Menu

Current across the antenna loading coil - from scratch

Search this Thread

Prev

Previous Post

Next Post

Next

#10

Report Post

Old

April 11th 06, 02:08 AM posted to rec.radio.amateur.antenna

Cecil Moore

Posts: n/a

Default

Current across the antenna loading coil - from scratch

Cecil Moore wrote:

wrote:

Radiation does not cause current taper. Dissipation does not either.

Radiation and dissipation are considered to be losses in a
transmission line covered by the attenuation factor. All that
is needed to prove your above assertions to be false is to
quote a transmission line equation. It can even be the more
simple flat form where the SWR is 1:1. Here it is in ASCII:

I = Im*e^(ax)*e^j(wt-bx)

Note this is the equation for *CURRENT* where 'a' is the attenuation
factor. The attenuation factor includes radiation and dissipation.

Your statements indicate a high level of ignorance. Assuming a flat
transmission line with an SWR of 1:1, if the loss in the transmission
line is 3 dB, we can put 200 watts into 50 ohm coax at the source end
and get 100 watts out at the 50 ohm load end. The current out of the
source is SQRT(200w/50) = 2 amps. The current through the 50 ohm load
is SQRT(200w/50) = 1.414 amps. The current has dropped from the source
^^^
Obviously, should be 100w. Sorry for the typo.

to the load by exactly the same percentage that the voltage has dropped.

What you seem to be missing is that the H-field is attenuated by the
same amount as the E-field while the ratio of E-field to H-field
remains constant and equal to Z0. Current is proportional to the
H-field and voltage is proportional to the E-field.
--
73, Cecil http://www.qsl.net/w5dxp

Reply With Quote

Reply With Quote

Thread Tools	Search this Thread
Show Printable Version	Search this Thread: Advanced Search
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode

Posting Rules
Smilies are On [IMG] code is On HTML code is Off Trackbacks are On Pingbacks are On Refbacks are On

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Imax ground plane question	Vinnie S.	CB	151	April 15th 05 05:21 AM
Questions -?- Considering a 'small' Shortwave Listener's (SWLs) Antenna	RHF	Shortwave	1	January 24th 05 09:37 PM
FS: sma-to-bnc custom fit rubber covered antenna adapter	Stephen G. Gulyas	Scanner	17	December 7th 04 06:42 PM
FS: sma-to-bnc custom fit rubber covered antenna adapter	Stephen G. Gulyas	Swap	17	December 7th 04 06:42 PM
Current in loading coil, EZNEC - helix	Yuri Blanarovich	Antenna	334	November 9th 04 05:45 PM

All times are GMT +1. The time now is 05:34 PM.

About Us

"It's about Radio"

Contact Us RadioBanter forum home Privacy Statement

Copyright © 2017