Bob, the thing is, that when I push the tune button on the 
external tuner, it doesn't chatter like it did when connected to 
the TS480 when it was trying to tune to the antenna.  It's kind 
of caused me to wonder if it is working or not, but it seems to 
be working at least some times.  Jim WA6EKS

 ----- Original Message -----
From: Bob Tinney <[log in to unmask]
To: [log in to unmask]
Date sent: Wed, 26 Nov 2014 21:34:05 -0500
Subject: Re: Question about using an external tuner with the 
TS590

Jim,

I prefer an external tuner as they are not as lossy as most 
internal
tuners.  My 590 tuner drops my power output by 10 to 15 watts and 
my
Palstar 2K tuner shows no measurable loss in to a dummy load.  
One thing
that can get a ham in trouble is if you have both your internal 
tuner
and external tuner both turned on.  The output on the rig could 
get such
a high impedence that it could arc over or blow a fixed 
capacitor.

Bob, K8LR, [log in to unmask]

On 11/26/2014 9:23 PM, Jim Gammon wrote:
 I am using the internal tuner in my Ts 590 but still have my
 small external tuner in line that I used with the TS 480.  I 
have
 noticed that I don't get much action from the external tuner 
like
 I used to get when it was connected to the 480.  Seems like the
 internal tuner in the 590 is handling most or all of the tuning.
 My question is, can I take the external tuner out of the line?
 Thanks for your thoughts, Jim WA6EKS

   ----- Original Message -----
 From: Bob Tinney <[log in to unmask]
 To: [log in to unmask]
 Date sent: Wed, 26 Nov 2014 21:15:50 -0500
 Subject: Re: SWR, antenna tuners, and reflected power

 I have to add something here,  I used to think that you had to
 have a
 perfect match to maximize efficiency.  But I now realize that if
 you
 have a good, wide range, antenna tuner, you can match almost
 anything.
 You can even load up an 8 foot whip on 160 meters, but the
 radiation
 efficiency will be very low and your tuner will get very hot or
 arc.  I
 have an Alex loop that is 3 feet in diameter and it gets out
 surprisingly well even on 40 meters, but you can only use up to
 20 watts
 do to the close spacing in the tuning capacitor on the loop.

 Bob, K8LR, [log in to unmask]

 On 11/26/2014 4:24 PM, Tom Behler wrote:
   Ron:

   Thanks for the excellent concept review on SWR, reflected 
power,
 and antenna
   tuners.

   We all need reminders about this sort of thing from time to
 time.

   In fact, I'm now thinking of making some modifications to my
 station, and am
   trying to decide whether I can effectively do so with my 
current
 antenna
   arrangement.  As you may recall, I use an Alpha Delta DXCC
 nulti-band dipole
   on 40 through 10 meters, and a Cobra ultralite senior antenna,
 mainly for
   the lower bands.

   While these antennas have kept me on the air on the HF bands
 over the past
   few years, I do wonder sometimes whether I might try something
 else to
   improve my situation.  I do have limited space here, though,
 which makes the
   issue of alternate wire antennas a bit challenging.  A tower 
and
 beam are
   also out of the question at this time for financial and other
 more practical
   reasons.


   Anyway, your remarks are quite timely here, so thanks for
 sharing them.

   Tom Behler: KB8TYJ


   -----Original Message-----
   From: For blind ham radio operators
 [mailto:[log in to unmask]]
   On Behalf Of Dr.  Ronald E.  Milliman]\\`
   Sent: Wednesday, November 26, 2014 4:07 PM
   To: [log in to unmask]
   Subject: SWR, antenna tuners, and reflected power

   I am sure most of you know all about SWR (i.e.  Standing Wave
 Ratio), antenna
   tuners, and reflected power.  However, it might be worth our
 discussing it
   anyway for the benefit of those who might not be as familiar
 with these
   relationships as others.  Many of us use antenna tuners, both
 manual and
   automatic, for obtaining the best possible impedance match at
 the output
   point of our transceivers with the objective of getting the 
SWR
 as close to
   1.0 to 1 as we can.  A perfect match for most rigs is when the
 transceiver
   sees a 50 ohm load at its output.  Anything above a 1:1 SWR
 represents some
   level of mismatch.  Most of our transceivers can tolerate some
 mismatch
   before it begins to reduce the power output as a means of
 protecting the
   circuitry of the transceiver, and if the SWR or mismatch gets
 high enough,
   it will cause the transceiver to reduce its power output to
 zero.  Many of us
   have transceivers, like the Kenwood TS-590 and similar rigs,
 that have
   built-in automatic antenna tuners.  These tuners work 
extremely
 well for
   matching the impedance presented to the transceiver at its
 output, providing
   this mismatch isn't too high.  How much is too high varies to
 some extent
   from one make and model of transceiver to another.  If the
 mismatch is so
   large that the rigs internal automatic tuner cannot bring the
 SWR down
   within an acceptable level, you are faced with either 
adjusting
 your antenna
   to achieve a better match at the point where the feedline
 connects to the
   antenna, or you will need to obtain an external tuner to do 
the
 job.
   External tuners, whether manual or automatic, tend to have 
much
 wider ranges
   for matching the impedance of the feedline to the 50 ohms the
 transceiver
   wants to see at its output.  A match at the transceiver's 
output
 does not
   mean there is a match at the point where the feedline actually
 connects to
   the antenna.  Even if the impedance at the output of the
 transceiver is
   matched perfectly with an antenna tuner, there can be a very
 substantial
   mismatch at the other end of the feedline where it connects to
 the antenna.
   The larger this latter mismatch, the less actual power will be
 radiated by
   the antenna and the more power from the transceiver will be
 reflected back
   or remain in the feedline.  What happens to the reflected 
power
 depends
   largely on the type of feedline used.  The difference between
 the power
   radiated by the antenna and the output power of the 
transceiver
 is the
   reflected power and may be totally lost power, depending upon
 the loss
   rating of the feedline.  If coax is used for the feedline, 
this
 reflected
   power ends up dissipating as heat in the coax and is pretty 
much
 totally
   lost power.  If this heat is more than the coax can handle, it
 can burn up
   the coax.  In contrast, open wire feedline is considerably 
less
 "lossy", and
   much of the reflected power ends up being radiated by the open
 wire feedline
   as opposed to ending up being dissipated in heat.



   I am building up to two very important points that, in my
 opinion, do not
   received nearly as much attention as they should.  The first
 point is that
   reflected power is not good for your transceiver, or if you 
are
 using a
   linear amplifier, it is not good for your amp.  If you are 
using
 a tube-type
   linear, it can handle or tolerate more reflected power than 
the
 solid-state
   type amps, but regardless, reflected power is bad for your rig
 and it is bad
   for your amp.  Here is    my second point: just because your
 antenna tuner is
   able to get the SWR down to 1.0 to 1 or an acceptable level at
 the output of
   your transceiver or amp, that does not mean the reflected 
power
 is zero or
   reduced to an acceptable level.  Most rigs and amps today have
 built-in
   protection circuits that detect high SWR and high reflected
 power, and they
   will shut completely down if either the SWR or reflected power
 is too high.
   For example, I have a Kenwood TS-590 driving an Ameritron
 ALS-600, and my
   antenna is an 80 meter, full-wave loop.  I feed the loop 
antenna
 with 50 ohm
   coax and use a 2.5 to 1 matching ballun at the feedpoint of 
the
 antenna.  The
   loop works extremely well on all bands 80 through 10 meters,
 including the
   WARP bands.  However, there is a sizable mismatch on some 
bands
 at the
   feedpoint of the antenna.  Without an antenna tuner, this
 mismatch would
   present such a high SWR at the output of the transceiver or
 amplifier that
   the protection circuits would reduce the power to zero or, in
 the case of
   the amp, it would kick it off.  The mismatch is so high that 
the
 internal
   tuner of the TS-590 cannot handle it.  So, I use a LDG 
AT1000PRO
 II external,
   automatic antenna tuner, which has a much wider matching 
range,
 and it can
   handle the mismatch and the power of the ALS-600 just fine.
 However, even
   though I am able to get my SWR down to 1.0 to 1 on some bands
 and 1.5 to 1
   or better on the others, I cannot run the amp at full power
 because if I do,
   the reflected power is so high, over 50 watts, that it causes 
my
 ALS-600 to
   kick off.  Therefore, I am forced to reduce my output power 
down
 to the point
   where the reflected power is low enough that it won't shut the
 amp down.
   Consequently, instead of putting out 600 watts from the amp, I
 have to
   reduce the power to where I am putting out only about 300 
watts.
 This keeps
   my reflected power level below 50 watts, which is the critical
 level for the
   ALS-600 amp, keeping it from completely shutting down.



   Many years ago, when I was a young, foolish teenager, I put up
 an antenna
   that had such a high SWR that I could get RF burns from the
 Microphone of my
   transmitter.  The transmitter was a Heathkit DX-40, which had 
a
 PI-output
   circuit that would allow me to load-up about anything for an
 antenna, but
   back in those days, there were no protection circuits to
 automatically shut
   the rig down if the SWR or reflected power was excessive.  As 
a
 result, the
   high SWR and reflected power from trying to load and extremely
 mismatched
   antenna caused my tank coil to get so hot that it melted the
 plastic
   insulators that separated the windings of the tank coil; this
 caused the
   tank coil to short, which, in turn, created a chain reaction,
 ending up in
   wiping out the entire power supply.  My point is to simply
 illustrate what
   high SWR and reflected power could do to your transceiver or 
amp
 if it
   weren't for the protection circuits that are built into the
 modern gear.
   However, even with the protection circuits, it is important to
 strive to
   achieve the best possible resonant frequency match with your
 antenna and
   then, between the feedline and your antenna and again between
 the feedline
   and the output of your equipment.



   I've had three people write to me off list asking me questions
 that related
   to this whole topic, and so, I thought I would simply write 
this
 up and post
   it to the list.  I'm not trying to show-off what I know; 
rather,
 I might be
   showing-off what I don't know because there is a lot more 
about
 this stuff
   that I know very little about, and I am absolutely certain 
that
 many of you
   know tons more about some of this stuff than I do.  I'm just
 trying to be
   helpful to some of the people that might be new that do not
 understand some
   of these things.











   Dr.  Ronald E.  Milliman

   Retired Professor of Marketing



   President: Millitronics, Inc.  (millitronics.biz)

   President: South Central Kentucky Council of the Blind
 (SCKCB.ORG)