I am a late bloomer in ham radio. I was not an engineer in a former
life, and am still grappling with basics.
I still find matters of IMPEDANCE ...SWR... reactance... radiation
resistance, etc., a puzzlement and a curiosity. Taking college
physics 35 years ago is not making it for me...
I am still "corn-fused" about the relationships between these concepts.
For example, my 43 foot stick had these different results before and
after I converted it to a 33 foot 40 meter ground plane.
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SWR @ 7.150 MHz @ 43 feet = 6.8 : 1 |Z|= 55 ohms
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SWR @ 7.150 MHz @ 32 feet = 1.40 : 1 |Z|= 38 ohms
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So... at 43 feet, I suppose I get a great impedance "match" at 55 ohms,
but at the expense of relatively high SWR... So I shorten it and get
a great SWR "match" at 1.40 : 1 SWR, but at the "expense" of dropping
impedance to 38 ohms (which is pretty much according to the text book.)
Do you guys know of a chapter in the ARRL Handbook or the ARRL ANTENNA
BOOK, or some other place where I can read up on how all these concepts
relate? Personally, I find it all very corn-fusing.
I am not complaining ... no mamby pamby whining going on in my shack...
;-)
I am just trying to understand what it all means ! So if you could
point me in the right direction, I will do my homework.
=================== JHR =========================
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