Loading ...
Sorry, an error occurred while loading the content.

Switching power supplies

Expand Messages
  • Preston Douglas
    This is a general question about SDR rigs and switching power supplies. One of my linear 12v supplies was drowned in a basement flood thanks to hurricane
    Message 1 of 11 , Oct 21, 2011
    • 0 Attachment
      This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter?  


      Preston WJ2V
    • vbifyz
      I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum. I ve found
      Message 2 of 11 , Oct 21, 2011
      • 0 Attachment
        I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum.
        I've found one switching PS 12V/2A that is quiet above 10MHz. Using it with my FT-817.

        As for RX Softrocks, the smallest linear wall warts (100-150mA) seem to give the best results. They are also usually free or 25c at garage sales.
        The RX lineup has a 7805 regulator, so the supply doesn't have to be regulated.

        73, Mike

        --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
        >
        > This is a general question about SDR rigs and switching power supplies. One of my linear 12v supplies was drowned in a basement flood thanks to hurricane Irene. I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply. One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it. It would be safer up on the desk. So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter?
        >
        >
        >
        > Preston WJ2V
        >
      • Richard
        On Fri, 21 Oct 2011 16:08:38 -0400 (EDT) ... There are two definitions that I always remember. A synthesiser is a device to produce all frequencies but one of
        Message 3 of 11 , Oct 21, 2011
        • 0 Attachment
          On Fri, 21 Oct 2011 16:08:38 -0400 (EDT)
          Preston Douglas <pdouglas12@...> wrote:

          > This is a general question about SDR rigs and switching power supplies. One of my linear 12v supplies
          > was drowned in a basement flood thanks to hurricane Irene. I am thinking of replacing it with a
          > small switching supply from MFJ, particularly since it can sit on the operating desk without stressing
          > it with the weight of an equivalent linear supply. One of the reasons I lost the linear supply was
          > that it was mounted on a shelf near the floor, so the water reached it. It would be safer up on the
          > desk. So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so,
          > are you getting a lot of hash on the panadapter?
          >
          >
          >
          > Preston WJ2V
          >

          There are two definitions that I always remember.
          A synthesiser is a device to produce all frequencies but one of greater amplitude than the rest.

          A switch mode PSU is a device to produce all frequencies at the same greater amplitude.

          Caveat Emptor

          --
          Best wishes / 73
          Richard Bown

          e-mail: richard@... or richard.bown@...

          nil carborundum a illegitemis
          ##################################################################################
          Ham Call G8JVM . OS Debian Wheezy amd64 on a Dual core AMD Athlon 5200, 4 GB RAM
          Maidenhead QRA: IO82SP38, LAT. 52 39.720' N LONG. 2 28.171 W ( degs mins )
          QRV HF + VHF Microwave 23 cms:140W,13 cms:100W,6 cms:10W & 3 cms:5W
          ##################################################################################
        • cbayona
          The answer varies all over the place, some are very quiet some are horrible, and some are in-between. I own several Samlex 25A power supplies out of 5 one was
          Message 4 of 11 , Oct 21, 2011
          • 0 Attachment
            The answer varies all over the place, some are very quiet some are horrible, and some are in-between.

            I own several Samlex 25A power supplies out of 5 one was noisy, the others were pretty quiet, so I took all 5 apart and the wires heading for the output connectors were wound around a large Ferrite core with multiple size capacitors to ground (.001uF, .01uF, and .1uF of good quality) all five are quiet as a church mouse.

            On the other hand my Dell laptop when running on batteries can be heard all over the spectrum, while plugged in it's not too bad.

            At 04:49 PM 10/21/2011, you wrote:
            I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum.
            I've found one switching PS 12V/2A that is quiet above 10MHz. Using it with my FT-817.

            As for RX Softrocks, the smallest linear wall warts (100-150mA) seem to give the best results. They are also usually free or 25c at garage sales.
            The RX lineup has a 7805 regulator, so the supply doesn't have to be regulated.

            73, Mike

            --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
            >
            > This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter? 
            >
            >
            >
            > Preston WJ2V
            >

            Cecil
            k5nwa
            http://www.softrockradio.org/ > <  http://thepartsplace.k5nwa.com/ >
            http://parts.softrockradio.org/ >

            Never take life seriously. Nobody gets out alive anyway.

          • The Silver Fox
            Switching power supplies generally use radio frequencies to manage the voltage and amperage exchange. I assume that good ones have decent filters to keep the
            Message 5 of 11 , Oct 21, 2011
            • 0 Attachment

              Switching power supplies generally use radio frequencies to manage the voltage and amperage exchange.  I assume that good ones have decent filters to keep the interference to a minimum.  If they radiated a lot you would hear it in your computer sound system.  The only caveat is that the softrock radios are sensitive and they also are reliant on the computer sound system.

              73’s

              Alan – W6ARH

               

              From: softrock40@yahoogroups.com [mailto:softrock40@yahoogroups.com] On Behalf Of cbayona
              Sent: Friday, October 21, 2011 3:21 PM
              To: softrock40@yahoogroups.com
              Subject: Re: [softrock40] Re: Switching power supplies

               

               

              The answer varies all over the place, some are very quiet some are horrible, and some are in-between.

              I own several Samlex 25A power supplies out of 5 one was noisy, the others were pretty quiet, so I took all 5 apart and the wires heading for the output connectors were wound around a large Ferrite core with multiple size capacitors to ground (.001uF, .01uF, and .1uF of good quality) all five are quiet as a church mouse.

              On the other hand my Dell laptop when running on batteries can be heard all over the spectrum, while plugged in it's not too bad.

              At 04:49 PM 10/21/2011, you wrote:

              I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum.
              I've found one switching PS 12V/2A that is quiet above 10MHz. Using it with my FT-817.

              As for RX Softrocks, the smallest linear wall warts (100-150mA) seem to give the best results. They are also usually free or 25c at garage sales.
              The RX lineup has a 7805 regulator, so the supply doesn't have to be regulated.

              73, Mike

              --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
              >
              > This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter? 
              >
              >
              >
              > Preston WJ2V
              >

              Cecil
              k5nwa
              http://www.softrockradio.org/ > <  http://thepartsplace.k5nwa.com/ >
              http://parts.softrockradio.org/ >

              Never take life seriously. Nobody gets out alive anyway.

            • DUANE BAADE
              Preston, All of the power supplies that I use for my Flex 5000A, Flex 1500, and HPSDR are switching power supplies, and I have no problems with them at all. I
              Message 6 of 11 , Oct 21, 2011
              • 0 Attachment
                Preston,

                All of the power supplies that I use for my Flex 5000A, Flex 1500, and HPSDR are switching power supplies, and I have no problems with them at all. I also have an ALS 600 with the switching power supply, and I see no problem with it either. I am using the Astron SS-30M power supplies. The meters on mine are not illuminated, but I have read that the ones from Astron with the illuminated meters are noisy. The problem supposedly is the power that they are using for illumination. In my experience, the newer switchers seem to be pretty clean. I hope you have good luck if you get a switcher, their weight is really nice compared to the old transformer power supplies.

                Duane    W5PNM


                From: Preston Douglas <pdouglas12@...>
                To: softrock40@yahoogroups.com
                Sent: Friday, October 21, 2011 3:08 PM
                Subject: [softrock40] Switching power supplies



                This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter?  


                Preston WJ2V




              • Preston Douglas
                Thanks, Cecil. What size/spec toroid did you use, for future reference? I suspect that the MFJ 25 Amp P/S is a Samlex in disguise, or similar. It was
                Message 7 of 11 , Oct 22, 2011
                • 0 Attachment
                  Thanks, Cecil.  What size/spec toroid did you use, for future reference?  

                  I suspect that the MFJ 25 Amp P/S  is a Samlex in disguise, or similar.  It was reviewed in QST favorably.  I think I'll give it a try.
                  Thanks.


                  Preston WJ2V

                  -----Original Message-----
                  From: cbayona <CBayona@...>
                  To: softrock40 <softrock40@yahoogroups.com>
                  Sent: Fri, Oct 21, 2011 2:21 pm
                  Subject: Re: [softrock40] Re: Switching power supplies

                   
                  The answer varies all over the place, some are very quiet some are horrible, and some are in-between.

                  I own several Samlex 25A power supplies out of 5 one was noisy, the others were pretty quiet, so I took all 5 apart and the wires heading for the output connectors were wound around a large Ferrite core with multiple size capacitors to ground (.001uF, .01uF, and .1uF of good quality) all five are quiet as a church mouse.

                  On the other hand my Dell laptop when running on batteries can be heard all over the spectrum, while plugged in it's not too bad.

                  At 04:49 PM 10/21/2011, you wrote:
                  I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum.
                  I've found one switching PS 12V/2A that is quiet above 10MHz. Using it with my FT-817.

                  As for RX Softrocks, the smallest linear wall warts (100-150mA) seem to give the best results. They are also usually free or 25c at garage sales.
                  The RX lineup has a 7805 regulator, so the supply doesn't have to be regulated.

                  73, Mike

                  --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
                  >
                  > This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter? 
                  >
                  >
                  >
                  > Preston WJ2V
                  >
                  Cecil
                  k5nwa
                  http://www.softrockradio.org/ > <  http://thepartsplace.k5nwa.com/ >
                  http://parts.softrockradio.org/ >

                  Never take life seriously. Nobody gets out alive anyway.
                • cbayona
                  It s hard to say, these were surplus snap on cores made for noise suppression that I bought several years ago. These power supplies were bought from Radio
                  Message 8 of 11 , Oct 22, 2011
                  • 0 Attachment
                    It's hard to say, these were surplus snap on cores made for noise suppression that I bought several years ago.

                    These power supplies were bought from Radio Shack when they were being discontinued a few years ago, I bought them for $19, quite a bargain. I heard on another list that they were Samlex power supplies which have a good reputation, when I open the cases it was so, I've had no problems with them.

                    MFJ is a manufacturer so I would doubt they are made by someone else unless you know someone that has opened one up.

                    At 10:18 AM 10/22/2011, you wrote:


                    Thanks, Cecil.  What size/spec toroid did you use, for future reference?  

                    I suspect that the MFJ 25 Amp P/S  is a Samlex in disguise, or similar.  It was reviewed in QST favorably.  I think I'll give it a try.
                    Thanks.


                    Preston WJ2V

                    -----Original Message-----
                    From: cbayona <CBayona@...>
                    To: softrock40 <softrock40@yahoogroups.com>
                    Sent: Fri, Oct 21, 2011 2:21 pm
                    Subject: Re: [softrock40] Re: Switching power supplies

                     
                    The answer varies all over the place, some are very quiet some are horrible, and some are in-between.

                    I own several Samlex 25A power supplies out of 5 one was noisy, the others were pretty quiet, so I took all 5 apart and the wires heading for the output connectors were wound around a large Ferrite core with multiple size capacitors to ground (.001uF, .01uF, and .1uF of good quality) all five are quiet as a church mouse.

                    On the other hand my Dell laptop when running on batteries can be heard all over the spectrum, while plugged in it's not too bad.

                    At 04:49 PM 10/21/2011, you wrote:
                    I tried a couple of switching supplies with Ensemble RX II and Ensemble VHF, both from old cellphones. The hash was terrible across the spectrum.
                    I've found one switching PS 12V/2A that is quiet above 10MHz. Using it with my FT-817.

                    As for RX Softrocks, the smallest linear wall warts (100-150mA) seem to give the best results. They are also usually free or 25c at garage sales.
                    The RX lineup has a 7805 regulator, so the supply doesn't have to be regulated.

                    73, Mike

                    --- In softrock40@yahoogroups.com , Preston Douglas <pdouglas12@...> wrote:
                    >
                    > This is a general question about SDR rigs and switching power supplies.  One of my linear 12v supplies was drowned in a basement flood thanks to  hurricane Irene.  I am thinking of replacing it with a small switching supply from MFJ, particularly since it can sit on the operating desk without stressing it with the weight of an equivalent linear supply.  One of the reasons I lost the linear supply was that it was mounted on a shelf near the floor, so the water reached it.  It would be safer up on the desk.  So, are any of you using a switching supply with an SDR rig (Softrock, Flex, etc.) and if so, are you getting a lot of hash on the panadapter? 
                    >
                    >
                    >
                    > Preston WJ2V
                    >
                    Cecil
                    k5nwa
                    http://www.softrockradio.org/ > <  http://thepartsplace.k5nwa.com/ >
                    http://parts.softrockradio.org/ >

                    Never take life seriously. Nobody gets out alive anyway.

                    Cecil
                    k5nwa
                    http://www.softrockradio.org/ > <  http://thepartsplace.k5nwa.com/ >
                    http://parts.softrockradio.org/ >

                    Never take life seriously. Nobody gets out alive anyway.

                  • jeffthom99
                    ... I have that MFJ 25Amp switching supply in play with my FT-450. On first connecting the rig together I heard awful noise, like switching supply hash. Hmmm
                    Message 9 of 11 , Oct 26, 2011
                    • 0 Attachment
                      --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
                      >
                      > Thanks, Cecil. What size/spec toroid did you use, for future reference?
                      >
                      >
                      > I suspect that the MFJ 25 Amp P/S is a Samlex in disguise, or similar. It was reviewed in QST favorably. I think I'll give it a try.
                      > Thanks.
                      >
                      >
                      >
                      >
                      >
                      > Preston WJ2V
                      >

                      I have that MFJ 25Amp switching supply in play with my FT-450. On first connecting the rig together I heard awful noise, like switching supply hash. Hmmm - took the 12V battery out of my Harley, hooked it up and got the same thing. Turned out to be a bad motor control circuit on a nearby (75 ft.( 25m)) sewer lift pump. Crappy filtering! :)

                      I took the whole lot to a friend's shack across town and I could not tell whether the battery or the switching supply was powering the rig!

                      This power supply goes on sale at AES here in the Orlando area about twice a year for just under a hundred bucks. Excellent value for money, I'd say!

                      72

                      Jeff, W3HVU/4
                    • Preston Douglas
                      Thanks for the info. Very helpful. PJD ... From: jeffthom99 To: softrock40 Sent: Wed, Oct 26, 2011 10:38 am
                      Message 10 of 11 , Oct 26, 2011
                      • 0 Attachment
                        Thanks for the info.  Very helpful.

                        PJD




                        -----Original Message-----
                        From: jeffthom99 <jeff@...>
                        To: softrock40 <softrock40@yahoogroups.com>
                        Sent: Wed, Oct 26, 2011 10:38 am
                        Subject: [softrock40] Re: Switching power supplies

                         


                        --- In softrock40@yahoogroups.com, Preston Douglas <pdouglas12@...> wrote:
                        >
                        > Thanks, Cecil. What size/spec toroid did you use, for future reference?
                        >
                        >
                        > I suspect that the MFJ 25 Amp P/S is a Samlex in disguise, or similar. It was reviewed in QST favorably. I think I'll give it a try.
                        > Thanks.
                        >
                        >
                        >
                        >
                        >
                        > Preston WJ2V
                        >

                        I have that MFJ 25Amp switching supply in play with my FT-450. On first connecting the rig together I heard awful noise, like switching supply hash. Hmmm - took the 12V battery out of my Harley, hooked it up and got the same thing. Turned out to be a bad motor control circuit on a nearby (75 ft.( 25m)) sewer lift pump. Crappy filtering! :)

                        I took the whole lot to a friend's shack across town and I could not tell whether the battery or the switching supply was powering the rig!

                        This power supply goes on sale at AES here in the Orlando area about twice a year for just under a hundred bucks. Excellent value for money, I'd say!

                        72

                        Jeff, W3HVU/4

                      • Dave
                        Take care trying to use old cellphone wall-wart s as PSU s . Many are not PSU s as such, but Chargers. As such, they do not regulate well (if at all) with a
                        Message 11 of 11 , Nov 2, 2011
                        • 0 Attachment
                          Take care trying to use old cellphone wall-wart's as "PSU's".

                          Many are not PSU's as such, but Chargers. As such, they do not regulate
                          well (if at all) with a very light load, such as an SDR.

                          Also, those that do regulate, might do so, in a way that changes the
                          "mode" of operation of the Switcher itself, from Continuious to
                          Discontinuious mode, dramaticaly altering it's RFI spectrum, making any
                          filtering it has less effective than it might be in "normal" use..

                          Joking apart, sometimes adding extra load to some small (and large)
                          SMPS's, can help keep them quiet(er) than they would otherwise be.

                          Go for about 30% or more of their nominal rated output. Check on the
                          ratings plate, label, embossing, for what they are rated to provide, some
                          are suprisingly powerfull, but most are not easy to read that data from.

                          73.

                          Dave G0WBX.
                        Your message has been successfully submitted and would be delivered to recipients shortly.