I've watched that video before. And I concur on the imaginary "0" SWR claims from other cbers.
I've heard a lot of them claim their SWR is 0 or flat, no SWR. I normally laugh when I hear them say that and then proceed to explain to them what I think is correct. Which I always get criticized on.
My theory:
A perfect SWR is not 0, or a 1:0.
First off, a perfect SWR is equal to a 1:1.
1 is not equal to 0, and 0 is not equal to 1, therefore a 1:0 is not a perfect SWR because it's not at unity, the numbers don't equal each other.
A perfect SWR, in my opinion is when the resistance AND reactance both (impedance) are 50 ohms resistive component and 0 ohms reactive component. A 1:1, and match what the radio or swr meter should see. Although we all know swr meters won't show the reactive component (capacitive or inductive), so you never know what the reactance is, because all the swr meter looks for is the resistance of the load, not the reactance. Only an analyzer will show both.
I've also heard so many people claim their IMPEDANCE is 50 ohms, again I laugh because they're confusing the resistance component as the impedance. The impedance isn't just resistance, it's a combination of resistance AND reactance (+-j).
Resistance = resistance
Reactance = capacitance or inductance
Impedance = combination of resistance AND reactance.
Therefore, to have a perfect SWR, the load must equal what the xmitter or analyzer needs to see for maximum performance, which is close to 50 ohms resistance as possible along with a reactance as close to 0 ohms as possible.
Many will argue the above, but we all have our own opinions on SWR theory.
I actually tested this out on my truck one day.
I used a 102" stainless steel whip mounted on the rear passenger bed rail of the truck, and an analyzer.
I connected the analyzer directly into the base of the whip, no jumpers or adapters were used. I then tried 4 different lengths of the same type coax.
At the antenna input, with analyzer directly connected to it the resistance was 49.45ohms and the reactance was around .95ohms, I know, awesome right, lol...
I then hooked a 9ft length of RG8X (VF = .82) to the antenna base, then checked the impedance at the radio end of that coax with the analyzer. The resistance was very close to the original resistance at the antenna, but the reactance was up around 17ohms, although the SWR still showed decent.
I then replaced the 9ft coax with an 18ft length (never did like running coax lengths that are equal to a physical half wavelength) of the same type coax. The results were different and not desirable to me.
The resistance went to around 53 ohms, but the reactance skyrocketed up to around 28 ohms, yuk.. No where near what it is at the antenna.
I then replaced that 18ft coax with a 21ft piece of the same type of coax (heard others say that 21ft is a magic number for 102" whips). The resistance leveled out to 50 ohms, but the reactance dropped to around 12 ohms, still no where near the reactance at the antenna itself.
I then decided to try nulling my coax of the same type by using the velocity factor figure according to a formula I once heard about. My length came out to be 15ft 2.25in. I installed that length, and low & behold the resistance stayed between 49 ohms and 50 ohms (can't rightly remember the exact number) but the reactance showed ALMOST identical to what it was at the antenna. About 1ohm reactance, which was very close to the .95ohm reactance at the antenna.
Been running that length every since, and several others tried it out also on their base setups by replacing all their coax from the antenna run to their jumper runs doing the same identical thing I did. They all improved on xmit signal by 1db to 2db more on everyone and their receive improved by about the same.
I've explained to them that the coax manufacturers don't list the VF just to list it, just so you'll know what it is, for no reason. They list that number for a reason, so you can tune your coax to remove any reactance (capacitance or inductance) that may be present in the coax for a given frequency. I've also explained to them that antenna manufacturers design their antennas for the lowest reactance as possible to improve the performance, therefore you can't just throw any old length of coax onto that antenna because you'll be introducing reactance back to the antenna that was designed to have the least amount of reactance as possible, thereby hindering the performance of the entire system. I've also explained that mixing coax types is a no no, because you're combining differing reactances.
A typical SWR meter is a dumb device, as it doesn't present the reactance present in the system.
The radio expects to see 50ohms resistance with 0ohms reactance, as with the antenna designers objectives in designing their antennas to be as close to 50ohms resistance and as close to 0ohms reactance. Why introduce that reactance (which cancels out performance) to a system that is designed to not want any of that reactance?
These are just my opinions of the theory of SWR, not written in stone, so please don't bash me for my opinions. Like I said, I tested it in real time with an analyzer and on the air tests, along with a few of our locals, and it has proven to work for us.
I've heard a lot of them claim their SWR is 0 or flat, no SWR. I normally laugh when I hear them say that and then proceed to explain to them what I think is correct. Which I always get criticized on.
My theory:
A perfect SWR is not 0, or a 1:0.
First off, a perfect SWR is equal to a 1:1.
1 is not equal to 0, and 0 is not equal to 1, therefore a 1:0 is not a perfect SWR because it's not at unity, the numbers don't equal each other.
A perfect SWR, in my opinion is when the resistance AND reactance both (impedance) are 50 ohms resistive component and 0 ohms reactive component. A 1:1, and match what the radio or swr meter should see. Although we all know swr meters won't show the reactive component (capacitive or inductive), so you never know what the reactance is, because all the swr meter looks for is the resistance of the load, not the reactance. Only an analyzer will show both.
I've also heard so many people claim their IMPEDANCE is 50 ohms, again I laugh because they're confusing the resistance component as the impedance. The impedance isn't just resistance, it's a combination of resistance AND reactance (+-j).
Resistance = resistance
Reactance = capacitance or inductance
Impedance = combination of resistance AND reactance.
Therefore, to have a perfect SWR, the load must equal what the xmitter or analyzer needs to see for maximum performance, which is close to 50 ohms resistance as possible along with a reactance as close to 0 ohms as possible.
Many will argue the above, but we all have our own opinions on SWR theory.
I actually tested this out on my truck one day.
I used a 102" stainless steel whip mounted on the rear passenger bed rail of the truck, and an analyzer.
I connected the analyzer directly into the base of the whip, no jumpers or adapters were used. I then tried 4 different lengths of the same type coax.
At the antenna input, with analyzer directly connected to it the resistance was 49.45ohms and the reactance was around .95ohms, I know, awesome right, lol...
I then hooked a 9ft length of RG8X (VF = .82) to the antenna base, then checked the impedance at the radio end of that coax with the analyzer. The resistance was very close to the original resistance at the antenna, but the reactance was up around 17ohms, although the SWR still showed decent.
I then replaced the 9ft coax with an 18ft length (never did like running coax lengths that are equal to a physical half wavelength) of the same type coax. The results were different and not desirable to me.
The resistance went to around 53 ohms, but the reactance skyrocketed up to around 28 ohms, yuk.. No where near what it is at the antenna.
I then replaced that 18ft coax with a 21ft piece of the same type of coax (heard others say that 21ft is a magic number for 102" whips). The resistance leveled out to 50 ohms, but the reactance dropped to around 12 ohms, still no where near the reactance at the antenna itself.
I then decided to try nulling my coax of the same type by using the velocity factor figure according to a formula I once heard about. My length came out to be 15ft 2.25in. I installed that length, and low & behold the resistance stayed between 49 ohms and 50 ohms (can't rightly remember the exact number) but the reactance showed ALMOST identical to what it was at the antenna. About 1ohm reactance, which was very close to the .95ohm reactance at the antenna.
Been running that length every since, and several others tried it out also on their base setups by replacing all their coax from the antenna run to their jumper runs doing the same identical thing I did. They all improved on xmit signal by 1db to 2db more on everyone and their receive improved by about the same.
I've explained to them that the coax manufacturers don't list the VF just to list it, just so you'll know what it is, for no reason. They list that number for a reason, so you can tune your coax to remove any reactance (capacitance or inductance) that may be present in the coax for a given frequency. I've also explained to them that antenna manufacturers design their antennas for the lowest reactance as possible to improve the performance, therefore you can't just throw any old length of coax onto that antenna because you'll be introducing reactance back to the antenna that was designed to have the least amount of reactance as possible, thereby hindering the performance of the entire system. I've also explained that mixing coax types is a no no, because you're combining differing reactances.
A typical SWR meter is a dumb device, as it doesn't present the reactance present in the system.
The radio expects to see 50ohms resistance with 0ohms reactance, as with the antenna designers objectives in designing their antennas to be as close to 50ohms resistance and as close to 0ohms reactance. Why introduce that reactance (which cancels out performance) to a system that is designed to not want any of that reactance?
These are just my opinions of the theory of SWR, not written in stone, so please don't bash me for my opinions. Like I said, I tested it in real time with an analyzer and on the air tests, along with a few of our locals, and it has proven to work for us.
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