http://elecraft.85.s1.nabble.com/Matching-resonant-antennas-tp7663149p7663328.html
surprised it's working out well for you. Not every ham has the liberty
to put up, grow, an antenna farm. I am in that position. I have only two
with a remote tuner. I also have 5 elevated radials of varying length
connected to the remote tuner , just because. Collectively, they work
out well. It sometimes amazes me how some wire in a tree or two can be
used to reach out and touch people. :-) I have never used a beam, but I
100% duty cycle digital modes. All of my contesting and DX work has been
at the 100 Watt level, except Field Day when I run QRP. So, good going
> 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
> 1.95 at a 2:1 SWR.
>
> Here coax wins IFF the SWR remains less than 2:1 which won't happen
> over the entire commonly used portion of the band. Using ladder line
> vice coax will contain losses over the entire band. This keeps things
> simple and the cost should be a lot less.
>
> As to the RCA station with a 14:1 SWR, they used no balun nor tuner
> as we commonly know them today. The coupling to the final tube(s) were
> balanced and was capable of making the transformation from what the tube
> wanted and the reflected impedance at the transmitter end of the
> transmission line. Ergo, they had a very low loss if using 10 meters
> which they didn't. They typically used frequencies below 18 MHz and a
> slug of power.
>
> Vy 73,
>
> Barry
>
> K3NDM
>
>
> On 7/17/2020 6:57 PM, Wes wrote:
>> I wrote about some of this in my paper ARRL Antenna Compendium paper
>> on ladder line 20 years ago.
https://sadxa.org/n7ws/Ladder_Line.pdf>>
>> 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. If losses mounted up, (which they
>> most certainly did at 14:1 SWR) they had the option of just turning up
>> the wick.
>>
>> Furthermore, as I said in closing: "Contrary to the conventional
>> wisdom, ladder line is not a panacea for every transmission line
>> problem." In the ensuing 20 years, I've become even more convinced of
>> this. When tuner and balun losses are factored into this picture I
>> don't know why anyone would want to use this stuff. I sure don't.
>>
>> I have a KAT500 and use it to tune some way-off resonant antennas (fed
>> with 7/8" Heliax) but I don't delude myself into thinking "I've
>> contained system losses."
>>
>> Wes N7WS
>>
https://www.qrz.com/db/N7WS>>
>>
>> On 7/17/2020 2:32 PM, Barry LaZar wrote:
>>> Resonance is over rated. The problem of believing you must have a
>>> resonant antenna arose with the use of coax cable began. High SWRs
>>> causes high system losses.
>>>
>>> Prior to the widespread use of coax, open wire was used and few
>>> antenna systems were really resonant, and nor were they reflecting a
>>> 1:1 SWR. Back then, no one cared as tubes were used and pi-net or
>>> swinging links were used to match to whatever was connected to the
>>> transmitter. In fact, I once visited a site that used rhombic
>>> antennas and Sterba curtains being fed by high power transmitters.
>>> The feed line were copper pipes about 1/4" in diameter and spaced
>>> about 4". The SWR, I was told, was 14:1. I asked if that was a
>>> problem of transferring energy to the system. The answer was no as
>>> the final output stage could match it and the system losses were low
>>> due to the type of feed line used. This was a lesson I learned 60
>>> years ago and haven't forgotten it. The site was the RCA site the
>>> once stood on Montauck Point on Long Island, New York.
>>>
>>> One point that keeps getting forgotten is the conservation of energy
>>> concept. What that means is energy can only be changed and not lost.
>>> Typically that means transmitter energy would be changed to heat, but
>>> not lost. What is not changed to heat on the coax will make it to the
>>> antenna where it MUST be radiated and not lost. Yhe practical
>>> application of this is use really good coax if you can't get to a
>>> 1:1-2:1 SWR, ot there about. Alternatively, use ladder line and a
>>> current balun. Elecraft tuners easily tune 10:1 SWR which contains
>>> system losses nicely. I have been doing this for a very long time and
>>> have achieved WAS, DXCC phone, DXCC CW, and DXCC digital, and, I'm 13
>>> short on 80 of making 5BDXCC.
>>>
>>> 73,
>>>
>>> Barry
>>>
>>> K3NDM
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