length is same or different

[citizen]

hi everyone!!!!
i have this doubt that
is the length of the all resonator is same?
i saw in IEEE paper that end resonator is some 0.02-0.05 inches longer than the intermediate elements (not coupled filter case for tapping case of interdigital and combline filter only im asking this)

any one clarify this plz!!!!!!!!

thgank you

 

[grandizer]

Yes , it used like that in order to compensate for frequency shift..
after you use the tapped coaxial input it could be the frequency will shift a little bit and in order to compensate you change the resonator lenght..

 

[RF-OM]

Edge resonators usually require capacitive termination when tapped. This is because taps brings some inductance. Capacitive termination can be done by placing small wider elements at the ends of resonators or, sometimes, by resonator elongation. This is normal.

Why you jump to another topic, by the way?

Best regards,
RF-OM

 

[citizen]

RF-OM wrote:

Why you jump to another topic, by the way?

i didnt get this these are my small doubts in practical way which i have seen , but dont know the reasons .
thats y i post those doubts here and clarify
thank you

 

[RF-OM]

I understood it, thank you. I thought I offended you somewhat and you change the topic, but now I am glad that this is not the case.

Best regards,
RF-OM

 

[citizen]

thank you
can you suggest me a good book for the basic things that your telling so that i can design more practical working combline or interdigital filters,
thank you

 

[RF-OM]

I do not know where you are in filter design. For beginners definitely Randal Rhea books "HF filter design and computer simulation" is very good. His filter design modules embedded into Genesys program are the best filter design programs. They allow to get design done quick and the accuracy is good. For example small (5x6mm size) 9th order interdigital band-pass filter for 4 GHz band was designed for less than an hour with all EM simulations. Lab test result was practically identical to simulation with 1.5% accuracy. This is really good software. Beside Rhea's book there are a lot of good books. From the old handbooks I personally prefer Hansel. For engineers it is better than Zverev. I can check my library and find the titles and other information if you need.

Best regards,
RF-OM

 

[citizen]

yes i know the book and soft ware also , i successed in those also now i prepared good microstrip working modules but
i want to design cavity combline filter with round rods so thst i have more rejections in stop band ,
for this only im searching i have designed filters with round rod but the book needed for me to design the practically good filter to meet my spec for that , i have to be have stuff of the basics thats y im asking any book for this concept learning
thank you

Added after 5 hours 33 minutes:

RF-OM wrote:

This is really good software. Beside Rhea's book there are a lot of good books. From the old handbooks I personally prefer Hansel. For engineers it is better than Zverev. I can check my library and find the titles and other information if you need.

can you give me the titles and other information of those books u told here

thank you

 

[RF-OM]

I checked some book and it is not easy to find an information about your filters. Here are some good books about filter design. May be not all have chapters about your filters, but at least they are worth to see.

1. Microwave Filters, Impedance Matching network and Coupling Structure.Matthaei.Artech House.1980.


2. Microwave Resonators and Filters For Wireless Communication.Makimoto & Yamashita. Springer.2001.

3. Microwave Resonators and Filters For Wireless Communication. Thede. Artech House. 2004.

4. Microwave Filters for Communication Systems: Fundamentals, Design, and Applications. Cameron, Kudsia, Mansour. Wiley-Interscience. 2007.

5. Filter Design and Evaluation. Hansel. Van Nostrand Reinolds Company. New York. 1969.

You may also check web for good filter design software and MathCAD/Matlab sites. I found some good design files there in the past.

Best regards,
RF-OM

 

[citizen]

thank you for u r information ,
do you have the books

->Microwave Filters for Communication Systems: Fundamentals, Design, and Applications. Cameron, Kudsia, Mansour. Wiley-Interscience. 2007

->Filter Design and Evaluation. Hansel. Van Nostrand Reinolds Company. New York. 1969

if u have, can u post them plz...... if possible ........
thank you

 

[RF-OM]

I have these book only as hard copies. It will be nice to have them as soft copies too. If you find them please let me know.

Best regards,

RF-OM

 

[citizen]

i have the first(mattaei) and second(Yamashita) books as soft copies(i think scanned version only) with me that to from this board only i downloaded them , search them , other wise i will post them,if u want .............

best regards
citizen

 

[RF-OM]

Thank you! If these books are good copies It will be nice to have them. If copies are not good I probably will not be able to read (in my age it is hard to read from screen and if copy is not good it is a nightmare). I usually use soft copy to search and find what I need, then note the page number and read it from the hard copy.

By the way, today I try to send to you one paper about cavity filters but edaboard site did not allow me to send. I try to do it again now. Does not work. I do not know what is going on.

Thanks again,
RF-OM

 

[citizen]

this is the link in this board t o get the second book,in your list and the mattaei book is also with and also here in this board also but scanned version but you try for that, here it is


for mattaei book i also have a scanned version and it is good for u also no problem with u rs sight i think , but try once the link above if it is not good i will post that book here ,
can you send me the cavity filter paper tomy mail id,
hai_maha@yahoo.com
thank you

 

[RF-OM]

Thanks a lot! I will try these link on July 1st because I already exceed my June download limit.

Best regards,
RF-OM

 

[citizen]

By the way, today I try to send to you one paper about cavity filters but edaboard site did not allow me to send. I try to do it again now. Does not work. I do not know what is going on.

Thanks again,
RF-OM

can you send that cavity filter paper to my mail id, may it will be useful to me:
id:hai_maha@yahoo.com

thank you

 

[RF-OM]

To citizen,

Finally I found why this paper did not go through. The file size was 24MB! I reduce it to 1.5 MB and sent to your e-mail address. Please check it.

Best regards,
RF-OM

 

[citizen]

thank you
i will check it out you told that , that paper was of 24MB but i reduce it to 1.5 MB, means any thing reduced or make it as rar file , ok letme see first ,

y am asking this means im not getting any information from net or any other source also for these filters thats y i dont want to miss any information regarding this ,thank you once again

 

[RF-OM]

I checked it before sending to you. It looks absolutely the same as 24MB version. I cannot understand why there is so big difference in file size and why initial file was so big. It is kind of black magic. By the way, this is recent paper and you can go to Microwave Journal site and check it. If it is something really interesting of course.