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Re: [loopantennas] RE: Homebrew LZ1AQ amplifier

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  • everettsharp74
    Hi Cor, I have not seen any of Chris s writings below, however, Steve Ratzlaff, is the one that filled me in on changing the coils to connect directly to the
    Message 1 of 26 , Oct 7, 2013
      Hi Cor,
       
      I have not seen any of Chris's writings below, however, Steve Ratzlaff, is the one that filled me in on changing the coils to connect directly to the Collectors on Q1 and Q2, I found out through experimenting that the amp worked better using 1 uF cap, rather then the .01 uF that it called for between the amp and the loop.
       
      Yesterday I made another change to the amp by removing the two 100 ohm resisters feeding the two coils and changed transistors. Now it works even better yet. It is now drawing 55 ma @ 8.25 V, whereas it was only drawing about 35 ma at the same voltage. I also changed the transistors to MPSH-10, thus replacing the 2N2222's. (Note: if you are considering using the MPSH-10 transistors, the pin outs are different than the 2N2222, rather than E, B, C, they are B, E, C, I found out the hard way)
       
      I tried it on the Mobius and it worked okay, but I was not able to get the 30 dB nulls, so I tried a 1:1, 1:2 and a 1:3 matching transformer and with the 1:3  I was able to get the 30 dB nulls. Also I noticed that it worked much better up band on 10 meters. Today I will compare it to the Clifton Z10046A amplifier.
       
      I am happy with the mobius loop, using the PEX AL PEX pipe, as I am able to get deeper nulls with it than a conventional shielded loop. Also it is way better than a 1 meter wire loop, as it has a lot less noise and you are able to null out most noise with the mobius. For the mobius to work well you need to get the capacitance down and you just can not do it with off the shelf coax. If you don't have, or can't get the PEX AL PEX pipe, then you could make up a coax loop like I did in the article. However, you need to have the loop capacitance down to 150 pF, or below, if you want the 30 dB nulls. It still works well above that, but you will not get the 30 dB nulls. I was only able to get 25 dB nulls with the home made coax loop, but other than that it worked as well as the PEX AL PEX mobius.
       
      Everett
       
       
       
      In a message dated 10/7/2013 2:41:01 A.M. Central Daylight Time, dx11@... writes:
       

      Hello Everett,

      Three years ago the M0AYF antenna was also discussed in this group, Chris Trask gave the following contribution to the discussion (2010, July 20):

      “One item I find missing from this design is an input BalBal transformer.  Such a transformer would serve a number of uses, in particular providing a degree of immunity from common-mode interference such as lightning strikes.  It would also provide a ground reference for the antenna proper, and in addition would allow the two transistors to have an identical base voltage.  The limiting diodes would be placed across the primary side of the transformer. 

           I would also disconnect the two emitters, have a separate biasing resistor from each emitter to ground, and then a suitable capacitor between the two emitters.  Then the two capacitors from the collectors to the output transformer primary winding can be eliminated.  The 1:1 UnUn output transformer could be replaced with a 1:1:1 BalUn, the centre tap of the primary connected to the supply line.  This would increase the P1dB a bit plus raise the gain by an additional 6dB.”

      I built the original circuit, but I’m planning a further one along Chris’ recommendations.

      In your document about your experiments with Moebius loops you were not very positive about the M0AYF design. Later on after changing to a different amplifier you found a large improvement by connecting the loop coax braid to the amplifier ground. Did you try that with the M0AYF as well. What made you change your opinion on the M0AYF?

      Cor Beijersbergen

      From: loopantennas@yahoogroups.com [mailto:loopantennas@yahoogroups.com] On Behalf Of everettsharp@...
      Sent: zondag 6 oktober 2013 18:12
      To: loopantennas@yahoogroups.com
      Subject: Re: [loopantennas] RE: Homebrew LZ1AQ amplifier

      Guys,

      I found that this modified M0AYF amp works much better than the IZ1AG amp.

      Everett N8CNP

      In a message dated 10/4/2013 8:17:53 A.M. Central Daylight Time, syomin@... writes:

       

      > Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. 

      Not principal, as for me.

      > Does the inclusion of protection diodes effect the low-pass filter much?

      Don't know. I just guided by this article:

      http://lz1aq.signacor.com/docs/Wide_Mag_loop_prot_v1/wideband_mag_loop_protection.htm



      ---In loopantennas@yahoogroups.com, <crusty@...> wrote:

      Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. Does the inclusion of protection diodes effect the low-pass filter much? 



      ---In loopantennas@yahoogroups.com, <syomin@...> wrote:

      Hi , everybody!<div><br></div><div>I have designed PCB to build my own LZ1AQ amplifier at home. I want to share CAD project with comunity - to open it you need to download and install DipTrace program (<a rel="nofollow" target="_blank" href="http://www.diptrace.com/?en=1" style="line-height:1.22;">

    • Jim
      Not sure if Chris is on this group. If so, Chris, did you physically build a unit and perform tests or was this done using simulation or based on experince?
      Message 2 of 26 , Oct 7, 2013
        
        Not sure if Chris is on this group.
         
        If so, Chris, did you physically build a unit and perform tests or was this done using simulation or based on experince?
         
        Tnx
         
        Jim
        ----- Original Message -----
        From: dx11
        Sent: Monday, October 07, 2013 12:40 AM
        Subject: RE: [loopantennas] RE: Homebrew LZ1AQ amplifier

         

        Hello Everett,

        Three years ago the M0AYF antenna was also discussed in this group, Chris Trask gave the following contribution to the discussion (2010, July 20):

        “One item I find missing from this design is an input BalBal transformer.  Such a transformer would serve a number of uses, in particular providing a degree of immunity from common-mode interference such as lightning strikes.  It would also provide a ground reference for the antenna proper, and in addition would allow the two transistors to have an identical base voltage.  The limiting diodes would be placed across the primary side of the transformer. 

             I would also disconnect the two emitters, have a separate biasing resistor from each emitter to ground, and then a suitable capacitor between the two emitters.  Then the two capacitors from the collectors to the output transformer primary winding can be eliminated.  The 1:1 UnUn output transformer could be replaced with a 1:1:1 BalUn, the centre tap of the primary connected to the supply line.  This would increase the P1dB a bit plus raise the gain by an additional 6dB.”

        I built the original circuit, but I’m planning a further one along Chris’ recommendations.

        In your document about your experiments with Moebius loops you were not very positive about the M0AYF design. Later on after changing to a different amplifier you found a large improvement by connecting the loop coax braid to the amplifier ground. Did you try that with the M0AYF as well. What made you change your opinion on the M0AYF?

        Cor Beijersbergen

        From: loopantennas@yahoogroups.com [mailto:loopantennas@yahoogroups.com] On Behalf Of everettsharp@...
        Sent: zondag 6 oktober 2013 18:12
        To: loopantennas@yahoogroups.com
        Subject: Re: [loopantennas] RE: Homebrew LZ1AQ amplifier

        Guys,

        I found that this modified M0AYF amp works much better than the IZ1AG amp.

        Everett N8CNP

        In a message dated 10/4/2013 8:17:53 A.M. Central Daylight Time, syomin@... writes:

         

        > Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. 

        Not principal, as for me.

        > Does the inclusion of protection diodes effect the low-pass filter much?

        Don't know. I just guided by this article:

        http://lz1aq.signacor.com/docs/Wide_Mag_loop_prot_v1/wideband_mag_loop_protection.htm



        ---In loopantennas@yahoogroups.com, <crusty@...> wrote:

        Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. Does the inclusion of protection diodes effect the low-pass filter much? 



        ---In loopantennas@yahoogroups.com, <syomin@...> wrote:

        Hi , everybody!<div><br></div><div>I have designed PCB to build my own LZ1AQ amplifier at home. I want to share CAD project with comunity - to open it you need to download and install DipTrace program (<a rel="nofollow" target="_blank" href="http://www.diptrace.com/?en=1" style="line-height:1.22;">

      • pond.james_pond
        I built and modified the M0AYF amp for better Imd performance, and used it for some time. I ve also built 2 of Chris s, 2 Nortons, the LZ1AQ and some
        Message 3 of 26 , Oct 7, 2013

          I built and modified the M0AYF amp for better Imd performance, and used it for some time. I've also built 2 of Chris's, 2 Nortons, the LZ1AQ and some (mediocre) attempts of my own. The stock LZ1AQ design built ugly style, with a single fat 80cm diameter copper loop has for me, been the most consistent performer for general HF listening. I think much depends on requirements and operating conditions. My main problem is strong local noise, something the M0AFY didn't handle well even when modified, or with a shielded loop.


          I hope this gets to the list, for me using the web interface Yahoo groups are broken, almost impossible to follow post threads.

          73.



          ---In loopantennas@yahoogroups.com, <everettsharp@...> wrote:

          Guys,
           
          I found that this modified M0AYF amp works much better than the IZ1AG amp.
           
           
          Everett N8CNP
           
          In a message dated 10/4/2013 8:17:53 A.M. Central Daylight Time, syomin@... writes:
           

          > Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. 

          Not principal, as for me.


          > Does the inclusion of protection diodes effect the low-pass filter much?

          Don't know. I just guided by this article:

          http://lz1aq.signacor.com/docs/Wide_Mag_loop_prot_v1/wideband_mag_loop_protection.htm



          ---In loopantennas@yahoogroups.com, <crusty@...> wrote:

          Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. Does the inclusion of protection diodes effect the low-pass filter much? 



          ---In loopantennas@yahoogroups.com, <syomin@...> wrote:

          Hi , everybody!<div><br></div><div>I have designed PCB to build my own LZ1AQ amplifier at home. I want to share CAD project with comunity - to open it you need to download and install DipTrace program (<a rel="nofollow" target="_blank" href="http://www.diptrace.com/?en=1" style="line-height:1.22;">
        • Chris Trask
          ... Yes, I m here. I ve been watching this thread waiting for an appropriate opportunity to make a comment or two. ... Based on both, actually. I use it as
          Message 4 of 26 , Oct 7, 2013
            >
            >Not sure if Chris is on this group.
            >

            Yes, I'm here. I've been watching this thread waiting for an appropriate opportunity to make a comment or two.

            >
            >If so, Chris, did you physically build a unit and perform tests or was this done using simulation or
            >based on experince?
            >

            Based on both, actually. I use it as standard design practice to avoid common-mode distortion at every stage whenever practical.


            Chris
          • watlingm
            ... it might work even better if you replace R8 with a ground gate JFET like J310 or J309 otherwise looks pretty good, I note R4 and R5 has double duty as part
            Message 5 of 26 , Oct 8, 2013

               



              ---In loopantennas@yahoogroups.com, <loopantennas@yahoogroups.com> wrote:

              it might work even better if you replace R8 with a ground gate JFET like J310 or J309

              otherwise looks pretty good, I note R4 and R5 has double duty as part of base bias and negative feedback

              best Paul


              From: "everettsharp@..." <everettsharp@...>
              To: loopantennas@yahoogroups.com
              Sent: Sunday, October 6, 2013 12:11:57 PM
              Subject: Re: [loopantennas] RE: Homebrew LZ1AQ amplifier

              Guys,
               
              I found that this modified M0AYF amp works much better than the IZ1AG amp.
               
               
              Everett N8CNP
               
              In a message dated 10/4/2013 8:17:53 A.M. Central Daylight Time, syomin@... writes:
               
              > Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. 
              Not principal, as for me.

              > Does the inclusion of protection diodes effect the low-pass filter much?
              Don't know. I just guided by this article:


              ---In loopantennas@yahoogroups.com, <crusty@...> wrote:

              Thank you. I noticed the power regulation filtering/decoupling differs from the original schematic. Does the inclusion of protection diodes effect the low-pass filter much? 


              ---In loopantennas@yahoogroups.com, <syomin@...> wrote:

              Hi , everybody!<div><br></div><div>I have designed PCB to build my own LZ1AQ amplifier at home. I want to share CAD project with comunity - to open it you need to download and install DipTrace program (<a rel="nofollow" target="_blank" href="http://www.diptrace.com/?en=1" style="line-height:1.22;">


            • Steinar Aanesland
              Hi all, This is my first writing to the group, but I have been lurking around for awhile. Does any of you guys know this product?
              Message 6 of 26 , Oct 11, 2013
                Hi all,

                This is my first writing to the group, but I have been lurking around
                for awhile.
                Does any of you guys know this product?

                http://inac-radio.com/en/Condensador-variable-de-30700-Hidroil

                LA5VNA Steinar
              • Steinar Aanesland
                Hi all, This is my first writing to the group, but I have been lurking around for awhile. Does any of you guys know this product?
                Message 7 of 26 , Oct 11, 2013
                  Hi all,

                  This is my first writing to the group, but I have been lurking around
                  for awhile.
                  Does any of you guys know this product?
                  http://inac-radio.com/en/Condensador-variable-de-30700-Hidroil

                  LA5VNA Steinar
                • Steinar Aanesland
                  OK, probably not :) LA5VNA S
                  Message 8 of 26 , Oct 12, 2013
                    OK, probably not :)

                    LA5VNA S





                    On 11.10.2013 13:54, Steinar Aanesland wrote:
                    > Hi all,
                    >
                    > This is my first writing to the group, but I have been lurking around
                    > for awhile.
                    > Does any of you guys know this product?
                    > http://inac-radio.com/en/Condensador-variable-de-30700-Hidroil
                    >
                    > LA5VNA Steinar
                    >
                    >
                    >
                    >
                    >
                    > ------------------------------------
                    >
                    > If you've got links, post them in the Links section!
                    > http://groups.yahoo.com/group/loopantennas/links
                    >
                    > Post files here. If the file comes from a website, please put it in the Links rather than uploading the file.
                    > http://groups.yahoo.com/group/loopantennas/files
                    >
                    > You can now view images at higher resolution in Photos. Upload JPG and GIF into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
                    > http://ph.groups.yahoo.com/group/loopantennas/photos
                    >
                    > And please trim all this when replying!Yahoo! Groups Links
                    >
                    >
                    >
                    >
                    >
                  • roberts50000
                    Hi Steinar, When I tried to read about the Hidroil capacitor I could never download the full page. For some reason my browser would lock up when trying to
                    Message 9 of 26 , Oct 13, 2013
                      Hi Steinar,
                      When I tried to read about the Hidroil capacitor I could never download
                      the full page. For some reason my browser would lock up when trying
                      to download the full page. Sorry to say I cannot read the language
                      either.

                      Could you describe to us what the Hidroil capacitor is? It looks like
                      someone put together an interesting high-power capacitor for a
                      transmitting loop antenna with some kind of built-in motorized
                      tuning and remote control? It looks like nice wide copper tabs to
                      make connections to the loop.

                      Is the capacitor immersed in some kind of oil? What does the
                      30/700 number stand for? Thanks for any additional info.

                      73 - Todd WD4NGG


                      In a message dated 10/13/2013 11:14:49 A.M. Eastern Daylight Time,
                      saanes@... writes:

                      OK, probably not :)

                      LA5VNA S

                      On 11.10.2013 13:54, Steinar Aanesland wrote:
                      > Hi all,
                      >
                      > This is my first writing to the group, but I have been lurking around
                      > for awhile.
                      > Does any of you guys know this product?
                      > http://inac-radio.com/en/Condensador-variable-de-30700-Hidroil
                      >
                      > LA5VNA Steinar
                    • redsp
                      I did a little searching and found this page. Looks like you were spot on!
                      Message 10 of 26 , Oct 13, 2013
                        I did a little searching and found this page.  Looks like you were spot on! 


                        For those who can't even see the above link..

                        http://tinyurl.com/hidroil-cap

                        It seems to be another page from the same vendor but with a different illustration.  

                        Here is the description...

                        "Variable capacitor, with servomotor. 20/330pF 7.5 Kvols.
                        In airtight ABS. Condenser motor and immersed in a dielectric HIDROIL.
                        With tubing connection 28mm bronze. You can request other connection.
                        Condenser for conducting a large loop antenna performance."

                        7.5 kV!  I guess that is for a rather high power transmitter. 

                        Rick
                      • Steinar Aanesland
                        Hi Todd, I am sorry for not responding earlier. I have had a lot of work to do lately. Yes , I think it is a motorized tuning and remote control for a
                        Message 11 of 26 , Oct 16, 2013
                          Hi Todd,

                          I am sorry for not responding earlier. I have had a lot of work to do
                          lately.

                          Yes , I think it is a motorized tuning and remote control for a capacitor .

                          I can not read the language, but I am using Google translator.

                          I was doing a Google search and came across this page (translated from
                          French to English):

                          http://translate.google.no/translate?hl=no&sl=fr&tl=en&u=http%3A%2F%2Fj28ro.blogspot.no%2F2013%2F05%2Finac-ah-521-antenne-loop-magnetique.html

                          The antenna is us using the capacitor, and the system seems interesting.

                          LA5VNA Steinar






                          On 13.10.2013 19:58, toddroberts2001@... wrote:
                          > Hi Steinar,
                          > When I tried to read about the Hidroil capacitor I could never download
                          > the full page. For some reason my browser would lock up when trying
                          > to download the full page. Sorry to say I cannot read the language
                          > either.
                          >
                          > Could you describe to us what the Hidroil capacitor is? It looks like
                          > someone put together an interesting high-power capacitor for a
                          > transmitting loop antenna with some kind of built-in motorized
                          > tuning and remote control? It looks like nice wide copper tabs to
                          > make connections to the loop.
                          >
                          > Is the capacitor immersed in some kind of oil? What does the
                          > 30/700 number stand for? Thanks for any additional info.
                          >
                          > 73 - Todd WD4NGG
                          >
                          >
                          > In a message dated 10/13/2013 11:14:49 A.M. Eastern Daylight Time,
                          > saanes@... writes:
                          >
                          > OK, probably not :)
                          >
                          > LA5VNA S
                          >
                          > On 11.10.2013 13:54, Steinar Aanesland wrote:
                          >> Hi all,
                          >>
                          >> This is my first writing to the group, but I have been lurking around
                          >> for awhile.
                          >> Does any of you guys know this product?
                          >> http://inac-radio.com/en/Condensador-variable-de-30700-Hidroil
                          >>
                          >> LA5VNA Steinar
                          >
                          >
                          >
                          > ------------------------------------
                          >
                          > If you've got links, post them in the Links section!
                          > http://groups.yahoo.com/group/loopantennas/links
                          >
                          > Post files here. If the file comes from a website, please put it in the Links rather than uploading the file.
                          > http://groups.yahoo.com/group/loopantennas/files
                          >
                          > You can now view images at higher resolution in Photos. Upload JPG and GIF into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
                          > http://ph.groups.yahoo.com/group/loopantennas/photos
                          >
                          > And please trim all this when replying!Yahoo! Groups Links
                          >
                          >
                          >
                          >
                          >
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