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Since you are probably ending up with 1 W or less at the other end, the power rating of the resistors should be 1/16 W or so. ordinary surface mount types will do. Double check the data sheets to make sure of the frequency rating. If this network is to be operated at higher power levels, special power resistors, such as made by Anarin http://www.anaren.com/docs/app_notes/AAN-1004 - SMD RES.pdf should be used.
anyway, for squared coaxial lines I found equations about characteristic impedance; at the moment for rectangular lines into squared lines I've no formulas.... So, I've thought to use some 3D e.m. software to evaluate the characteristic impedance everytime I change the horizontal (or vertical) dimension of the inner conductor...
Do you think it's a possible method? In this way the results depend on the mesh I'm using and on the accuracy of the code.. So they don't derive from a rigorous analysis like in squared coaxial line.
What do you think?
I think it's not the same thing: for a stripline structure for most of e.m.
codes you have formulas to estimate guided lambda, characteristic impedance (given the line width), line width (given the line impedance).
As an example, Ensemble offers this option... Of course you can't consider discontinuity effects but it's a good starting point.
In my case, the rectangular coaxial line is a too particular configuration; in fact I can't find in litterature formulas for the associated line impedance... So I'm obliged to build a configuration by a 3D code, mesh it very carefully, run the simulation and to hope the result to be accurated...
If I consider more lines with different rectangular sections, I can have strong discrepancies between simulated and measured components...
Hope you find some article or formula about configurations of rectangular inner conductors into squared outer conductors.
I've scanned 4 pages which maybe they are useful for you. I'm afraid the scanned pages give a quite huge archive (which will be uniquely useful for you, and even this it is not sure). do i upload the file (8Mb) or send to you as pm?
As you like Dowjones.. I don't know how many Elektroda people work with rectangular section lines coaxial to squared section lines....
Probably just a few... If you want you can send the material to my e-mail or as a private message...For me it doesn't matter.
What type of formulas did you find? Line Impedance, Losses?
Thanks a lot... you know my interests, you can just ask if you have a question.
they are only 4 scanned pages. the first page is from antenna handbook (by Lo & Lee) the other pages are from Microwave Engineers Handbook (by Hansen and Wheeler 1971 Artech House). I keep the size so that the figures can be read.