Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising RF Cafe Forums Magazine USAF Radr Shop Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Thank you for visiting RF Cafe!
Triad RF Systems Amplifiers - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

AirplanesAndRockets.com

Innovative Power Products Couplers

Smooth Earth Diffraction Calc - RF Cafe Forums

RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2010, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts.

-- Amateur Radio

-- Anecdotes, Gripes, & Humor

-- Antennas

-- CAE, CAD, & Software

-- Circuits & Components

-- Employment & Interviews

-- Miscellany

-- Swap Shop

-- Systems

-- Test & Measurement

-- Webmaster

nubbage
 Post subject: Smooth Earth Diffraction Calc
Posted: Thu Jan 25, 2007 11:51 am 
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm

Posts: 304

Location: London UK

Hi Yorl

I have a trivial problem to solve but no budget for suitable software.

Anyone know a reliable freeware or website with a Java applet to compute smooth earth diffraction at VHF?

I am trying to predict performance of a system using yagi antennas at 160MHz over an 80km smooth path using -110 dBm sensitivity receivers and 45watts Tx power with 8 or 10dB gain antennas each end, low feeder loss.

"Anyone, anyone?"

And for 5 bonus points, where does that quote come from?

The usual undying devotion to those who can help.


 
   
 
Mr.Whatever
 Post subject:
Posted: Mon Mar 05, 2007 11:23 am 
 
Captain
User avatar

Joined: Fri Apr 07, 2006 6:10 pm

Posts: 22

I found this interesting article:

http://www.nor.com.au/community/sarc/re ... ateurs.pdf

I hope this helps. :-)


 
   
 
nubbage
 Post subject:
Posted: Tue Mar 06, 2007 6:01 am 
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm

Posts: 304

Location: London UK

Hi Whatever

Thanks a bunch for that link. As the author says "Information on the subject is very hard to come by."

I will follow up one of the references he mentions.

I had not seen this approach to analysis. It does not appear to be either ITU-R or NBS, and the author of the paper admits he has lost the provenance of the procedure.

Thanks again. It will give me a third approach, and hopefully narrow down the discrepancy I am experiencing when using different methods.


 
   
 
Mr.Whatever
 Post subject:
Posted: Wed Mar 07, 2007 5:22 pm 
 
Captain
User avatar

Joined: Fri Apr 07, 2006 6:10 pm

Posts: 22

Hi nubbage :)

If you send me an email at mr[dot]whatever[at]gmail[dot]com, I can try forwarding you a PDF file that I got. I'm not sure if it helps, but its worth a try.

Replace [dot] with . and [at] with @ in the email.


Posted  11/12/2012

Innovative Power Products Couplers
RF Cafe Sponsors
Exodus Advanced Communications Best in Class RF Amplifier SSPAs
Axiom Test Equipment - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free