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Technical Topics => The RF Workbench => Topic started by: Charlie_Dont_Surf on January 16, 2023, 2007 UTC

Title: Transmission Line Transformers
Post by: Charlie_Dont_Surf on January 16, 2023, 2007 UTC

I mentioned over here that I was trying to find more information on designing transmission line transformers: https://www.hfunderground.com/board/index.php/topic,89881.msg335362.html#msg335362 (https://www.hfunderground.com/board/index.php/topic,89881.msg335362.html#msg335362)

I got what I was looking for and I figured that I would share:

The first reference is the second edition of a book that I own in print (first edition). Bowick, C., "RF Circuit Design". This section is basically untouched from the first edition: https://ia802603.us.archive.org/7/items/RFCircuitDesign2ndEdition/RF%20Circuit%20Design%20-%202nd%20Edition.pdf (https://ia802603.us.archive.org/7/items/RFCircuitDesign2ndEdition/RF%20Circuit%20Design%20-%202nd%20Edition.pdf) Starting on page 181 ("Broadband Transformers"), and especially pages 182-183, "Practical Winding Hints".

Also, Badger, G., “A new class of coaxial line transformers,” Ham Radio Mag azine, Part 1, 12–18, Feb. 1980, and Part 2, 18–29, Mar. 1980.

Title: Re: Transmission Line Transformers
Post by: ~SIGINT~ on January 17, 2023, 0032 UTC

Thank you for sharing. This is a nice book.

I have a hard copy of the ARRL Transmission Line Transformers 2nd Ed by Jerry Sevick, W2FMI which I picked up at a surplus store and is also a good resource.

Title: Re: Transmission Line Transformers
Post by: Charlie_Dont_Surf on January 21, 2023, 2126 UTC

Quote from: ~SIGINT~ on January 17, 2023, 0032 UTC

Thank you for sharing. This is a nice book.

I have a hard copy of the ARRL Transmission Line Transformers 2nd Ed by Jerry Sevick, W2FMI which I picked up at a surplus store and is also a good resource.

I have not seen the ARRL book you mention.

Sevick died in 2009 and was a bright man but I'm not a huge fan of his cookbook style books like:

https://www.amidoncorp.com/understanding-building-and-using-baluns/ (https://www.amidoncorp.com/understanding-building-and-using-baluns/)
https://www.amidoncorp.com/transmission-line-transformer-handbook/ (https://www.amidoncorp.com/transmission-line-transformer-handbook/)

Without question there is a place for cookbooks but the organization of the text leaves me wanting and the photos of the finished products are 1970's style-low-contrast B&W gems that do nothing for me.

 The last of the big reference books that he made before he passed away was the 4th edition, which looks better:
https://www.okdxf.eu/files/Noble%20Publishing%20-%202001%20-%20Transmission%20Line%20Transformers,%204ed.pdf (https://www.okdxf.eu/files/Noble%20Publishing%20-%202001%20-%20Transmission%20Line%20Transformers,%204ed.pdf)

After he passed away, Raymond Mack took up the task of reorganizing and refreshing the information into the 5th edition. I have not read it but on a quick scan the text looks a bit better to me and the photos are up to modern standards:
https://pdfroom.com/books/sevicks-transmission-line-transformers-theory-and-practice/qjb5q6EMdxQ (https://pdfroom.com/books/sevicks-transmission-line-transformers-theory-and-practice/qjb5q6EMdxQ)