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gamma match
- Thread starter 2112
- Start date
i see
Doc what i meant was out to the side-meaning the way the book says put them and inline being you can look strait down the elements and not see the gamma match.That being the best way that i can describe the question.Do you see what i'm talkin about? Which would be better,but like you said, probly by the book.
Thanks
Doc what i meant was out to the side-meaning the way the book says put them and inline being you can look strait down the elements and not see the gamma match.That being the best way that i can describe the question.Do you see what i'm talkin about? Which would be better,but like you said, probly by the book.
Thanks
I read it as above or below the element versus in front of or behind it for a horizontal element.Do it like the manual says.
MC, did you figure it out yet? Does it sound like some far fetched CB story that 2112 heard about his antenna and how to make it work better?
I read it to mean in front of or in back of the element, 90 degrees from what the instructions suggest.
I read it to mean in front of or in back of the element, 90 degrees from what the instructions suggest.
Okay, I think I see where you're comming from (or going?). Personally, I don't think it would make enough difference to make any difference. But, the people who made the thing should know what they're talking about, so do it their way. Which is the 'right' way? I ain't telling! (mainly cuz I don't know.)
- 'Doc
- 'Doc
I would ask 2112 that question! He is the one that brought it up. Would you suspect that 2112 may feel there is some advantage using this idea he suggests?
If 2112 had suggested that having the gamma on the bottom of the horizontal element was best or making the vertical gamma pointing down was best, I might agree that such could be an advantage.
If 2112 had suggested that having the gamma on the bottom of the horizontal element was best or making the vertical gamma pointing down was best, I might agree that such could be an advantage.
One last thought on the subject.
Since part of the work that a gamma match does is introduce inductance and capacitance to change the input impedance, and since the inductance and capacitance of the antenna in relation to the earth also affects it's input impedance (and point of resonance), positioning the gamma horizontally to earth will increase that the antenna's interaction with the earth (ground) to some extent (also assuming that the antenna is horizontal to ground to start with). The areas of 'exposure' being equivalent to the area of the plates of a capacitor determining it's total capacitance. If part of the gamma was 'hidden' from ground that interaction would be reduced. (You see where I'm going with this?) So, the placement of the gamma ~could~ make some difference in the efficiency of the antenna due to it's interactive reactance with earth/ground!
- 'Doc
PS - Now, having said all that, the placement of the gamma will make absolutely NO practical difference in the 'real world' with the typical antenna at anything close to 'normal' operating conditions. The only 'areas' of the gamma that I can think of off hand that would make any difference would be the area of the connecting strap on the outer end of the gamma. What's that, something like 1" x 3", or 3 square inches of 'plate' area? A capacitor's plates of 3 sq.inches, with a distance between plates of anything over just a few inches just doesn't make for much capacitance... more like an open circuit, right? Well, maybe at SHF or EHF, sort of. Naaw, forget it, not even at 'light' frequencies... Wait a minute! If the velocity factor of the material used to make the gamma match could be such that the VF was a double digit whole number, it would mean faster than light propagation! OMG! That would mean that antennas for cell phones would have to be several yards long just to account for the gamma match! No wonder those stinking little antennas make the cellphone loose signal every now and then. I am a genius!
(and this is so much B.S. that the Sahara would turn green over night)
Since part of the work that a gamma match does is introduce inductance and capacitance to change the input impedance, and since the inductance and capacitance of the antenna in relation to the earth also affects it's input impedance (and point of resonance), positioning the gamma horizontally to earth will increase that the antenna's interaction with the earth (ground) to some extent (also assuming that the antenna is horizontal to ground to start with). The areas of 'exposure' being equivalent to the area of the plates of a capacitor determining it's total capacitance. If part of the gamma was 'hidden' from ground that interaction would be reduced. (You see where I'm going with this?) So, the placement of the gamma ~could~ make some difference in the efficiency of the antenna due to it's interactive reactance with earth/ground!
- 'Doc
PS - Now, having said all that, the placement of the gamma will make absolutely NO practical difference in the 'real world' with the typical antenna at anything close to 'normal' operating conditions. The only 'areas' of the gamma that I can think of off hand that would make any difference would be the area of the connecting strap on the outer end of the gamma. What's that, something like 1" x 3", or 3 square inches of 'plate' area? A capacitor's plates of 3 sq.inches, with a distance between plates of anything over just a few inches just doesn't make for much capacitance... more like an open circuit, right? Well, maybe at SHF or EHF, sort of. Naaw, forget it, not even at 'light' frequencies... Wait a minute! If the velocity factor of the material used to make the gamma match could be such that the VF was a double digit whole number, it would mean faster than light propagation! OMG! That would mean that antennas for cell phones would have to be several yards long just to account for the gamma match! No wonder those stinking little antennas make the cellphone loose signal every now and then. I am a genius!
(and this is so much B.S. that the Sahara would turn green over night)