jun 2, 2006
                            • 0 Attachment
                              Thanks, guys.

                              Looks like the perfomance is OK and I haven't messed
                              up in construction. I figured the harmonics were down
                              to overdriving the soundcard input.

                              Just need to see what it does with an antenna now :-)

                              Rob GM6OQN

                              --- FRANCIS CARCIA <carcia@...> wrote:

                              > That is what I found. The OP amp gain jacks the
                              > signal to sound card saturation.
                              >
                              > Bill Tracey <kd5tfd@...> wrote: Probably the
                              > sound card started saturating above -40 dbm -- the
                              > SR 6
                              > hardware I've measured will produce a 4.5Vpp signal
                              > with a -18 dbm input
                              > signal on 7 MHz. Suspect the sound card saturates
                              > long before that.
                              >
                              > Cheers,
                              >
                              > Bill (kd5tfd)
                              >
                              > At 06:48 PM 6/1/2006, Alberto I2PHD wrote:
                              > > > Signal (dBm) Winrad display (dB) Comment
                              > > > ------------ ------------------- -------
                              > > > -32 0 multiple
                              > harmonics visible
                              > > > -32.2 -2 S8
                              > > > -40 -5 S7
                              > > > -50 -15 S6
                              > > > -60 -25 S5
                              > >---- snip ----
                              > >
                              > >Something went in saturation above -40
                              > dBm....probably the opamps or the
                              > >sound card.
                              > >
                              > >73 Alberto I2PHD
                              >
                              >
                              >
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