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Is 1.1:1 the perfect tune?

Tokin

The Man With No Shoes
Oct 31, 2019
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So i can get lower than 1.1 which of course lowers my reflect watts to almost zero but does tuning lower than 1.1 negatively affect other parameters such as reactance and phase?
Is the 1.10 - 1.19 range where i find that sweet spot where all the parameters align or am i just jerking off?
 

There is a thread around here somewhere that talks about SWR verses resonance. Basically the parameter to chase is resonance at the center frequency of the range you want to use. Hopefully the SWR at this point is acceptable, if not then something else needs to be done to get a good match besides changing the element length. If it is a vertical, a coil could be added to the feed point. If you have a gamma match, dial it in and you should be good. I don't think going below 1.1 would make any noticable difference.

Good to see you here, hope you are getting some good DX in.
Chris
 
There is a thread around here somewhere that talks about SWR verses resonance. Basically the parameter to chase is resonance at the center frequency of the range you want to use. Hopefully the SWR at this point is acceptable, if not then something else needs to be done to get a good match besides changing the element length. If it is a vertical, a coil could be added to the feed point. If you have a gamma match, dial it in and you should be good. I don't think going below 1.1 would make any noticable difference.

Good to see you here, hope you are getting some good DX in.
Chris
Good to see you too. Certain elements here i miss and others I don't though I do refer alot of people here to get accurate info. Im like a tropical rash that just wont go away lol
 
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There is no noticeable difference between SWR and Resonance.

There is also no noticeable difference between 2:1 SWR and 1:1 SWR.

The difference in both of the above is so small you will never notice the difference. In most cases, getting that antenna 5 feet higher will make more of a difference than where within that range you tune the antenna.

Basically, set it to whatever you feel comfortable with and don't worry about it unless something changes unexpectedly.


The DB
 
If ya already have a swr of 1.1 trying to improve that is a waste.in fact anything below a 1.5 is acceptable.I always try to keep my reactance or X as low as possible ,even if it slightly raises swr.next I try to get my impedance or R as close to 50 ohms as possible. All this before I worry about swr. Only time I put see first if its above a 1.5 . Then I go over my install again making sure I didn't miss something.....now this is just how I've done since the early 90sand it works for me
 
anything below a 1.5 is acceptable
Really, anything below 2 is acceptable. A 2:1 SWR ratio will not produce enough reflected power to damage anything, and as stated above, the small power loss that results isn't noticeable in the real world.

Everyone likes to see a really really low SWR, but it's not anywhere near as important is some would have you believe !
Spending hours and hours trying to reduce it from 1.1 to a flat 1 is a complete waste of time.
 
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This
There is no noticeable difference between SWR and Resonance.

There is also no noticeable difference between 2:1 SWR and 1:1 SWR.

The difference in both of the above is so small you will never notice the difference. In most cases, getting that antenna 5 feet higher will make more of a difference than where within that range you tune the antenna.

Basically, set it to whatever you feel comfortable with and don't worry about it unless something changes unexpectedly.


The DB
It has become a 11 meter thing to have SWR as low as possible, often you will see people saying anything over 1:5 will blow up your radio.
I think this comes from years ago when guys were doing shoot outs and running Toshiba's on the ragged edge at 21 volts with insane drive levels....
In that situation you had to have all of your ducks in a row to get them to last 20-30 seconds in a keydown

73
Jeff
 
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Uh, why is nobody asking how accurate your SWR reading is?

Every kind of measurement will exhibit some margin of error. A SWR meter is no exception. What level of accuracy does your SWR meter provide? 10 percent? 5? 20?

This sounds a little like trying to make a measurement to 1/32 of an inch with a rule marked only every 1/8 inch.

I sell PL259 plugs with a 5% resistor to check SWR meter accuracy on fleabay. More than a few simple SWR meters we tried would show a perfect match at 40 or 60 ohms. A "perfect" one-to-one may warm your heart, but how close to an actual 50 ohms is this reading? I'll guess that 10 percent is probably an average sort of error.

But nobody will ever hear that difference anyway. Just the same, obsessing over a difference too small to measure in an accurate way is pretty much a waste of time. Entertaining, maybe but it doesn't offer a practical benefit.

73
 
I think this comes from years ago when guys were doing shoot outs and running Toshiba's on the ragged edge at 21 volts with insane drive levels....

I remember those days. Said amps would be run on the ragged edge to the point where everything had to be perfect, and even with said perfection, many dind't last long even when run at 12 volts and under ideal circumstances. The problem is many people bought said amps thinking they were "the best". A local CB shop I spent a lot of time at (I was good friends with the tech) spent more time working on a few brands of amps then all of his CB's combined... The owners of said amps just didn't understand why they had so many problems, but at the same time wouldn't listen when it was explained to them...

Uh, why is nobody asking how accurate your SWR reading is?

I actually asked this question once. Then compared a bunch of SWR meters that have fallen into my lap over the previous decades (many of which had an unknown history and sat in my basement since I got them). I used four different calibrated loads of various impedances. They were all pretty much spot on. With such consistent results across said meters that weren't exactly stored in good environments I just didn't worry about it after that. There is also the fact that I had my first VNA at that point, which also matched the meters when it came to SWR results.

Maybe I just got lucky and only good meters fell into my hands over the years?

Another test I did at the time was measure the change in SWR and loss said meters cause for the devices on the radio side. None of them had drastic changes, but in general, the smaller meters had less of a change in SWR and less additional loss than the larger meters. Yep, that meter you are using will affect the SWR your radio/amp sees, at least to some small degree.

I'm pretty sure I posted about the experiment here on this forum, but it would have been decades ago at this point so good luck finding it.


The DB
 

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