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I am still learning this so forgive me if I am miss something. I am sure someone will correct me if I'm wrong. The way I understand it is:
The physical length of the antenna is correct for 11 meters as the SWR curve is at its lowest on channel 19 of the CB band. When I began bonding the body of the truck (RF grounding) with ground strapping, it changed the size of the counterpoise. It is for the purpose of attempting to make the radiating pattern better and the antenna perform better on TX and RX. But changing the size of the ground plane causes a mismatch of sort. SWR is still lowest on ch 19 but was higher than before RF grounding. The physical length of the whip has not changed. The shunt coil "what I called an inductor" borrows capacitance from the ground plane (truck body) and gives it to the radiating element (whip) and bringing it back into balance, thus lowering the SWR.

<blockquote data-quote="roadrage" data-source="post: 388319" data-attributes="member: 21185">I am still learning this so forgive me if I am miss something.&nbsp; I am sure someone will correct me if I&#039;m wrong.&nbsp; The way I understand it is:The physical length of the antenna is correct for 11 meters as the SWR curve is at its lowest on channel 19 of the CB band.&nbsp; When I began bonding the body of the truck (RF grounding) with ground strapping, it changed the size of the counterpoise.&nbsp; It is for the purpose of attempting to make the radiating pattern better and the antenna perform better on TX and RX.&nbsp; But changing the size of the ground plane causes a mismatch of sort.&nbsp; SWR is still lowest on ch 19 but was higher than before RF grounding.&nbsp; The physical length of the whip has not changed.&nbsp; The shunt coil &quot;what I called an inductor&quot; borrows capacitance from the ground plane (truck body) and gives it to the radiating element (whip) and bringing it back into balance, thus lowering the SWR.</blockquote>

[QUOTE="roadrage, post: 388319, member: 21185"] I am still learning this so forgive me if I am miss something. I am sure someone will correct me if I'm wrong. The way I understand it is: The physical length of the antenna is correct for 11 meters as the SWR curve is at its lowest on channel 19 of the CB band. When I began bonding the body of the truck (RF grounding) with ground strapping, it changed the size of the counterpoise. It is for the purpose of attempting to make the radiating pattern better and the antenna perform better on TX and RX. But changing the size of the ground plane causes a mismatch of sort. SWR is still lowest on ch 19 but was higher than before RF grounding. The physical length of the whip has not changed. The shunt coil "what I called an inductor" borrows capacitance from the ground plane (truck body) and gives it to the radiating element (whip) and bringing it back into balance, thus lowering the SWR. [/QUOTE]

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