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Re: to balun or not to balun

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  • Paul Shinn
    For receivers, I believe the main advantage of adding a balun (not just some coiled coax) is the static drain to ground. Without the balun, the wire antenna
    Message 1 of 15 , Feb 1, 2007
      For receivers, I believe the main advantage of adding a balun (not
      just some coiled coax) is the static drain to ground. Without the
      balun, the wire antenna connects to the center of your coax (and
      directly to your receiver) and the ground to the shield. With the
      balun, there is a direct DC path from the antenna wire to ground.
      THAT is probably most responsible for the drastic reduction of noise
      in the receiver.


      --- In RADIOSHACKDX394@yahoogroups.com, "Tom Holden"
      <holden_family@...> wrote:
      >
      > I'm doubtful that a balun is going to work any miracles with an
      attic antenna in terms of improving the signal-noise ratio. Its
      impedance transforming properties are really secondary for receiving
      antennas - as you (uk_drac) noted, switching between the Hi-Z and Lo-
      Z inputs made a signficant difference in the strengths of both
      desired signal (s) and unwanted noise and interference (n+i) but not
      to their ratios, s/(n+i).
      >
      > Some of the unwanted noise and interference is generated by
      household and external electrical devices and is propagated over
      household and external wiring. We want our antenna to favour the
      desired signals and discriminate against these local sources. The
      best and general solution is to locate the antenna elements as far
      away from these sources as possible and in the clear without
      obstruction toward the desired signal, setting aside design
      specifics that address discrimination against atmospheric noise and
      remote sources of interference.
      >
      > The receiver, unfortunately, is usually sitting in the heart of
      the local morass of noise and interference. What we don't want is
      for the transmission line from the carefully located antenna to
      pickup more of this QRM and thus degrade the s/(n+i) en route to the
      radio. This is why shielded cable is used, the most common of which
      for HF use being co-axial, which is inherently unbalanced ("un"
      in "balun").
      >
      > There is also shielded, balanced cable (twin-axial) ("bal"
      in "balun"). Even unshielded, balanced transmission line (twinlead,
      ladder line, CAT5) itself can have good discrimination against
      external fields. The balanced antenna feeds the balanced line
      differentially while E-M fields crossing the transmission line
      induce equal currents (common-mode) that self-cancel in a balanced,
      differential receiver. But the DX-394 has unbalanced inputs so a
      balun would be mandatory if balanced lines are used because the
      discriminating property of so-called balanced lines degrades toward
      that of a single wire if the pair is not fed and terminated so that
      the impedance of each conductor to ground is closely matched.
      >
      > The antenna may also be balanced or unbalanced wrt ground. A
      dipole in free space is perfectly balanced. A monopole fed against
      perfectly conducting earth is perfectly unbalanced. Real antennas
      lie in between. You can see that there are 4 combinations of antenna
      and transmission line using balance as the sole criterion (bal-bal,
      unbal-unbal, bal-unbal, unbal-bal), ending up in two choices of
      unbalanced inputs on the DX-394 - Hi-Z or Lo-Z. The first two
      ant/txline combos do not require a balun between the antenna and tx
      line, while the last two do. The first and last ideally require a
      balun between the tx line and the DX-394 as well, i.e. a balun at
      both ends of the tx line.
      >
      > Real antennas are neither perfectly balanced nor unbalanced so I'm
      a little wary about going overboard with the use of transformer type
      baluns. It may be of more importance and more controllable for
      transmitting than for receiving. I've used a G5RV antenna for years,
      mainly receiving. It is a balanced dipole, fed with a specific
      length of nominally 450 ohm balanced line that connects to co-ax
      cable for the run to the antenna tuner. The co-ax shield connects to
      one side of the balanced line, the inner conductor to the other
      side. A balun is required but it is nothing more than coiling the co-
      ax at the junction end to create a choke that restricts the current
      flow on the outside of the shield arising from the bal-unbal
      mismatch. I coiled a similar choke at the entrance to the basement
      to try to restrict noise and interference currents induced on the
      outer shield from within the house from travelling along the line to
      the vicinity of the antenna. Like with Paul's longwire and 9:1
      balun, the transmission line is not behaving much like an antenna so
      the s/(n+i) is mainly determined by the antenna element.
      >
      > Your attic antenna may not be far enough away from the local n+i
      sources that you will see much benefit from discriminating against
      picking them up on the transmission line.
      > An attic antenna is a big improvement over a basement antenna but
      it is still very close to the local sources of noise and
      interference.
      >
      > For an attic antenna, I would try a mini-G5RV style dipole, using
      twinlead or speaker wire from the centre insulator down to the floor
      of the attic, connect to the co-ax, coil the co-ax there for a choke
      and again every 10' or so (if you can find the space) back to the
      radio. The choke coils can be 8-10 turns, 6" diameter (i.e., an
      extra 15' of co-ax for each choke). Route the cable so that it does
      not closely parallel other household wiring or come close to known
      sources of interference.
      >
      > You can ignore the G5RV design formula for the antenna and feeder
      lengths since impedance matching for receiving is a non-issue. Mount
      the antenna elements horizontally in a straight line (keep all bends
      less than 60 degrees total) and symmetrically with respect to the
      environment.
      >
      > Nor do we want the radio to pick up the local interference through
      its power line and ground connections or directly through its case
      into its internal circuits. Much was previously written about
      shielding of the DX-394 and maintaining good separation from strong
      EM interferors such as CRT's.
      >
      > More could be said about alternative antenna elements and
      grounding. Your attic layout may not lend itself to a straight
      dipole; maybe you have to end-feed the antenna. Whatever the case,
      use the choke principle with your co-ax transmission line to prevent
      it from carrying interference on the outside of its shield to the
      antenna and then back down inside the shield.
      >
      > 73, Tom VE3MEO
      >
      > ----- Original Message -----
      > From: Paul Shinn
      > To: RADIOSHACKDX394@yahoogroups.com
      > Sent: Sunday, January 28, 2007 11:08 AM
      > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
      >
      >
      > I have a 160 foot longwire. I experimented with various baluns.
      > Installing any balun reduced static noise (over direct coax fed)
      and
      > increased some signals. Using WWV, AM broadcast stations at the
      top
      > and bottom of the dial, and a friend 30 miles away keying up on
      the
      > various ham bands, I found that most bands had increased signal
      > strength when the balun was installed. The best signals came
      with the
      > 9:1 balun installed.
      >
      > After I returned the baluns to my friend, I ordered a 9:1 from
      DX
      > Engineering and installed it permanently. My noise is almost
      always
      > near zero and signals are strong!
      >
      > --- In RADIOSHACKDX394@yahoogroups.com, "uk_drac" <ukdrac@>
      wrote:
      > >
      > > As per usual with the net there are very convincing arguments
      out
      > for
      > > both using and not using a balun . im using a 50+ metre long
      wire
      > > circled around my attic space at the moment (not ideal i know
      but
      > > funcional), Yes i get a certain amount of skip on certain
      > frequencies
      > > if i connect it to hi-z input i get exactly the same amount
      > of "mess"
      > > coming through as i do when i use the lo-z input the only
      > difference
      > > is signal strenght. so if i use a balun or matcher unit will i
      still
      > > get the same amount of noise and interference or should i be
      able to
      > > illliminate it without signakl strengh loss?
      > >
      >
      >
      >
      >
      >
      > [Non-text portions of this message have been removed]
      >
    • Another Old Codger
      It s not the DC path that it helps, that is already covered by static discharge resistors fitted on all antenna inputs, the balun compensates for the unbalance
      Message 2 of 15 , Feb 1, 2007
        It's not the DC path that it helps, that is already covered by static
        discharge resistors fitted on all antenna inputs, the balun
        compensates for the unbalance of the coax feeder and prevents current
        travelling on the screen of the feeder.

        Any good antenna book will give a full explanation.

        As far as the static discharge resistors are concerned they are
        mandatory in most countries to prevent the build up of dangerous
        static on the feeder.

        One of the amazing things about Ham Radio is the vast quantity of
        excellent books available covering every aspect of the Hobby, and
        compared with the price of most Ham gear the books are a low cost.

        Ron.
        ----- Original Message -----
        From: "Paul Shinn" <subscriptions@...>
        To: <RADIOSHACKDX394@yahoogroups.com>
        Sent: Thursday, February 01, 2007 3:47 PM
        Subject: [RADIOSHACKDX394] Re: to balun or not to balun


        For receivers, I believe the main advantage of adding a balun (not
        just some coiled coax) is the static drain to ground. Without the
        balun, the wire antenna connects to the center of your coax (and
        directly to your receiver) and the ground to the shield. With the
        balun, there is a direct DC path from the antenna wire to ground.
        THAT is probably most responsible for the drastic reduction of noise
        in the receiver.
      • Tom Holden
        I was just about to say the same thing having just checked the DX-394 schematic when I read your post. The DX-394 has a 1K drain across the Lo-Z and a 100K
        Message 3 of 15 , Feb 1, 2007
          I was just about to say the same thing having just checked the DX-394 schematic when I read your post. The DX-394 has a 1K drain across the Lo-Z and a 100K across the Hi-Z.

          73, Tom VE3MEO

          ----- Original Message -----
          From: Another Old Codger
          To: RADIOSHACKDX394@yahoogroups.com
          Sent: Thursday, February 01, 2007 12:44 PM
          Subject: Re: [RADIOSHACKDX394] Re: to balun or not to balun


          It's not the DC path that it helps, that is already covered by static
          discharge resistors fitted on all antenna inputs, the balun
          compensates for the unbalance of the coax feeder and prevents current
          travelling on the screen of the feeder.


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          [Non-text portions of this message have been removed]
        • Paul Shinn
          A 1K resistor in the radio is not as good of a drain as a 0 ohm (at DC) path at the feedpoint. ... static ... current ... noise
          Message 4 of 15 , Feb 3, 2007
            A 1K resistor in the radio is not as good of a drain as a 0 ohm (at
            DC) path at the feedpoint.


            --- In RADIOSHACKDX394@yahoogroups.com, "Another Old Codger"
            <clattering.ford@...> wrote:
            >
            > It's not the DC path that it helps, that is already covered by
            static
            > discharge resistors fitted on all antenna inputs, the balun
            > compensates for the unbalance of the coax feeder and prevents
            current
            > travelling on the screen of the feeder.
            >
            > Any good antenna book will give a full explanation.
            >
            > As far as the static discharge resistors are concerned they are
            > mandatory in most countries to prevent the build up of dangerous
            > static on the feeder.
            >
            > One of the amazing things about Ham Radio is the vast quantity of
            > excellent books available covering every aspect of the Hobby, and
            > compared with the price of most Ham gear the books are a low cost.
            >
            > Ron.
            > ----- Original Message -----
            > From: "Paul Shinn" <subscriptions@...>
            > To: <RADIOSHACKDX394@yahoogroups.com>
            > Sent: Thursday, February 01, 2007 3:47 PM
            > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
            >
            >
            > For receivers, I believe the main advantage of adding a balun (not
            > just some coiled coax) is the static drain to ground. Without the
            > balun, the wire antenna connects to the center of your coax (and
            > directly to your receiver) and the ground to the shield. With the
            > balun, there is a direct DC path from the antenna wire to ground.
            > THAT is probably most responsible for the drastic reduction of
            noise
            > in the receiver.
            >
          • Wm Barrett
            Call me silly, but for decades I ve put a 100k resistor at the dipole s feedpoint. I use a center insulator made up of PVC pipe which seals the feedpoint off
            Message 5 of 15 , Feb 3, 2007
              Call me silly, but for decades I've put a 100k resistor at the dipole's
              feedpoint. I use a center insulator made up of PVC pipe which seals
              the feedpoint off from weather. I've never botthered with baluns.

              http://www.StudioOne-CT.com/Images/Dipole.gif

              I know many folks swear by them, but I've found that if the antenna
              is cut right, and if I let about ten or twenty feet of coax lie on the
              ground as it runs into my basement window, baluns seem to make
              zero difference in real-world on-the-air performance. That I can
              observe, anyway.

              My dipoles are usually somewhat "NVIS-y" about 1/4 wave off the
              earth or even a bit less for the 80 meter job. The way the property
              here is structured, there is a narrow woodsy part circling the open
              lawn-y part in the center where the house is. So, coax dropping
              down into the woods, and running across the 10 0r 20 feet of grass
              between is simply easy.

              My working theory is that the section of coax laying in the grass
              is a lossy choke for any RF flowing on the outside of the coax.

              Dunno, but it seems to work. It's useful lightning protection, too.
              The lightning has a lot of opportunity to jump to earth before
              reaching the window. That, and I never leave the radios connected
              to any antennas if I'm not here. I have a disconnect panel at the
              window, and I just let the coaxes drop away from the disconnect
              panel, providing about three feet of physical separation when they're
              all unplugged.

              Nothing can handle or survive a direct hit. But these kinds of
              procedures will save your gear when a nearby hit---50 yards or
              less---happens. Those kinds if hits are far more common.

              73
              W1WJB








              ----- Original Message -----
              From: "Paul Shinn" <subscriptions@...>
              To: <RADIOSHACKDX394@yahoogroups.com>
              Sent: Saturday, February 03, 2007 11:34 AM
              Subject: [RADIOSHACKDX394] Re: to balun or not to balun


              > A 1K resistor in the radio is not as good of a drain as a 0 ohm (at
              > DC) path at the feedpoint.
              >
              >
              > --- In RADIOSHACKDX394@yahoogroups.com, "Another Old Codger"
              > <clattering.ford@...> wrote:
              > >
              > > It's not the DC path that it helps, that is already covered by
              > static
              > > discharge resistors fitted on all antenna inputs, the balun
              > > compensates for the unbalance of the coax feeder and prevents
              > current
              > > travelling on the screen of the feeder.
              > >
              > > Any good antenna book will give a full explanation.
              > >
              > > As far as the static discharge resistors are concerned they are
              > > mandatory in most countries to prevent the build up of dangerous
              > > static on the feeder.
              > >
              > > One of the amazing things about Ham Radio is the vast quantity of
              > > excellent books available covering every aspect of the Hobby, and
              > > compared with the price of most Ham gear the books are a low cost.
              > >
              > > Ron.
              > > ----- Original Message -----
              > > From: "Paul Shinn" <subscriptions@...>
              > > To: <RADIOSHACKDX394@yahoogroups.com>
              > > Sent: Thursday, February 01, 2007 3:47 PM
              > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
              > >
              > >
              > > For receivers, I believe the main advantage of adding a balun (not
              > > just some coiled coax) is the static drain to ground. Without the
              > > balun, the wire antenna connects to the center of your coax (and
              > > directly to your receiver) and the ground to the shield. With the
              > > balun, there is a direct DC path from the antenna wire to ground.
              > > THAT is probably most responsible for the drastic reduction of
              > noise
              > > in the receiver.
              > >
              >
              >
              >
              >
              > Trim all but the core of this message when replying to keep replies from
              mushrooming in size.
              > For archives of prior messages, files, links, photos, user survey, members
              info, etc., visit our group on the WWW.
              > Yahoo! Groups Links
              >
              >
              >
              >
              >
              >
            • Rob Mills
              ... From: Wm Barrett To: Sent: Saturday, February 03, 2007 12:12 PM Subject: Re: [RADIOSHACKDX394]
              Message 6 of 15 , Feb 3, 2007
                ----- Original Message -----
                From: "Wm Barrett" <bill@...>
                To: <RADIOSHACKDX394@yahoogroups.com>
                Sent: Saturday, February 03, 2007 12:12 PM
                Subject: Re: [RADIOSHACKDX394] Re: to balun or not to balun


                >>> baluns seem to make zero difference in real-world on-the-air
                performance. That I can observe, anyway.<<<

                Thanks for posting, I was starting to get an inferiority complex. :)
              • Wm Barrett
                Humbug. I baluns were necessary, God would make ferrite cores grow in the garden on little decorative bushes.. ;-) 73 W1WJB ... From: Rob Mills
                Message 7 of 15 , Feb 3, 2007
                  Humbug. I baluns were necessary, God would make ferrite cores
                  grow in the garden on little decorative bushes..

                  ;-)

                  73
                  W1WJB


                  ----- Original Message -----
                  From: "Rob Mills" <robmills@...>
                  To: <RADIOSHACKDX394@yahoogroups.com>
                  Sent: Saturday, February 03, 2007 1:29 PM
                  Subject: Re: [RADIOSHACKDX394] Re: to balun or not to balun


                  >
                  > ----- Original Message -----
                  > From: "Wm Barrett" <bill@...>
                  > To: <RADIOSHACKDX394@yahoogroups.com>
                  > Sent: Saturday, February 03, 2007 12:12 PM
                  > Subject: Re: [RADIOSHACKDX394] Re: to balun or not to balun
                  >
                  >
                  > >>> baluns seem to make zero difference in real-world on-the-air
                  > performance. That I can observe, anyway.<<<
                  >
                  > Thanks for posting, I was starting to get an inferiority complex. :)
                  >
                  >
                  >
                  > Trim all but the core of this message when replying to keep replies from
                  mushrooming in size.
                  > For archives of prior messages, files, links, photos, user survey, members
                  info, etc., visit our group on the WWW.
                  > Yahoo! Groups Links
                  >
                  >
                  >
                  >
                  >
                  >
                • Paul Shinn
                  My coax from the balun to the shack runs completely under ground (about 70 feet total) and the balun still made the huge difference. Regarding disconnecting
                  Message 8 of 15 , Feb 4, 2007
                    My coax from the balun to the shack runs completely under ground
                    (about 70 feet total) and the balun still made the huge difference.

                    Regarding disconnecting coaxes, if the disconnect box is in or on
                    your house, that leaves lightning right at your doorstep. Unless
                    the disconnect is at the antenna feedpoint, you are still looking at
                    a possible problem.

                    BTW, you stated "Nothing can handle or survive a direct hit" that is
                    untrue. I have a Polyphaser right at the balun where the coax
                    connects to it, and my tower has been hit (I live on top of a
                    mountain). No radio damage at all. In fact, one of my commercial
                    sites gets hit all the time, and the radios stay on right through
                    the strike and don't even know it happened. They DO work.

                    No, I do not sell them or have any interest in the company! Just to
                    squelch that problem.


                    --- In RADIOSHACKDX394@yahoogroups.com, "Wm Barrett" <bill@...>
                    wrote:
                    >
                    > Call me silly, but for decades I've put a 100k resistor at the
                    dipole's
                    > feedpoint. I use a center insulator made up of PVC pipe which
                    seals
                    > the feedpoint off from weather. I've never botthered with baluns.
                    >
                    > http://www.StudioOne-CT.com/Images/Dipole.gif
                    >
                    > I know many folks swear by them, but I've found that if the antenna
                    > is cut right, and if I let about ten or twenty feet of coax lie on
                    the
                    > ground as it runs into my basement window, baluns seem to make
                    > zero difference in real-world on-the-air performance. That I can
                    > observe, anyway.
                    >
                    > My dipoles are usually somewhat "NVIS-y" about 1/4 wave off the
                    > earth or even a bit less for the 80 meter job. The way the
                    property
                    > here is structured, there is a narrow woodsy part circling the open
                    > lawn-y part in the center where the house is. So, coax dropping
                    > down into the woods, and running across the 10 0r 20 feet of grass
                    > between is simply easy.
                    >
                    > My working theory is that the section of coax laying in the grass
                    > is a lossy choke for any RF flowing on the outside of the coax.
                    >
                    > Dunno, but it seems to work. It's useful lightning protection,
                    too.
                    > The lightning has a lot of opportunity to jump to earth before
                    > reaching the window. That, and I never leave the radios connected
                    > to any antennas if I'm not here. I have a disconnect panel at the
                    > window, and I just let the coaxes drop away from the disconnect
                    > panel, providing about three feet of physical separation when
                    they're
                    > all unplugged.
                    >
                    > Nothing can handle or survive a direct hit. But these kinds of
                    > procedures will save your gear when a nearby hit---50 yards or
                    > less---happens. Those kinds if hits are far more common.
                    >
                    > 73
                    > W1WJB
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    > ----- Original Message -----
                    > From: "Paul Shinn" <subscriptions@...>
                    > To: <RADIOSHACKDX394@yahoogroups.com>
                    > Sent: Saturday, February 03, 2007 11:34 AM
                    > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                    >
                    >
                    > > A 1K resistor in the radio is not as good of a drain as a 0 ohm
                    (at
                    > > DC) path at the feedpoint.
                    > >
                    > >
                    > > --- In RADIOSHACKDX394@yahoogroups.com, "Another Old Codger"
                    > > <clattering.ford@> wrote:
                    > > >
                    > > > It's not the DC path that it helps, that is already covered by
                    > > static
                    > > > discharge resistors fitted on all antenna inputs, the balun
                    > > > compensates for the unbalance of the coax feeder and prevents
                    > > current
                    > > > travelling on the screen of the feeder.
                    > > >
                    > > > Any good antenna book will give a full explanation.
                    > > >
                    > > > As far as the static discharge resistors are concerned they are
                    > > > mandatory in most countries to prevent the build up of
                    dangerous
                    > > > static on the feeder.
                    > > >
                    > > > One of the amazing things about Ham Radio is the vast quantity
                    of
                    > > > excellent books available covering every aspect of the Hobby,
                    and
                    > > > compared with the price of most Ham gear the books are a low
                    cost.
                    > > >
                    > > > Ron.
                    > > > ----- Original Message -----
                    > > > From: "Paul Shinn" <subscriptions@>
                    > > > To: <RADIOSHACKDX394@yahoogroups.com>
                    > > > Sent: Thursday, February 01, 2007 3:47 PM
                    > > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                    > > >
                    > > >
                    > > > For receivers, I believe the main advantage of adding a balun
                    (not
                    > > > just some coiled coax) is the static drain to ground. Without
                    the
                    > > > balun, the wire antenna connects to the center of your coax
                    (and
                    > > > directly to your receiver) and the ground to the shield. With
                    the
                    > > > balun, there is a direct DC path from the antenna wire to
                    ground.
                    > > > THAT is probably most responsible for the drastic reduction of
                    > > noise
                    > > > in the receiver.
                    > > >
                    > >
                    > >
                    > >
                    > >
                    > > Trim all but the core of this message when replying to keep
                    replies from
                    > mushrooming in size.
                    > > For archives of prior messages, files, links, photos, user
                    survey, members
                    > info, etc., visit our group on the WWW.
                    > > Yahoo! Groups Links
                    > >
                    > >
                    > >
                    > >
                    > >
                    > >
                    >
                  • Wm Barrett
                    Your view of the Universe and mine seem to differ somewhat. Yours appears to work perfectly for you. This is good. Mine works for me. Has for a very long
                    Message 9 of 15 , Feb 4, 2007
                      Your view of the Universe and mine seem to differ somewhat.
                      Yours appears to work perfectly for you. This is good.

                      Mine works for me. Has for a very long time. This is also good.

                      It's a big, free country.

                      Be happy.

                      73
                      W1WJB


                      ----- Original Message -----
                      From: "Paul Shinn" <subscriptions@...>
                      To: <RADIOSHACKDX394@yahoogroups.com>
                      Sent: Sunday, February 04, 2007 10:58 AM
                      Subject: [RADIOSHACKDX394] Re: to balun or not to balun


                      > My coax from the balun to the shack runs completely under ground
                      > (about 70 feet total) and the balun still made the huge difference.
                      >
                      > Regarding disconnecting coaxes, if the disconnect box is in or on
                      > your house, that leaves lightning right at your doorstep. Unless
                      > the disconnect is at the antenna feedpoint, you are still looking at
                      > a possible problem.
                      >
                      > BTW, you stated "Nothing can handle or survive a direct hit" that is
                      > untrue. I have a Polyphaser right at the balun where the coax
                      > connects to it, and my tower has been hit (I live on top of a
                      > mountain). No radio damage at all. In fact, one of my commercial
                      > sites gets hit all the time, and the radios stay on right through
                      > the strike and don't even know it happened. They DO work.
                      >
                      > No, I do not sell them or have any interest in the company! Just to
                      > squelch that problem.
                      >
                      >
                      > --- In RADIOSHACKDX394@yahoogroups.com, "Wm Barrett" <bill@...>
                      > wrote:
                      > >
                      > > Call me silly, but for decades I've put a 100k resistor at the
                      > dipole's
                      > > feedpoint. I use a center insulator made up of PVC pipe which
                      > seals
                      > > the feedpoint off from weather. I've never botthered with baluns.
                      > >
                      > > http://www.StudioOne-CT.com/Images/Dipole.gif
                      > >
                      > > I know many folks swear by them, but I've found that if the antenna
                      > > is cut right, and if I let about ten or twenty feet of coax lie on
                      > the
                      > > ground as it runs into my basement window, baluns seem to make
                      > > zero difference in real-world on-the-air performance. That I can
                      > > observe, anyway.
                      > >
                      > > My dipoles are usually somewhat "NVIS-y" about 1/4 wave off the
                      > > earth or even a bit less for the 80 meter job. The way the
                      > property
                      > > here is structured, there is a narrow woodsy part circling the open
                      > > lawn-y part in the center where the house is. So, coax dropping
                      > > down into the woods, and running across the 10 0r 20 feet of grass
                      > > between is simply easy.
                      > >
                      > > My working theory is that the section of coax laying in the grass
                      > > is a lossy choke for any RF flowing on the outside of the coax.
                      > >
                      > > Dunno, but it seems to work. It's useful lightning protection,
                      > too.
                      > > The lightning has a lot of opportunity to jump to earth before
                      > > reaching the window. That, and I never leave the radios connected
                      > > to any antennas if I'm not here. I have a disconnect panel at the
                      > > window, and I just let the coaxes drop away from the disconnect
                      > > panel, providing about three feet of physical separation when
                      > they're
                      > > all unplugged.
                      > >
                      > > Nothing can handle or survive a direct hit. But these kinds of
                      > > procedures will save your gear when a nearby hit---50 yards or
                      > > less---happens. Those kinds if hits are far more common.
                      > >
                      > > 73
                      > > W1WJB
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > ----- Original Message -----
                      > > From: "Paul Shinn" <subscriptions@...>
                      > > To: <RADIOSHACKDX394@yahoogroups.com>
                      > > Sent: Saturday, February 03, 2007 11:34 AM
                      > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                      > >
                      > >
                      > > > A 1K resistor in the radio is not as good of a drain as a 0 ohm
                      > (at
                      > > > DC) path at the feedpoint.
                      > > >
                      > > >
                      > > > --- In RADIOSHACKDX394@yahoogroups.com, "Another Old Codger"
                      > > > <clattering.ford@> wrote:
                      > > > >
                      > > > > It's not the DC path that it helps, that is already covered by
                      > > > static
                      > > > > discharge resistors fitted on all antenna inputs, the balun
                      > > > > compensates for the unbalance of the coax feeder and prevents
                      > > > current
                      > > > > travelling on the screen of the feeder.
                      > > > >
                      > > > > Any good antenna book will give a full explanation.
                      > > > >
                      > > > > As far as the static discharge resistors are concerned they are
                      > > > > mandatory in most countries to prevent the build up of
                      > dangerous
                      > > > > static on the feeder.
                      > > > >
                      > > > > One of the amazing things about Ham Radio is the vast quantity
                      > of
                      > > > > excellent books available covering every aspect of the Hobby,
                      > and
                      > > > > compared with the price of most Ham gear the books are a low
                      > cost.
                      > > > >
                      > > > > Ron.
                      > > > > ----- Original Message -----
                      > > > > From: "Paul Shinn" <subscriptions@>
                      > > > > To: <RADIOSHACKDX394@yahoogroups.com>
                      > > > > Sent: Thursday, February 01, 2007 3:47 PM
                      > > > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                      > > > >
                      > > > >
                      > > > > For receivers, I believe the main advantage of adding a balun
                      > (not
                      > > > > just some coiled coax) is the static drain to ground. Without
                      > the
                      > > > > balun, the wire antenna connects to the center of your coax
                      > (and
                      > > > > directly to your receiver) and the ground to the shield. With
                      > the
                      > > > > balun, there is a direct DC path from the antenna wire to
                      > ground.
                      > > > > THAT is probably most responsible for the drastic reduction of
                      > > > noise
                      > > > > in the receiver.
                      > > > >
                      > > >
                      > > >
                      > > >
                      > > >
                      > > > Trim all but the core of this message when replying to keep
                      > replies from
                      > > mushrooming in size.
                      > > > For archives of prior messages, files, links, photos, user
                      > survey, members
                      > > info, etc., visit our group on the WWW.
                      > > > Yahoo! Groups Links
                      > > >
                      > > >
                      > > >
                      > > >
                      > > >
                      > > >
                      > >
                      >
                      >
                      >
                      >
                      > Trim all but the core of this message when replying to keep replies from
                      mushrooming in size.
                      > For archives of prior messages, files, links, photos, user survey, members
                      info, etc., visit our group on the WWW.
                      > Yahoo! Groups Links
                      >
                      >
                      >
                      >
                      >
                      >
                    • Paul Shinn
                      Ha ha!!! Yes, it s true. I live in my own little world, but it s O.K.- They all know me there. As a 25 year broadcast engineer with engineering degree, I
                      Message 10 of 15 , Feb 5, 2007
                        Ha ha!!! Yes, it's true. I live in my own little world, but it's
                        O.K.- They all know me there.

                        As a 25 year broadcast engineer with engineering degree, I have
                        seen/done plenty with antennas. I have designed and/or built a half
                        dozen AM directional arrays and a few diplex installations. I know
                        a bit about lowband antennas too. My 'view of the universe' seems
                        to be the view shared by many other professionals as well.


                        --- In RADIOSHACKDX394@yahoogroups.com, "Wm Barrett" <bill@...>
                        wrote:
                        >
                        > Your view of the Universe and mine seem to differ somewhat.
                        > Yours appears to work perfectly for you. This is good.
                        >
                        > Mine works for me. Has for a very long time. This is also good.
                        >
                        > It's a big, free country.
                        >
                        > Be happy.
                        >
                        > 73
                        > W1WJB
                        >
                        >
                        > ----- Original Message -----
                        > From: "Paul Shinn" <subscriptions@...>
                        > To: <RADIOSHACKDX394@yahoogroups.com>
                        > Sent: Sunday, February 04, 2007 10:58 AM
                        > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                        >
                        >
                        > > My coax from the balun to the shack runs completely under ground
                        > > (about 70 feet total) and the balun still made the huge
                        difference.
                        > >
                        > > Regarding disconnecting coaxes, if the disconnect box is in or on
                        > > your house, that leaves lightning right at your doorstep. Unless
                        > > the disconnect is at the antenna feedpoint, you are still
                        looking at
                        > > a possible problem.
                        > >
                        > > BTW, you stated "Nothing can handle or survive a direct hit"
                        that is
                        > > untrue. I have a Polyphaser right at the balun where the coax
                        > > connects to it, and my tower has been hit (I live on top of a
                        > > mountain). No radio damage at all. In fact, one of my
                        commercial
                        > > sites gets hit all the time, and the radios stay on right through
                        > > the strike and don't even know it happened. They DO work.
                        > >
                        > > No, I do not sell them or have any interest in the company!
                        Just to
                        > > squelch that problem.
                        > >
                        > >
                        > > --- In RADIOSHACKDX394@yahoogroups.com, "Wm Barrett" <bill@>
                        > > wrote:
                        > > >
                        > > > Call me silly, but for decades I've put a 100k resistor at the
                        > > dipole's
                        > > > feedpoint. I use a center insulator made up of PVC pipe which
                        > > seals
                        > > > the feedpoint off from weather. I've never botthered with
                        baluns.
                        > > >
                        > > > http://www.StudioOne-CT.com/Images/Dipole.gif
                        > > >
                        > > > I know many folks swear by them, but I've found that if the
                        antenna
                        > > > is cut right, and if I let about ten or twenty feet of coax
                        lie on
                        > > the
                        > > > ground as it runs into my basement window, baluns seem to make
                        > > > zero difference in real-world on-the-air performance. That I
                        can
                        > > > observe, anyway.
                        > > >
                        > > > My dipoles are usually somewhat "NVIS-y" about 1/4 wave off the
                        > > > earth or even a bit less for the 80 meter job. The way the
                        > > property
                        > > > here is structured, there is a narrow woodsy part circling the
                        open
                        > > > lawn-y part in the center where the house is. So, coax
                        dropping
                        > > > down into the woods, and running across the 10 0r 20 feet of
                        grass
                        > > > between is simply easy.
                        > > >
                        > > > My working theory is that the section of coax laying in the
                        grass
                        > > > is a lossy choke for any RF flowing on the outside of the coax.
                        > > >
                        > > > Dunno, but it seems to work. It's useful lightning protection,
                        > > too.
                        > > > The lightning has a lot of opportunity to jump to earth before
                        > > > reaching the window. That, and I never leave the radios
                        connected
                        > > > to any antennas if I'm not here. I have a disconnect panel at
                        the
                        > > > window, and I just let the coaxes drop away from the disconnect
                        > > > panel, providing about three feet of physical separation when
                        > > they're
                        > > > all unplugged.
                        > > >
                        > > > Nothing can handle or survive a direct hit. But these kinds of
                        > > > procedures will save your gear when a nearby hit---50 yards or
                        > > > less---happens. Those kinds if hits are far more common.
                        > > >
                        > > > 73
                        > > > W1WJB
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > > ----- Original Message -----
                        > > > From: "Paul Shinn" <subscriptions@>
                        > > > To: <RADIOSHACKDX394@yahoogroups.com>
                        > > > Sent: Saturday, February 03, 2007 11:34 AM
                        > > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                        > > >
                        > > >
                        > > > > A 1K resistor in the radio is not as good of a drain as a 0
                        ohm
                        > > (at
                        > > > > DC) path at the feedpoint.
                        > > > >
                        > > > >
                        > > > > --- In RADIOSHACKDX394@yahoogroups.com, "Another Old Codger"
                        > > > > <clattering.ford@> wrote:
                        > > > > >
                        > > > > > It's not the DC path that it helps, that is already
                        covered by
                        > > > > static
                        > > > > > discharge resistors fitted on all antenna inputs, the balun
                        > > > > > compensates for the unbalance of the coax feeder and
                        prevents
                        > > > > current
                        > > > > > travelling on the screen of the feeder.
                        > > > > >
                        > > > > > Any good antenna book will give a full explanation.
                        > > > > >
                        > > > > > As far as the static discharge resistors are concerned
                        they are
                        > > > > > mandatory in most countries to prevent the build up of
                        > > dangerous
                        > > > > > static on the feeder.
                        > > > > >
                        > > > > > One of the amazing things about Ham Radio is the vast
                        quantity
                        > > of
                        > > > > > excellent books available covering every aspect of the
                        Hobby,
                        > > and
                        > > > > > compared with the price of most Ham gear the books are a
                        low
                        > > cost.
                        > > > > >
                        > > > > > Ron.
                        > > > > > ----- Original Message -----
                        > > > > > From: "Paul Shinn" <subscriptions@>
                        > > > > > To: <RADIOSHACKDX394@yahoogroups.com>
                        > > > > > Sent: Thursday, February 01, 2007 3:47 PM
                        > > > > > Subject: [RADIOSHACKDX394] Re: to balun or not to balun
                        > > > > >
                        > > > > >
                        > > > > > For receivers, I believe the main advantage of adding a
                        balun
                        > > (not
                        > > > > > just some coiled coax) is the static drain to ground.
                        Without
                        > > the
                        > > > > > balun, the wire antenna connects to the center of your coax
                        > > (and
                        > > > > > directly to your receiver) and the ground to the shield.
                        With
                        > > the
                        > > > > > balun, there is a direct DC path from the antenna wire to
                        > > ground.
                        > > > > > THAT is probably most responsible for the drastic
                        reduction of
                        > > > > noise
                        > > > > > in the receiver.
                        > > > > >
                        > > > >
                        > > > >
                        > > > >
                        > > > >
                        > > > > Trim all but the core of this message when replying to keep
                        > > replies from
                        > > > mushrooming in size.
                        > > > > For archives of prior messages, files, links, photos, user
                        > > survey, members
                        > > > info, etc., visit our group on the WWW.
                        > > > > Yahoo! Groups Links
                        > > > >
                        > > > >
                        > > > >
                        > > > >
                        > > > >
                        > > > >
                        > > >
                        > >
                        > >
                        > >
                        > >
                        > > Trim all but the core of this message when replying to keep
                        replies from
                        > mushrooming in size.
                        > > For archives of prior messages, files, links, photos, user
                        survey, members
                        > info, etc., visit our group on the WWW.
                        > > Yahoo! Groups Links
                        > >
                        > >
                        > >
                        > >
                        > >
                        > >
                        >
                      • uk_drac
                        Thank you very much every onefor all of your insite .As i thought when i placed this post there is no convincing answer in either direction, the only
                        Message 11 of 15 , Feb 9, 2007
                          Thank you very much every onefor all of your insite .As i thought when
                          i placed this post there is no convincing answer in either direction,
                          the only conclusion i deffinatly, unequivicably, and without doubt have
                          reached is "suck it and see" il give it a go if it works for me il lwet
                          you all know thanks again everyone
                          >
                        Your message has been successfully submitted and would be delivered to recipients shortly.