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Re: [softrock40] SoftRock V7 beta pics and spectum shots

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  • John H. Fisher
    Beautiful job, Bill, as always :-) Thanks for sharing :-) ... -- Regards, John ========================================================= email:
    Message 1 of 19 , Apr 1 5:15 PM
      Beautiful job, Bill, as always :-) Thanks for sharing :-)

      Bill Tracey wrote:
      > Got a SoftRock V7 beta built and checked out today - looks pretty
      > good. MDS of -112 dbm with a Delta 44 and -109 dbm with an Extigy. Pics
      > and PowerSDR spec shots @
      > http://ewjt.com/kd5tfd/sdr1k-notebook/sr40/sr7/index.html
      >
      > Cheers,
      >
      > Bill (kd5tfd)
      >
      >
      >
      --
      Regards,
      John

      =========================================================
      email: k5jhf@...
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      =========================================================
    • Bill Tracey
      I think there are a number of approaches one could take here -- simple diversity would allow one to pick the receiver with the strongest signal and use it.
      Message 2 of 19 , Apr 1 5:23 PM
        I think there are a number of approaches one could take here -- simple
        diversity would allow one to pick the receiver with the strongest signal
        and use it. Cooler would be to combine the output of all the receivers
        together with the correct phase relationship to get some gain out of having
        all of the antennas. To do this I think one would need to clock all the
        SoftRocks from a single oscillator and clock all the A/D converters from a
        single master clock and do a little software to combine the signals with
        correct phase relationship. Beyond my DSP capabilities at the moment, but
        maybe someday. Certainly within the realm of possibilities.

        I'd not plan on doing something like this with off the shelf sound
        cards. There's currently some work going on to build an FPGA based USB
        connected hi quality sound card for SDR as part of the High Performance SDR
        project (http://hpsdr.org/index.html). The A/D D/A board for this guy is
        known as the Janus baord ( http://hpsdr.org/janus.html ). At the moment
        it's a 4 channel in 4 channel out configuration similar to the Delta
        44. Adding additional A/D converters on the input side to deal with
        multiple receivers should not be terribly difficult.

        All of this stuff is in the very early prototype stages. Don't know if
        there's anyone on the HPSDR crew currently thinking of multiple RX
        configurations .... if not we probably should think of such a configuration.

        Cheers.

        Bill (kd5tfd)


        At 12:08 PM 4/1/2006, n6rk wrote:
        >Just joined the group. I would like to connect 4 to 6 SoftRock
        >receivers to individual antennas and do some kind of diversity
        >receiver. A couple of questions arise. First, can I use a hardware
        >image rejection filter ahead of the SoftRock, and thereby only have
        >to digitize I (and not Q)? This halves the number of sound card
        >inputs required. Second, how many independent input channels
        >(with their own A/D's) do the Delta 44 and Delta 66 cards have?
        >I can't penetrate the marketing literature that assumes you are
        >doing music recording and want to mix the inputs together and then
        >digitize. I would like to believe the Delta 66 actually has 6
        >independent inputs allowing 6 SoftRocks using I only. Can I run
        >multiple instances of Rocky? To bring out the audio, I would probably
        >use some cheap sound card(s). It seems to be very easy to get lots of
        >DAC's on a card intended to do surround sound.
        >
        >73 Rick N6RK
      • Tony Parks
        Very good Bill! Thanks for making the performance data measurements on the v7.0 SoftRock and sharing the nice pictures. All of the v7.0 kit orders have been
        Message 3 of 19 , Apr 1 7:09 PM
          Very good Bill! Thanks for making the performance data measurements on the
          v7.0 SoftRock and sharing the nice pictures.

          All of the v7.0 kit orders have been filled with most of the kits in the
          mail. Those not in the mail are packed and will go out on April 3.

          Several orders for built v7.0 receivers will be filled in the next tens
          days.

          After filling all orders and setting aside the kits for the build orders, I
          find I have still three v7.0 kits that can be sold. If you would like one
          of the three kits, check with me before placing a PayPal order and I will
          let you know if one of the kits can be yours. I am asking $20 for a v7.0
          SoftRock kit which includes postage costs.

          73,
          Tony KB9YIG

          ----- Original Message -----
          From: "Bill Tracey" <kd5tfd@...>
          To: <softrock40@yahoogroups.com>
          Sent: Saturday, April 01, 2006 7:52 PM
          Subject: [softrock40] SoftRock V7 beta pics and spectum shots


          > Got a SoftRock V7 beta built and checked out today - looks pretty
          > good. MDS of -112 dbm with a Delta 44 and -109 dbm with an Extigy. Pics
          > and PowerSDR spec shots @
          > http://ewjt.com/kd5tfd/sdr1k-notebook/sr40/sr7/index.html
          >
          > Cheers,
          >
          > Bill (kd5tfd)
          >
          >
          >
          >
          >
          > Yahoo! Groups Links
          >
          >
          >
          >
          >
          >
        • FRANCIS CARCIA
          Bill, What do you consider MDS. We should work to a standard like 3 dB increase in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much does mds
          Message 4 of 19 , Apr 2 5:37 PM
            Bill,
            What do you consider MDS. We should work to a standard like 3 dB increase in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much does mds improve with CW filter selected? frank WA1GFZ (waiting for santa to arrive) 

            Tony Parks <raparks@...> wrote:
            Very good Bill!   Thanks for making the performance data measurements on the
            v7.0 SoftRock and sharing the nice pictures.

            All of the v7.0 kit orders have been filled with most of the kits in the
            mail.  Those not in the mail are packed and will go out on April 3.

            Several orders for built v7.0 receivers will be filled in the next tens
            days.

            After filling all orders and setting aside the kits for the build orders, I
            find I have still three v7.0 kits that can be sold.  If you would like one
            of the three kits, check with me before placing a PayPal order and I will
            let you know if one of the kits can be yours.  I am asking $20 for a v7.0
            SoftRock kit which includes postage costs.

            73,
            Tony KB9YIG

            ----- Original Message -----
            From: "Bill Tracey" <kd5tfd@...>
            To: <softrock40@yahoogroups.com>
            Sent: Saturday, April 01, 2006 7:52 PM
            Subject: [softrock40] SoftRock V7 beta pics and spectum shots


            > Got a SoftRock V7 beta built and checked out today  - looks pretty
            > good.  MDS of -112 dbm with a Delta 44 and -109 dbm with an Extigy.  Pics
            > and PowerSDR spec shots @
            > http://ewjt.com/kd5tfd/sdr1k-notebook/sr40/sr7/index.html
            >
            > Cheers,
            >
            > Bill (kd5tfd)
            >
            >
            >
            >
            >
            > Yahoo! Groups Links
            >
            >
            >
            >
            >
            >


          • FRANCIS CARCIA
            Rick, I m using a Racal RA6830 as a front end for SDR. The Racal has dual 20 KHz roofing filters. I plan to run it against the soft rock 6 on 75 meters soon. i
            Message 5 of 19 , Apr 2 5:47 PM
              Rick,
              I'm using a Racal RA6830 as a front end for SDR. The Racal has dual 20 KHz roofing filters. I plan to run it against the soft rock 6 on 75 meters soon. i am not limited to a small section of a band since the SDR (I) is at the 455 KHz second IF frequency.
              frank WA1GFZ

              n6rk <richard@...> wrote:
              Just joined the group.  I would like to connect 4 to 6 SoftRock
              receivers to individual antennas and do some kind of diversity
              receiver.  A couple of questions arise.  First, can I use a hardware
              image rejection filter ahead of the SoftRock, and thereby only have
              to digitize I (and not Q)?  This halves the number of sound card
              inputs required.  Second, how many independent input channels
              (with their own A/D's) do the Delta 44 and Delta 66 cards have?
              I can't penetrate the marketing literature that assumes you are
              doing music recording and want to mix the inputs together and then
              digitize.  I would like to believe the Delta 66 actually has 6
              independent inputs allowing 6 SoftRocks using I only.  Can I run
              multiple instances of Rocky?  To bring out the audio, I would probably
              use some cheap sound card(s).  It seems to be very easy to get lots of
              DAC's on a card intended to do surround sound.

              73 Rick N6RK




            • Bill Dumke
              Also I was wondering how you even did it? Here with my SoftRock 40 and Rocky 1.41, when I connect it to a 50 Ohm load, rather than the antenna with a lot of
              Message 6 of 19 , Apr 2 5:52 PM
                Also I was wondering how you even did it? Here with my SoftRock 40 and
                Rocky 1.41, when I connect it to a 50 Ohm load, rather than the antenna
                with a lot of atmospheric noise on 40 meters, I see a lot of spurious
                signals throughout the whole Rocky bandpass. It appears the digital ALC
                in Rocky is causing this. If you turn it the ALC on the front panel of
                Rocky it still does this, although the audio level heard in the speakers
                can now be adjusted manually in that case. Did you find a clean "hole"
                somewhere to get the reading.

                Please describe the test system you were using and how you did it.

                I wish Rocky could be modified to use just a fixed DSP gain as a
                setting, so that Sun and sky noise measurements could be made to check
                the receiver noise temperature of the VHF/UHF & microwave receive
                systems. This is NOW important with SoftRock v7.0 which is intended for
                VHF converters.

                Bill WB5TCO

                FRANCIS CARCIA wrote:

                > Bill,
                > What do you consider MDS. We should work to a standard like 3 dB
                > increase in audio or 10 dB S+N/N also I see you have 10 KHz selected.
                > How much does mds improve with CW filter selected? frank WA1GFZ
                > (waiting for santa to arrive)
                >
                > */Tony Parks <raparks@...>/* wrote:
                >
                > Very good Bill! Thanks for making the performance data
                > measurements on the
                > v7.0 SoftRock and sharing the nice pictures.
                >
                > All of the v7.0 kit orders have been filled with most of the kits
                > in the
                > mail. Those not in the mail are packed and will go out on April 3.
                >
                > Several orders for built v7.0 receivers will be filled in the next
                > tens
                > days.
                >
                > After filling all orders and setting aside the kits for the build
                > orders, I
                > find I have still three v7.0 kits that can be sold. If you would
                > like one
                > of the three kits, check with me before placing a PayPal order and
                > I will
                > let you know if one of the kits can be yours. I am asking $20 for
                > a v7.0
                > SoftRock kit which includes postage costs.
                >
                > 73,
                > Tony KB9YIG
                >
                > ----- Original Message -----
                > From: "Bill Tracey" <kd5tfd@...>
                > To: <softrock40@yahoogroups.com>
                > Sent: Saturday, April 01, 2006 7:52 PM
                > Subject: [softrock40] SoftRock V7 beta pics and spectum shots
                >
                >
                > > Got a SoftRock V7 beta built and checked out today - looks pretty
                > > good. MDS of -112 dbm with a Delta 44 and -109 dbm with an
                > Extigy. Pics
                > > and PowerSDR spec shots @
                > > http://ewjt.com/kd5tfd/sdr1k-notebook/sr40/sr7/index.html
                > >
                > > Cheers,
                > >
                > > Bill (kd5tfd)
                > >
                > >
                > >
                > >
                > >
                > > Yahoo! Groups Links
                > >
                > >
                > >
                > >
                > >
                > >
                >
                >
                >
                > ------------------------------------------------------------------------
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                > <http://groups.yahoo.com/group/softrock40>" on the web.
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              • Bill Tracey
                Actually the spectrum screen shots do not match the MDS measurement -- they were for a -54 dbm input, just trying to show the level of spurs and gunk I m
                Message 7 of 19 , Apr 2 6:07 PM
                  Actually the spectrum screen shots do not match the MDS measurement -- they
                  were for a -54 dbm input, just trying to show the level of spurs and gunk
                  I'm seeing.

                  The MDS definition I'm using is 3 db above the noise floor in a 500 hz
                  bandwidth, The measurement is done as follows:

                  Connect SoftRock and sound card. Apply -60 dbm signal from signal
                  generator approx 12 khz above osc freq of SoftRock. Null image, calibrate
                  level. Set PowerSDR for CW mode, 500 hz bandwidth. Turn off RF on signal
                  generator. Note avg singal strength reading on S Meter - call this
                  measurement A. Turn on signal generator - adjust level until avg signal
                  strength on S meter reads 3db above measurement A. Note amplitude level on
                  signal generator - this is what I call MDS.

                  Signal generator I'm using is an HP 8656b -- it's not been calibrated in a
                  few years,. however does seem to be accurate for level when compared to an
                  Elecraft XG2 which is the closest thing I've got to a calibrated level.

                  Credit for the methodology of doing the measurement goes to Phil Harman -
                  VK6APH who explained to me how to do it.

                  Cheers,

                  Bill (kd5tfd)

                  At 07:37 PM 4/2/2006, you wrote:
                  >Bill,
                  >What do you consider MDS. We should work to a standard like 3 dB increase
                  >in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much does
                  >mds improve with CW filter selected? frank WA1GFZ (waiting for santa to
                  >arrive)
                • Bill Dumke
                  Bill, So the PowerSDR software will allow for a fixed system gain, by turning off the AGC? That makes it more appropriate for us weak signal types, as opposed
                  Message 8 of 19 , Apr 2 6:16 PM
                    Bill,

                    So the PowerSDR software will allow for a fixed system gain, by turning
                    off the AGC?

                    That makes it more appropriate for us weak signal types, as opposed to
                    the current version of Rocky, for looking at Sun to Sky noise temperature.

                    The method you used looks good to me.

                    Bill WB5TCO

                    Bill Tracey wrote:

                    > Actually the spectrum screen shots do not match the MDS measurement --
                    > they
                    > were for a -54 dbm input, just trying to show the level of spurs and gunk
                    > I'm seeing.
                    >
                    > The MDS definition I'm using is 3 db above the noise floor in a 500 hz
                    > bandwidth, The measurement is done as follows:
                    >
                    > Connect SoftRock and sound card. Apply -60 dbm signal from signal
                    > generator approx 12 khz above osc freq of SoftRock. Null image,
                    > calibrate
                    > level. Set PowerSDR for CW mode, 500 hz bandwidth. Turn off RF on
                    > signal
                    > generator. Note avg singal strength reading on S Meter - call this
                    > measurement A. Turn on signal generator - adjust level until avg signal
                    > strength on S meter reads 3db above measurement A. Note amplitude
                    > level on
                    > signal generator - this is what I call MDS.
                    >
                    > Signal generator I'm using is an HP 8656b -- it's not been calibrated
                    > in a
                    > few years,. however does seem to be accurate for level when compared
                    > to an
                    > Elecraft XG2 which is the closest thing I've got to a calibrated level.
                    >
                    > Credit for the methodology of doing the measurement goes to Phil Harman -
                    > VK6APH who explained to me how to do it.
                    >
                    > Cheers,
                    >
                    > Bill (kd5tfd)
                    >
                    > At 07:37 PM 4/2/2006, you wrote:
                    > >Bill,
                    > >What do you consider MDS. We should work to a standard like 3 dB
                    > increase
                    > >in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much
                    > does
                    > >mds improve with CW filter selected? frank WA1GFZ (waiting for santa to
                    > >arrive)
                    >
                    >
                    >
                    >
                    > 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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                  • Bill Dumke
                    Bill, Which version of PowerSDR were you using? Also have you tried the same measurement on a SoftRock 40 or any of the other SoftRock versions? It would be
                    Message 9 of 19 , Apr 2 6:23 PM
                      Bill,

                      Which version of PowerSDR were you using?

                      Also have you tried the same measurement on a SoftRock 40 or any of the
                      other SoftRock versions?

                      It would be interesting to see what results you have on the other bands
                      to compare the SoftRock v7.0 performance.

                      Bill WB5TCO

                      Bill Dumke wrote:

                      >Bill,
                      >
                      >So the PowerSDR software will allow for a fixed system gain, by turning
                      >off the AGC?
                      >
                      >That makes it more appropriate for us weak signal types, as opposed to
                      >the current version of Rocky, for looking at Sun to Sky noise temperature.
                      >
                      >The method you used looks good to me.
                      >
                      >Bill WB5TCO
                      >
                      >Bill Tracey wrote:
                      >
                      >
                      >
                      >>Actually the spectrum screen shots do not match the MDS measurement --
                      >>they
                      >>were for a -54 dbm input, just trying to show the level of spurs and gunk
                      >>I'm seeing.
                      >>
                      >>The MDS definition I'm using is 3 db above the noise floor in a 500 hz
                      >>bandwidth, The measurement is done as follows:
                      >>
                      >>Connect SoftRock and sound card. Apply -60 dbm signal from signal
                      >>generator approx 12 khz above osc freq of SoftRock. Null image,
                      >>calibrate
                      >>level. Set PowerSDR for CW mode, 500 hz bandwidth. Turn off RF on
                      >>signal
                      >>generator. Note avg singal strength reading on S Meter - call this
                      >>measurement A. Turn on signal generator - adjust level until avg signal
                      >>strength on S meter reads 3db above measurement A. Note amplitude
                      >>level on
                      >>signal generator - this is what I call MDS.
                      >>
                      >>Signal generator I'm using is an HP 8656b -- it's not been calibrated
                      >>in a
                      >>few years,. however does seem to be accurate for level when compared
                      >>to an
                      >>Elecraft XG2 which is the closest thing I've got to a calibrated level.
                      >>
                      >>Credit for the methodology of doing the measurement goes to Phil Harman -
                      >>VK6APH who explained to me how to do it.
                      >>
                      >>Cheers,
                      >>
                      >>Bill (kd5tfd)
                      >>
                      >>At 07:37 PM 4/2/2006, you wrote:
                      >>
                      >>
                      >>>Bill,
                      >>>What do you consider MDS. We should work to a standard like 3 dB
                      >>>
                      >>>
                      >>increase
                      >>
                      >>
                      >>>in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much
                      >>>
                      >>>
                      >>does
                      >>
                      >>
                      >>>mds improve with CW filter selected? frank WA1GFZ (waiting for santa to
                      >>>arrive)
                      >>>
                      >>>
                      >>
                      >>
                      >>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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                    • FRANCIS CARCIA
                      I prefer to monitor recovered audio with an RMS volt meter. fc Bill Dumke wrote: Bill, So the PowerSDR software will allow for a fixed
                      Message 10 of 19 , Apr 2 6:31 PM
                        I prefer to monitor recovered audio with an RMS volt meter.
                        fc

                        Bill Dumke <billd@...> wrote:
                        Bill,

                        So the PowerSDR software will allow for a fixed system gain, by turning
                        off the AGC?

                        That makes it more appropriate for us weak signal types, as opposed to
                        the current version of Rocky, for looking at Sun to Sky noise temperature.

                        The method you used looks good to me.

                        Bill WB5TCO

                        Bill Tracey wrote:

                        > Actually the spectrum screen shots do not match the MDS measurement --
                        > they
                        > were for a -54 dbm input, just trying to show the level of spurs and gunk
                        > I'm seeing.
                        >
                        > The MDS definition I'm using is 3 db above the noise floor in a 500 hz
                        > bandwidth, The measurement is done as follows:
                        >
                        > Connect SoftRock and sound card. Apply -60 dbm signal from signal
                        > generator approx 12 khz above osc freq of SoftRock. Null image,
                        > calibrate
                        > level. Set PowerSDR for CW mode, 500 hz bandwidth. Turn off RF on
                        > signal
                        > generator. Note avg singal strength reading on S Meter - call this
                        > measurement A. Turn on signal generator - adjust level until avg signal
                        > strength on S meter reads 3db above measurement A. Note amplitude
                        > level on
                        > signal generator - this is what I call MDS.
                        >
                        > Signal generator I'm using is an HP 8656b -- it's not been calibrated
                        > in a
                        > few years,. however does seem to be accurate for level when compared
                        > to an
                        > Elecraft XG2 which is the closest thing I've got to a calibrated level.
                        >
                        > Credit for the methodology of doing the measurement goes to Phil Harman -
                        > VK6APH who explained to me how to do it.
                        >
                        > Cheers,
                        >
                        > Bill (kd5tfd)
                        >
                        > At 07:37 PM 4/2/2006, you wrote:
                        > >Bill,
                        > >What do you consider MDS. We should work to a standard like 3 dB
                        > increase
                        > >in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much
                        > does
                        > >mds improve with CW filter selected? frank WA1GFZ (waiting for santa to
                        > >arrive)
                        >
                        >
                        >
                        >
                        > SPONSORED LINKS
                        > Ham radio
                        >
                        >
                        >
                        >
                        > ------------------------------------------------------------------------
                        > YAHOO! GROUPS LINKS
                        >
                        > * Visit your group "softrock40
                        > " on the web.
                        >
                        > * To unsubscribe from this group, send an email to:
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                      • FRANCIS CARCIA
                        -109 dBM MDS is not that great for above 20 meter work. I wonder if the op amp gain needs to increase. Does the background noise come up on the spectrum
                        Message 11 of 19 , Apr 2 6:42 PM
                          -109 dBM MDS is not that great for above 20 meter work. I wonder if the op amp gain needs to increase. Does the background noise come up on the spectrum display when the V7 is connected without an antenna. Do you know what level input saturates the sound card making spure. IE dynamic range? I use a pair of HP8640Bs myself.
                          I like to see a mds lower than -125 dBm above 14 MHz. I usually set a RA6830 to -130 dBM and that has just enough MDS for 10 meters. Might need a preamplifier...fc

                          Bill Tracey <kd5tfd@...> wrote:
                          Actually the spectrum screen shots do not match the MDS measurement -- they
                          were for a -54 dbm input, just trying to show the level of spurs and gunk
                          I'm seeing.

                          The MDS definition I'm using is 3 db above the noise floor in a 500 hz
                          bandwidth,  The measurement is done as follows:

                          Connect SoftRock and sound card.  Apply -60 dbm signal from signal
                          generator approx 12 khz above osc freq of SoftRock.   Null image, calibrate
                          level.  Set PowerSDR for CW mode, 500 hz bandwidth.  Turn off RF on signal
                          generator.  Note avg singal strength reading on S Meter - call this
                          measurement A.  Turn on signal generator - adjust level until avg signal
                          strength on S meter reads 3db above measurement A.  Note amplitude level on
                          signal generator - this is what I call MDS.

                          Signal generator I'm using is an HP 8656b  -- it's not been calibrated in a
                          few years,. however does seem to be accurate for level when compared to an
                          Elecraft XG2 which is the closest thing I've got to a calibrated level.

                          Credit for the methodology of doing the measurement goes to Phil Harman -
                          VK6APH who explained to me how to do it.

                          Cheers,

                          Bill (kd5tfd)

                          At 07:37 PM 4/2/2006, you wrote:
                          >Bill,
                          >What do you consider MDS. We should work to a standard like 3 dB increase
                          >in audio or 10 dB S+N/N also I see you have 10 KHz selected. How much does
                          >mds improve with CW filter selected? frank WA1GFZ (waiting for santa to
                          >arrive)



                        • Bill Tracey
                          PowerSDR does allow you to turn off the AGC and set a fixed gain - although I did not do that on this these measurements and don t think it matters as I
                          Message 12 of 19 , Apr 2 9:45 PM
                            PowerSDR does allow you to turn off the AGC and set a fixed gain - although
                            I did not do that on this these measurements and don't think it matters as
                            I believe the signal strength is computed before the AGC is applied. Next
                            time I do some measurements I'll play around and see if the AGC setting
                            makes any difference.

                            Regards,

                            Bill (kd5tfd)


                            At 08:16 PM 4/2/2006, Bill Dumke wrote:
                            >Bill,
                            >
                            >So the PowerSDR software will allow for a fixed system gain, by turning
                            >off the AGC?
                            >
                            >That makes it more appropriate for us weak signal types, as opposed to
                            >the current version of Rocky, for looking at Sun to Sky noise temperature.
                            >
                            >The method you used looks good to me.
                            >
                            >Bill WB5TCO
                          • Ross Stenberg
                            In looking through the archives, I m confused to the MDS of v4 5,6,and 7 as measured with the same methodology. Does anyone have those figures? Thanks and 73,
                            Message 13 of 19 , Apr 3 9:45 AM
                              In looking through the archives, I'm confused to the MDS of v4 5,6,and 7 as measured with the same methodology. Does anyone have those figures?
                               
                              Thanks and 73,
                              Ross K9COX
                               


                            • KD5NWA
                              It s going to vary according to what sound card, and the bit resolution you take the measurement with. ... Cecil Bayona KD5NWA www.qrpradio.com I fail to see
                              Message 14 of 19 , Apr 3 10:51 AM
                                It's going to vary according to what sound card, and the bit resolution you take the measurement with.

                                At 11:45 AM 4/3/2006, you wrote:
                                In looking through the archives, I'm confused to the MDS of v4 5,6,and 7 as measured with the same methodology. Does anyone have those figures?
                                 
                                Thanks and 73,
                                Ross K9COX
                                 




                                YAHOO! GROUPS LINKS




                                Cecil Bayona
                                KD5NWA
                                www.qrpradio.com

                                I fail to see why doing the same thing over and over and getting the same results every time is insanity: I've almost proved it isn't; only a few more tests now and I'm sure results will differ this time ...

                              • Ross Stenberg
                                Thanks, but how about all versions used with the same 24 bit, good dynamic range, low noise, quality sound card such as the Delta 44 or similar; or any such
                                Message 15 of 19 , Apr 3 12:41 PM
                                  Thanks, but how about all versions used with the same 24 bit, good dynamic range, low noise, quality sound card such as the Delta 44 or similar; or any such card as long as we are comparing apples to apples?


                                  From: softrock40@yahoogroups.com [mailto:softrock40@yahoogroups.com] On Behalf Of KD5NWA
                                  Sent: Monday, April 03, 2006 12:51 PM
                                  To: softrock40@yahoogroups.com
                                  Subject: Re: [softrock40] MDS of various versions

                                  It's going to vary according to what sound card, and the bit resolution you take the measurement with.

                                  At 11:45 AM 4/3/2006, you wrote:
                                  In looking through the archives, I'm confused to the MDS of v4 5,6,and 7 as measured with the same methodology. Does anyone have those figures?
                                   
                                  Thanks and 73,
                                  Ross K9COX
                                   




                                  YAHOO! GROUPS LINKS




                                  Cecil Bayona
                                  KD5NWA
                                  www.qrpradio.com

                                  I fail to see why doing the same thing over and over and getting the same results every time is insanity: I've almost proved it isn't; only a few more tests now and I'm sure results will differ this time ...

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