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Matching resonant antennas

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Ted Roycraft-3

Re: Matching resonant antennas

Walter Maxwell’s interesting book, “Reflections”, has an in-depth
discussion on non-resonant antennas and tuners. Highly recommended.

73, Ted, W2ZK

On Sat, Jul 18, 2020 at 10:05 AM Lyn Norstad <[hidden email]> wrote:

> Exactly.
>
> -----Original Message-----
> From: W2xj [mailto:[hidden email]]
> Sent: Saturday, July 18, 2020 7:37 AM
> To: [hidden email]
> Cc: [hidden email]; [hidden email]
> Subject: Re: [Elecraft] Matching resonant antennas
>
> What is changing is the radiation pattern. As the frequency increases the
> pattern becomes more sidelobes. Some of those sidelobes are bigger than the
> main lobe and they radiate ‘somewhere’.
>
> Sent from my iPhone
>
> > On Jul 17, 2020, at 21:19, Lyn Norstad <[hidden email]> wrote:
> >
> > Barry -
> >
> > +1
> >
> > I use nothing but 600 ohm OWL (True Ladder Line) and a short piece of
> coax connects to a 1:1 / 4:1 hybrid balun to allow matching the impedance
> perfectly with my KAT500.
> >
> > The antenna is a 360' center fed EDZ (design frequency of 3.5 MHz). The
> KAT500 matches it on all bands 160 - 6m (on 15m, it bypasses).
> >
> > The measured performance indicates excellent radiation on all bands.
> >
> > 73
> > Lyn, W0LEN
> >
> >
> > -----Original Message-----
> > From: [hidden email] [mailto:
> [hidden email]] On Behalf Of Barry LaZar
> > Sent: Friday, July 17, 2020 7:44 PM
> > To: [hidden email]
> > Subject: Re: [Elecraft] Matching resonant antennas
> >
> > Wes,
> >
> > You're correct that open wire/ladder line transmission lines are
> > not a panacea. But, in the average ham stations, open wire does overcome
> > high losses with high SWR, or not so high SWR. What is needed is a look
> > at the ARRL Antenna book for transmission line loss/100 ft. as a
> > function of SWR. You see that on 10 meters running 10:1 SWR the total
> > loss is around 1 db. And, as you go to the lower bands, losses become
> > less. Typical 400 Ohm ladder line has a loss of 0.2 db at 10 MHz and 0.6
> > db at 100 MHz. Using these data and a little interpolation, I would use
> > 0.4 db on 10 meters and a 10:1 SWR for this to be 0.8 db of additional
> > loss for a total of about 1.2 db. Yes, I do use a balun and recommend
> > them so add another 0.5 db. Add another 0.5 db for a good tuner and we
> > end up with a total of 2.2 db. on 10 meters and less on 20 and it
> > decomposes to an academic exercise on 40 and down.
> >
> > Coax on 10 starts out with a higher loss/100 feet. I will use what
> > I use here in K3NDM, Times LMR400. That represents 0.4 at 10 MHz. and
> > 1.4 db at 100 MHz. That will yield about 1.2 db/100 ft on 10 meters. Add
> > 0.25 db for a 2:1 SWR and 0.5 for tuner loss and you end up with about
> >
>
>
> ______________________________________________________________
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Lyn WØLEN

Re: Matching resonant antennas

The 428 page "Reflections III" from 2010 is available here in PDF format:

http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Ted Roycraft
Sent: Saturday, July 18, 2020 10:22 AM
To: Elecraft List Server
Subject: Re: [Elecraft] Matching resonant antennas

Walter Maxwell’s interesting book, “Reflections”, has an in-depth
discussion on non-resonant antennas and tuners. Highly recommended.

73, Ted, W2ZK

On Sat, Jul 18, 2020 at 10:05 AM Lyn Norstad <[hidden email]> wrote:

Lyn WØLEN

Re: Matching resonant antennas

M. Walter Maxwell, W2DU (SK) passed away in 2012 at the age of 93. He was still active.

ARRL has a brief bio here:

http://www.arrl.org/news/walt-maxwell-w2du-sk-wrote-reflections

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Lyn Norstad
Sent: Saturday, July 18, 2020 1:10 PM
To: 'Ted Roycraft'; 'Elecraft List Server'
Subject: Re: [Elecraft] Matching resonant antennas

The 428 page "Reflections III" from 2010 is available here in PDF format:

http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Ted Roycraft
Sent: Saturday, July 18, 2020 10:22 AM
To: Elecraft List Server
Subject: Re: [Elecraft] Matching resonant antennas

Walter Maxwell’s interesting book, “Reflections”, has an in-depth
discussion on non-resonant antennas and tuners. Highly recommended.

73, Ted, W2ZK

On Sat, Jul 18, 2020 at 10:05 AM Lyn Norstad <[hidden email]> wrote:

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Roger Steyaert, K7RXV

Re: Matching resonant antennas

I first meet Walt and his sons at Dayton about 10 years before his
death. Walt and his sons were/are some of the finest gentlemen that you
could ever meet. Walt was the type of person who was friends with
everyone he meet. It was a great loss to mankind and amateur radio when
he became a Silent Key.

Roger Steyaert K7RXV

On 7/18/2020 2:54 PM, Lyn Norstad wrote:

> M. Walter Maxwell, W2DU (SK) passed away in 2012 at the age of 93. He was still active.
>
> ARRL has a brief bio here:
>
> http://www.arrl.org/news/walt-maxwell-w2du-sk-wrote-reflections
>
> 73
> Lyn, W0LEN
>
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]] On Behalf Of Lyn Norstad
> Sent: Saturday, July 18, 2020 1:10 PM
> To: 'Ted Roycraft'; 'Elecraft List Server'
> Subject: Re: [Elecraft] Matching resonant antennas
>
> The 428 page "Reflections III" from 2010 is available here in PDF format:
>
> http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf
>
> 73
> Lyn, W0LEN
>
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]] On Behalf Of Ted Roycraft
> Sent: Saturday, July 18, 2020 10:22 AM
> To: Elecraft List Server
> Subject: Re: [Elecraft] Matching resonant antennas
>
> Walter Maxwell’s interesting book, “Reflections”, has an in-depth
> discussion on non-resonant antennas and tuners. Highly recommended.
>
> 73, Ted, W2ZK
>
> On Sat, Jul 18, 2020 at 10:05 AM Lyn Norstad <[hidden email]> wrote:
>
>> Exactly.
>>
>> -----Original Message-----
>> From: W2xj [mailto:[hidden email]]
>> Sent: Saturday, July 18, 2020 7:37 AM
>> To: [hidden email]
>> Cc: [hidden email]; [hidden email]
>> Subject: Re: [Elecraft] Matching resonant antennas
>>
>> What is changing is the radiation pattern. As the frequency increases the
>> pattern becomes more sidelobes. Some of those sidelobes are bigger than the
>> main lobe and they radiate ‘somewhere’.
>>
>> Sent from my iPhone
>>
>>> On Jul 17, 2020, at 21:19, Lyn Norstad <[hidden email]> wrote:
>>>
>>> Barry -
>>>
>>> +1
>>>
>>> I use nothing but 600 ohm OWL (True Ladder Line) and a short piece of
>> coax connects to a 1:1 / 4:1 hybrid balun to allow matching the impedance
>> perfectly with my KAT500.
>>> The antenna is a 360' center fed EDZ (design frequency of 3.5 MHz). The
>> KAT500 matches it on all bands 160 - 6m (on 15m, it bypasses).
>>> The measured performance indicates excellent radiation on all bands.
>>>
>>> 73
>>> Lyn, W0LEN
>>>
>>>
>>> -----Original Message-----
>>> From: [hidden email] [mailto:
>> [hidden email]] On Behalf Of Barry LaZar
>>> Sent: Friday, July 17, 2020 7:44 PM
>>> To: [hidden email]
>>> Subject: Re: [Elecraft] Matching resonant antennas
>>>
>>> Wes,
>>>
>>> You're correct that open wire/ladder line transmission lines are
>>> not a panacea. But, in the average ham stations, open wire does overcome
>>> high losses with high SWR, or not so high SWR. What is needed is a look
>>> at the ARRL Antenna book for transmission line loss/100 ft. as a
>>> function of SWR. You see that on 10 meters running 10:1 SWR the total
>>> loss is around 1 db. And, as you go to the lower bands, losses become
>>> less. Typical 400 Ohm ladder line has a loss of 0.2 db at 10 MHz and 0.6
>>> db at 100 MHz. Using these data and a little interpolation, I would use
>>> 0.4 db on 10 meters and a 10:1 SWR for this to be 0.8 db of additional
>>> loss for a total of about 1.2 db. Yes, I do use a balun and recommend
>>> them so add another 0.5 db. Add another 0.5 db for a good tuner and we
>>> end up with a total of 2.2 db. on 10 meters and less on 20 and it
>>> decomposes to an academic exercise on 40 and down.
>>>
>>> Coax on 10 starts out with a higher loss/100 feet. I will use what
>>> I use here in K3NDM, Times LMR400. That represents 0.4 at 10 MHz. and
>>> 1.4 db at 100 MHz. That will yield about 1.2 db/100 ft on 10 meters. Add
>>> 0.25 db for a 2:1 SWR and 0.5 for tuner loss and you end up with about
>>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
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> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
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> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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Wes Stewart-2

Re: Matching resonant antennas

In reply to this post by Lyn WØLEN

Walt and I corresponded quite a bit at one time. I sent my copy of the original
"Reflections" to him and asked him to sign it. He sent it back with a lovely
inscription. When Reflections II came out he sent me an unsolicited, inscribed
copy. He was quite pained by the ARRL's repudiation of his work. Pity.

Wes N7Ws

On 7/18/2020 11:54 AM, Lyn Norstad wrote:
> M. Walter Maxwell, W2DU (SK) passed away in 2012 at the age of 93. He was still active.
>
> ARRL has a brief bio here:
>
> http://www.arrl.org/news/walt-maxwell-w2du-sk-wrote-reflections
>
> 73
> Lyn, W0LEN
>

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K8TE

Re: Matching resonant antennas

In reply to this post by Lyn WØLEN

Lyn,

How do you measure your antenna's performance?

In many cases, not necessarily yours, antenna performance seems to be based
on countries worked, achieving WAS/DXCC, "It's way better than last year's
antenna.", or "I worked Pitcarin Island last week." None of these
"measures" are meaningful. I am a big proponent of having a half-wave
dipole as one's "standard" antenna then using the RBN, WSPRLite, etc. to
capture same-time data on the performance of each antenna over time.

In other words, to say one's antenna works, is meaningless. To say it works
well is also meaningless. To say it works better than...can have some value
and perhaps even meaning.

73, Bill, K8TE

--
Sent from: http://elecraft.365791.n2.nabble.com/
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Lyn WØLEN

Re: Matching resonant antennas

Ken -

You are absolutely right, and I totally agree that there needs to be
something to compare to in order to evaluate performance in a meaningful
way. My mistake was in assuming that my judgment, after 50 + years of doing
this, would be accepted without laying out all the details, especially when
combined with actual on-air performance (during times of less favorable
propagation).

So let me add to my prior post that I have spent a great deal of time with
different "simple wire antennas" including inverted-V, sloper, end-fed, G5RV
and yes ... several different "true" dipoles. Some single band, some
resonant, some not, some with traps. And a few verticals with traps, base
loading, center loading and top loading. And one three element tri-bander
at about 55 feet.

I am basing my opinion of this current EDZ on my experiences with those.
That being said, I do not currently have any of those in place in order to
facilitate an actual A/B test under exact same conditions. Nor do I plan to
go to the cost or trouble to do so in order to satisfy the 5% of me that
thinks it might be meaningful.

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of K8TE
Sent: Saturday, July 18, 2020 9:57 PM
To: [hidden email]
Subject: Re: [Elecraft] Matching resonant antennas

Lyn,

How do you measure your antenna's performance?

In many cases, not necessarily yours, antenna performance seems to be based
on countries worked, achieving WAS/DXCC, "It's way better than last year's
antenna.", or "I worked Pitcarin Island last week." None of these
"measures" are meaningful. I am a big proponent of having a half-wave
dipole as one's "standard" antenna then using the RBN, WSPRLite, etc. to
capture same-time data on the performance of each antenna over time.

In other words, to say one's antenna works, is meaningless. To say it works
well is also meaningless. To say it works better than...can have some value
and perhaps even meaning.

73, Bill, K8TE

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alorona

Re: Matching resonant antennas

In reply to this post by Wes Stewart-2

Using AC6LA's Line Loss calculator, and making the following assumptions:

Line impedance: 420 ohms, (1/4" copper pipe spaced 4 inches apart)
SWR at antenna: 14.0 (Z = 30 ohms)
Line attenuation: 0.0266 dB/100 feet (Duffy, "RF Two Wire Transmission Line Loss Calculator", owenduffy.net/calc/tl/twllc.htm)
Length of line: 500 feet (conservative estimate that probably represents a worst-case?)
Frequency: 10 MHz
___________________________

Total Line Loss = 0.891 dB

>>>I've seen pictures of those SW transmitting plants and always assumed that they
>>>must have been very efficient. Upon reflection---no pun intended---now I'm not
>>>so sure.
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