Some recent posts on grounding reminded me of something I've always wondered about. How is the radiation efficiency of a copper wire HF antenna affected by oxidation of the copper over time? Empirica
I'm not sure what the effect on radiation efficiency could be, but I can think of a possible way to see if it has any effect at all. 1. Put up a 20m dipole comprised of shiny new wire. Measure it's
That being said, the loss would probably have to be significant for it to show up as a perceivable difference in radiated RF, especially if you were to assume that you could match any difference in i
Rudy N6LF researched a number of issues that relate to these questions = http://rudys.typepad.com/files/insulated-wire-and-antennas.pdf Andrew published some research that shows the PIM (passive inte
On 4/24/18 12:05 PM, Shawn Donley wrote: Some recent posts on grounding reminded me of something I've always wondered about. How is the radiation efficiency of a copper wire HF antenna affected by ox
Andrew published some research that shows the PIM (passive intermod) differences between braid and solid copper shields for coax. I couldn't find that pdf on the web, but it shows how braid generate
On 4/24/2018 2:45 PM, Steve Maki wrote: Mostly true. For HF it's insignificant. For UHF and above it's insignificant for receive only or simplex. For UHF duplex (repeaters) I *think* it can be signif
Mostly true. For HF it's insignificant. For UHF and above it's insignificant for receive only or simplex. For UHF duplex (repeaters) I *think* it can be significant. LMR style cables have very poor P
Interesting data. One reference I found discussed the dramatic increase in PIM from motion induced rubbing of coax braid strands, although again unlikely an issue at HF. Thus one might suppose a bare
Mostly true. For HF it's insignificant. For UHF and above it's insignificant for receive only or simplex. For UHF duplex (repeaters) I *think* it can be significant. LMR style cables have very poor P
On 4/24/2018 2:43 PM, jimlux wrote: On 4/24/18 12:05 PM, Shawn Donley wrote: Some recent posts on grounding reminded me of something I've always wondered about. How is the radiation efficiency of a
On 4/25/18 8:16 PM, Michael Tope wrote: On 4/24/2018 2:43 PM, jimlux wrote: On 4/24/18 12:05 PM, Shawn Donley wrote: Some recent posts on grounding reminded me of something I've always wondered about
On 4/24/2018 2:43 PM, jimlux wrote: On 4/24/18 12:05 PM, Shawn Donley wrote: Some recent posts on grounding reminded me of something I've always wondered about. How is the radiation efficiency of a