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Further to last month's RadCom article on what makes an antenna radiate ...

Gareth G4SDW (ne G8DXY) GQRP #3339
 

... I have discovered the following tutorial, and although I have not yet
worked through it, it does offer some interesting insights, including the
new (for me) approach of deriving Ohm's Law by consideration of
the electric field across a resistor.

These appear to be notes accompanying a lecture series but
at 2011 is nearly 50 years after my texts on the subject

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-013-electromagnetics-and-applications-spring-2009/readings/MIT6_013S09_notes.pdf

Dr. David Kirkby from Kirkby Microwave Ltd
 

On Tue, 17 Sep 2019 at 23:32, Gareth G4SDW (ne G8DXY) GQRP #3339 via Groups.Io <headstone255=yahoo.com@groups.io> wrote:
... I have discovered the following tutorial, and although I have not yet
worked through it, it does offer some interesting insights, including the
new (for me) approach of deriving Ohm's Law by consideration of
the electric field across a resistor.

These appear to be notes accompanying a lecture series but
at 2011 is nearly 50 years after my texts on the subject

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-013-electromagnetics-and-applications-spring-2009/readings/MIT6_013S09_notes.pdf

The maths is a bit heavy going.😀😀😀

After Peter Dodd died, there was a new antenna columnist. Was he the same person as now, or has there been another change?

Dave. 
--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...
https://www.kirkbymicrowave.co.uk/
Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales.
Company number 08914892.
Registered office:
Stokes Hall Lodge,
Burnham Rd,
Althorne,
Chelmsford,
Essex,
CM3 6DT,
United Kingdom

Neil Smith G4DBN
 

I rather like example 4.3B, analysing the screening effect of a Faraday shield in terms of the rise-time of magnetic field through a thin conductive shell.

Back in the 1970s at the Post Office College of Engineering Studies, I recall a derivation of Ohm’s law being done using the steady state of the field equations, which was taught most elegantly, with physical insights, by gifted lecturers. Certainly when contrasted with the rather pedestrian, clunky and hyper-mathematical approach at Uni and indeed even on the otherwise excellent Electromagnetism element of the OU Physics degree I did for fun a few years back while the grandchildren were doing their A levels and moaning about how Old People didn’t have the stress of exams and learning stuff.

Neil G4DBN

On 17 Sep 2019, at 23:32, Gareth G4SDW (ne G8DXY) GQRP #3339 via Groups.Io <headstone255=yahoo.com@groups.io> wrote:

... I have discovered the following tutorial, and although I have not yet
worked through it, it does offer some interesting insights, including the
new (for me) approach of deriving Ohm's Law by consideration of
the electric field across a resistor.

These appear to be notes accompanying a lecture series but
at 2011 is nearly 50 years after my texts on the subject

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-013-electromagnetics-and-applications-spring-2009/readings/MIT6_013S09_notes.pdf



Gareth G4SDW (ne G8DXY) GQRP #3339
 

On Tue, Sep 17, 2019 at 11:32 PM, Gareth G4SDW (ne G8DXY) GQRP #3339 wrote:


... I have discovered the following tutorial, and although I have not yet
worked through it, it does offer some interesting insights, including the
new (for me) approach of deriving Ohm's Law by consideration of
the electric field across a resistor.

These appear to be notes accompanying a lecture series but
at 2011 is nearly 50 years after my texts on the subject

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-013-electromagnetics-and-applications-spring-2009/readings/MIT6_013S09_notes.pdf
Continuing on with a flea in my ear about the subject, the following URL has some further animations embedded within ...

http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/coursenotes/modules/guide13.pdf