Barry K3EUI
@K3EUIbarry
West Chester PA
Joined
Intro
I am a retired Physics teacher/professor having spent most of my adult life teaching high school (Westtown School, a coed Quaker boarding school near Philly) and college/university (Northern Arizona University, West Chester University, Bryn Mawr College).
My younger adult life was training as an Astronomer.
My intro began at Swarthmore College and Sproul Observatory (1967) where I learned about binary stars and parallax and astrometry. One of the fascinating topics was to learn about the orbital motion of the ‘barycenter of a double star’ (my first name is Barry). So that fascination became my Master’s Thesis: Orbital Motion of the Photocenter of a Binary Star about the Barycenter. It was fun and in less than one year, I changed the way mass ratios of nearby stars are determined via photographic astrometry. This was done with a 24 inch refractor (lens) telescope and 5 x 7 inch glass photographic plates - the OLD DAYS.
My next stint as a graduate student was at University of Arizona (Kitt Peak Observatory) in Tucson AZ where I learned from the best instructors in the world, but I changed my mind after one year of research and decided to try teaching high school science - my real passion. But during those early years I managed to work at Lowell Observatory and U.S.Naval Observatory in Flagstaff Arizona, and a summer at Greenwich Observatory in England.
For the next 41 years (1970-2011) and 41000 lab reports later I was a high school science teacher: physics/math/astronomy and some electronics and music. After retiring in 2011, I have spent more time relearning aspects of Ham Radio, including VNA technology.
Ham radio has always been a passion - ever since I was 12 yr old and got a Novice license: KN3EUI in 1958.
Antennas and Sound Card digital modes are still fascinating.
That’s about it.
de k3eui
My younger adult life was training as an Astronomer.
My intro began at Swarthmore College and Sproul Observatory (1967) where I learned about binary stars and parallax and astrometry. One of the fascinating topics was to learn about the orbital motion of the ‘barycenter of a double star’ (my first name is Barry). So that fascination became my Master’s Thesis: Orbital Motion of the Photocenter of a Binary Star about the Barycenter. It was fun and in less than one year, I changed the way mass ratios of nearby stars are determined via photographic astrometry. This was done with a 24 inch refractor (lens) telescope and 5 x 7 inch glass photographic plates - the OLD DAYS.
My next stint as a graduate student was at University of Arizona (Kitt Peak Observatory) in Tucson AZ where I learned from the best instructors in the world, but I changed my mind after one year of research and decided to try teaching high school science - my real passion. But during those early years I managed to work at Lowell Observatory and U.S.Naval Observatory in Flagstaff Arizona, and a summer at Greenwich Observatory in England.
For the next 41 years (1970-2011) and 41000 lab reports later I was a high school science teacher: physics/math/astronomy and some electronics and music. After retiring in 2011, I have spent more time relearning aspects of Ham Radio, including VNA technology.
Ham radio has always been a passion - ever since I was 12 yr old and got a Novice license: KN3EUI in 1958.
Antennas and Sound Card digital modes are still fascinating.
That’s about it.
de k3eui
Відхилити повідомлення
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Dipole antenna with Low Z0 feed point Impedance
All of the suggestions that have been mentioned will probably work to lower the SWR - but will it make any real difference in your radiation? Probably not. In short runs of decent coax, any loss that
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Barry K3EUI
· #38601
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Dipole antenna with Low Z0 feed point Impedance
I have a MUCH MUCH less messy solution. Is the dipole (center fed) 130 ft (80m) or 66 ft (40m) or 33 ft (20m)? Center feds will work on the 3rd harmonic, so a 40m can also tune to 15m. So…. try this …
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Barry K3EUI
· #38558
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down to two HF antennas
*Now down to two HF antennas at new QTH at Crosslands Retirement Community (Kennett Square) SW of Philly* * * *Still have major high noise level from 1-10 MHz and working to solve it. * * * *1) NVIS h
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Barry K3EUI
· #38520
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modified vertical for 17m band
I took a 1/2 wave vertical (17 ft tall) made from telescoping aluminum tubing and shortened it to 13 ft to try it on the 18.1 MHz (17m) band. Took out the impedance matching circuit and just hooked up
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Barry K3EUI
· #37844
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