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what is your vswr at the antenna?

The DB

Sr. Member
Aug 14, 2011
2,008
1,536
193
St. Louis, MO
You solve it, either yourself or Bob. Give the answer with the method and calculations.

Here is a white paper that Bob85 used to get his answer, that was already posted in post 9 of this thread...

http://bird-electronic.com/en/Resources/~/media/Bird/Files/PDF/Resources/white-papers/VSWR-Measurements-Using-In-Line-Power-Meters.ashx

I also came up with an answer, and used a different method to get it. Perhaps you should read the posts beyond the first post once again. After all, I see no reason to post what has already been posted in this thread for someone who is acting a lot like a troll.


The DB
 

Slowmover

BANNED
Feb 17, 2015
5,276
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Where the West Begins.
I reckon Bob85 is full of shit. There are not enough parameters to calculate anything. This could be a low and insulting blow against CBers. I could be wrong about this, he may very well believe in his own bullshit. Be aware of people spreading crap, and don't fold to people just because they claim to know more than yourself.


You might take into consideration that this isn’t the typical CB radio forum. I understand what you’ve said — maybe why — and recommend that if radio is your interest, this forum may have more to offer than is apparent at first go-through.

Antennas are a daunting subject.

Please don’t reply. I’ve shot off my mouth in the wrong way elsewhere. Offended when there really wasn’t cause.

.
 

Shadetree Mechanic

Delaware Base Station 808
Oct 23, 2017
5,403
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The First State (Delaware)
I reckon Bob85 is full of shit. There are not enough parameters to calculate anything. This could be a low and insulting blow against CBers. I could be wrong about this, he may very well believe in his own bullshit. Be aware of people spreading crap, and don't fold to people just because they claim to know more than yourself.
The two trains meet in Chicago at exactly 6:23pm.
 

Captain Kilowatt

Professional Amateur
Staff member
Apr 6, 2005
17,045
11,556
823
59
Nova Scotia,Canada
I reckon Bob85 is full of shit. There are not enough parameters to calculate anything. This could be a low and insulting blow against CBers. I could be wrong about this, he may very well believe in his own bullshit. Be aware of people spreading crap, and don't fold to people just because they claim to know more than yourself.

Road Squawker, what I said is correct. Why do you pretend to be some kind of aficionado, the feed line impedance has nothing to do with the fundamentals of standing wave ratio that I was pointing out. Please refrain from crossing out my posts in the future.

Looks like someone has a chip on their shoulder. That chip has a way of getting knocked off. No need for that kind of post at all regardless. Bob83 is indeed one of the more knowledgeable members on this site and just because you don't understand the problem does not mean he is full of bullshit.
 

Flatop

Active Member
Apr 12, 2019
50
37
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Here is a white paper that Bob85 used to get his answer, that was already posted in post 9 of this thread...

http://bird-electronic.com/en/Resources/~/media/Bird/Files/PDF/Resources/white-papers/VSWR-Measurements-Using-In-Line-Power-Meters.ashx

I also came up with an answer, and used a different method to get it. Perhaps you should read the posts beyond the first post once again. After all, I see no reason to post what has already been posted in this thread for someone who is acting a lot like a troll.


The DB
There are too many letters in that PDF, trolls can't read anyway.
 

Flatop

Active Member
Apr 12, 2019
50
37
28
51
You might take into consideration that this isn’t the typical CB radio forum. I understand what you’ve said — maybe why — and recommend that if radio is your interest, this forum may have more to offer than is apparent at first go-through.

Antennas are a daunting subject.

Please don’t reply. I’ve shot off my mouth in the wrong way elsewhere. Offended when there really wasn’t cause.

.
I do not find antennas daunting, you may be speaking for yourself. I do not hang around typical CB forums or any CB forum for that matter. I am not a troll either. What I like to point out is the needless urge for some people to express their incredible knowledge whilst reciting from a book sewn to their chest. It is cringe worthy.
 

Alexis Mercado

Well-Known Member
May 17, 2016
301
167
53
46
VSWR at the antenna ? A VSWR meter placed in an antenna input ? Who do that ? For what purpose ?

Let’s imagine that such person don’t have an antenna analyzer with a short coax jumper at the antenna site in order to adjust it , just use the jumper , maybe 10- 20 feet, installed the VSWR meter, connect from meter to radio, hit the PTT and have a friend tell you how much SWR you have. Just make sure you test the antenna close to QTH . With a short coax jumper you will have an idea of how much VSWR you have at the antenna feed point.

VSWR should not be affected by length of coax cable. Radio signal for sure will. The longer the coax, the bigger the loss in signal reaching the antenna.
 

freecell

BANNED
Apr 6, 2005
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"VSWR should not be affected by length of coax cable." Fortunately it is, anytime the line is not terminated in a load = to the characteristic impedance (Zo) of the feedline or in the case of a feedline with excessive line attenuation losses.

A 500' line of RG-213 will lose 70% of the power produced by the transmitter before it is delivered to the antenna. If the load impedance is anything but a perfect match, additional power will be "displaced" due to reflection from the load back down the line.
 
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